ICES WGFTFB REPORT 2008
ICES FISHERIES TECHNOLOGY COMMITTEE
ICESCM 2008/FTC:02
REF. WGECO
Report of the ICES-FAO Working Group on Fish
Technology and Fish Behaviour (WGFTFB)
21-25 April 2008
Tórshavn, Faroe Islands

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Recommended format for purposes of citation:
ICES. 2008. Report of the ICESFAO Working Group on Fish Technology and Fish
Behaviour (WGFTFB), 2125 April 2008, Tórshavn, Faroe Islands. ICES CM
2008/FTC:02. 265 pp.
For permission to reproduce material from this publication, please apply to the Gen
eral Secretary.
The document is a report of an Expert Group under the auspices of the International
Council for the Exploration of the Sea and does not necessarily represent the views of
the Council.
© 2008 International Council for the Exploration of the Sea

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ICES WGFTFB REPORT 2008
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Contents
Executive summary ................................................................................................................1
1
Directive ..........................................................................................................................4
2
Introduction ....................................................................................................................4
2.1 Terms of Reference ...............................................................................................4
2.2 Participants ............................................................................................................6
2.3 Explanatory note on meeting and report structure..........................................6
3
WGFTFB advice and requests during 2007­2008 .....................................................6
3.1.1 WGEF Request on Outrigger Trawls ....................................................7
3.1.2 EU request on Baltic Cod Selectivity.....................................................9
3.1.3 Request from WGSSDS on selection patterns ....................................12
3.2 Request from ACE on the use of VMS data ....................................................15
3.3 Meeting of WGFTFB Chair with EU Commission and Net
manufacturers on technical measures regulations.........................................15
3.4 SGMIXMAN ........................................................................................................17
3.5 AMAWGC ...........................................................................................................17
3.6 SGBYC ..................................................................................................................18
4
ICES draft science plan 2007­2013............................................................................18
5
Report from Study Group on the Development of Fish Pots for
Commercial Fisheries and Survey Purposes (SGPOT).........................................18
6
Report from Working Group on Quantifying All Fishing Mortality
(WGQAF) ......................................................................................................................19
7
FAO request for clarification on Bycatch terminology.........................................20
8
Update on Gear Classification Topic .......................................................................21
9
WWF Smart Gear Competition .................................................................................22
10 ToR a): Species Separation in demersal trawls ......................................................22
10.1 General Overview...............................................................................................22
10.2 Terms of Reference .............................................................................................23
10.3 List of Participants ..............................................................................................23
10.4 Actions .................................................................................................................24
10.5 Timetable for completion of work....................................................................24
10.6 Recommendations ..............................................................................................24
10.6.1 Summary of Haddock Symposium 2007 as it relates to
species separation ..................................................................................25
10.6.2 Can Yellowtail Flounder be harvested without bycatch of
cod and haddock on Georges Bank? Realtime spatial
temporal fishing strategies ...................................................................25

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ICES WGFTFB REPORT 2008
10.6.3 UK trials with the eliminator trawl and a new simple
method for catch comparison analysis................................................26
11 ToR b): Advice to Assessment WG's........................................................................26
11.1 General Overview...............................................................................................26
11.1.1 Terms of Reference ................................................................................27
11.1.2 General Issues.........................................................................................27
11.1.3 Information for Individual Assessment Working Groups...............31
11.1.4 Recommendations .................................................................................31
12 ToR c): Static Gear Selectivity Manual ....................................................................31
12.1 General Overview...............................................................................................31
12.1.1 Terms of Reference ................................................................................31
12.1.2 General Issues.........................................................................................32
12.1.3 List of Participants .................................................................................33
12.1.4 Recommendations .................................................................................33
12.2 Individual Presentation .....................................................................................33
12.2.1 Size selectivity of basket traps for the gastropod Nassarius
mutabilis in the Adriatic Sea..................................................................33
13 ToR (d) Mitigation Technologies for Protected Species.......................................35
13.1 General Overview...............................................................................................35
13.1.1 Terms of Reference ................................................................................35
13.1.2 Identification of technical mitigation measures.................................35
13.1.3 Assessment of efficacy of the technical measures .............................36
13.1.4 List of Participants .................................................................................37
13.1.5 Conclusions ............................................................................................37
13.1.6 Recommendations .................................................................................37
13.2 Individual Presentations....................................................................................38
13.2.1 Turtle Excluder Devices Experiments in the Central
Adriatic Sea.............................................................................................38
14 ToR e): Request form WGEF......................................................................................39
15 ToR f): Ad hoc Topic Group on Shrimp Trawl Efficiency ...................................39
15.1 Request.................................................................................................................39
15.2 Shrimp Trawl Evolution ....................................................................................40
15.3 General Comments .............................................................................................41
15.4 Icelandic Effort Data...........................................................................................41
15.5 Catch Quality versus Catch Rate ......................................................................43
15.6 List of Participants ..............................................................................................44
15.7 Conclusions .........................................................................................................44
15.8 Recommendations ..............................................................................................44
16 ToR g): WGECO request as part of the OSPAR QSR 2010 ..................................45
16.1 General Overview...............................................................................................45

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ICES WGFTFB REPORT 2008
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16.1.1 Terms of Reference ................................................................................45
16.1.2 General Issues.........................................................................................46
16.1.3 Conclusions ............................................................................................47
16.1.4 Recommendations .................................................................................48
17 FAO Reduction of Bycatch in Tropical Shrimp Trawling (REBYC)
project ............................................................................................................................49
17.1 Overview..............................................................................................................49
17.2 National Report Summaries..............................................................................49
17.2.1 Philippines ..............................................................................................49
17.2.2 Southeast Asia ........................................................................................50
17.2.3 Indonesia.................................................................................................51
17.2.4 Iran...........................................................................................................51
17.2.5 Bahrain ....................................................................................................52
17.2.6 Cuba.........................................................................................................52
17.2.7 Trinidad and Tobago.............................................................................53
17.2.8 Venezula..................................................................................................53
17.2.9 Mexico .....................................................................................................54
17.2.10
Columbia ..........................................................................................54
17.2.11
Costa Rica .........................................................................................55
17.2.12
Nigeria ..............................................................................................56
17.2.13
Cameroon .........................................................................................56
17.3 List of Participants ..............................................................................................57
17.4 Conclusions .........................................................................................................57
18 Summary of Other Presentations..............................................................................58
18.1 Nordic Project; Research in big mesh pelagic trawls.....................................58
18.2 Direct observations of large mesh capelin trawls; evaluation of
mesh escapement and gear efficiency..............................................................58
18.3 Design and test of a topless shrimp trawl to reduce pelagic fish
bycatch in the Gulf of Maine pink shrimp fishery .........................................59
18.4 FISHSELECT a tool for predicting basic selective properties for
netting ..................................................................................................................60
18.5 Technical and selective properties of T90 meshes codendextension
tandems made of different netting stiffness....................................................61
18.6 Fuel Saving Initiatives in the French Fishing Industry..................................61
18.7 Modelling flow through and around nets using computational
fluid dynamics ....................................................................................................62
18.8 Comparison of selective properties for nettings when used in
normal direction versus in 90 degrees turned direction (Poster).................62
18.9 Simulationbased study of precision and accuracy for methods to
assess size selective properties of codends (Poster).......................................63
19 National Reports ..........................................................................................................65
19.1 Belgium ................................................................................................................65
19.2 Canada .................................................................................................................67

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ICES WGFTFB REPORT 2008
19.3 Denmark ..............................................................................................................69
19.4 Faroe Islands........................................................................................................69
19.5 France ..................................................................................................................71
19.6 Germany ..............................................................................................................74
19.7 Iceland ..................................................................................................................79
19.8 Ireland ..................................................................................................................81
19.9 Netherlands .........................................................................................................84
19.10 Norway ................................................................................................................86
19.11 Spain ..................................................................................................................90
19.12 Scotland................................................................................................................94
19.13 USA
..................................................................................................................99
20 New Business .............................................................................................................108
20.1 Date and Venue for 2009 WGFTFB Meeting.................................................108
20.2 Proposals for 2009/2010 ASC ­ Theme Sessions ...........................................108
20.3 ICES and other Symposia ................................................................................109
20.4 Any Other Business ..........................................................................................109
Annex 1: List of participants.............................................................................................110
Annex 2: Agenda.................................................................................................................115
Annex 3: Recommendations .............................................................................................117
Annex 4: WGFTFB terms of reference for the next meeting.......................................119
Annex 5: Study Groups .....................................................................................................124
Annex 6: Proposed Term of Reference JFTAB ..............................................................126
Annex 7: Outline of CRR Report on Species Separation ............................................128
Annex 8: WGFTFB Information for other ICES Expert Groups ­
Questionnaire sent to WGFTFB members ............................................................131
Annex 9: Compendium of Mitigation Technologies ...................................................160
Annex 10: Loggerhead Turtle (Caretta caretta) bycatch, case study:
Mediterranean Sea.....................................................................................................171
Annex 11: WGECO request as part of the OSPAR QSR 2010 ....................................180
Annex 12: Reports from National Coordinators of the FAO Project
(REBYC 1) ....................................................................................................................201

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ICES WGFTFB REPORT 2008
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Executive summary
The ICESFAO Working Group on Fish Technology and Fish Behaviour (WGFTFB)
met in Tórshavn, Faroe Islands from 21­25 April 2008 to address seven Terms of Ref
erence. The main outcomes related to the ToRs are detailed below.
Key Findings
Species separation in demersal trawls (Section 10)
· A summary of the status of knowledge and future directions in research
and application on the behaviour and species separation in commercial
species would greatly benefit FTFB members and the fishing industry. A
WGFTFB topic group will continue to concentrate on behaviour and spe
cies separation of commercial demersal species in bottom trawls.
· WGFTFB therefore recommends the publication of an ICES Cooperative
Research Report on Species Separation based on the work carried out by
the Topic Group. A timetable and structure for this CRR report have been
agreed.
Advice to Assessment Working Groups (Section11)
· The overall picture from the questionnaires in 2008 is quite negative. Due
to a combination of soaring fuel prices, reduced quotas, decreasing fishing
opportunities and volatile prices for several key species notably nephrops,
haddock, cod, monkfish and hake, there is a general air of despondency in
the fleets across Europe.
· There seems to be a general trend of effort reduction across fleets and also
widespread evidence of fishermen in many countries reverting to more
fuel efficient methods in an attempt to reduce operating costs and maintain
economic viability.
· The effects of technological creep are still evident in many fisheries but the
concept of negative creep reported in 2006 and 2007 is now becoming more
prevalent as vessels try to reduce operating costs to counteract high fuel
prices. Most technological creep observed has concentrated on reducing
the drag of fishing gear.
· In a number of fisheries, there is some evidence of voluntary uptake of
gear mitigation measures. The drivers for uptake are either regulatory i.e.
as a means of achieving increased fishing opportunities or economic
through improved fish quality. There has also been evidence of some ves
sels adopting more selective gear as a way of improving public perception.
· Evidence of discarding has been observed in a number of fisheries
2007/2008. The motivations for discarding are a mixture of regulatory or
economically driven. Specific examples include cod in Area VIIbk and in
the Baltic Sea.
· Ghost fishing in the deepwater fisheries in Areas IV, VI and VII remains a
problem. There are reports of discarded longlines and gill nets along the
Scottish west coast deep water grounds and in the northern North Sea and
predation of fish catches by Grey seals from gillnet/tangle net fisheries has
become an increasing problem on the south coast of Ireland.

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ICES WGFTFB REPORT 2008
· As has become the trend in recent years there are very few reports of new
fisheries being developed but a few specific examples are reported such as
sea cucumber in Iceland and squid in the Moray Firth and at Rockall.
Gillnet Selectivity Manual (Section 12)
· The original ICES draft static gear selectivity manual was felt to be 80%
complete and on the basis of the information available it was agreed that it
was a worthwhile exercise to complete the manual. It was felt pertinent to
restrict the manual to static nets only i.e. gillnets, trammel nets and tangle
nets.
· A timetable for completion of the manual was agreed with a completion
date of mid2009. Subject to technical review, the manual will be consid
ered as a joint ICES/FAO publication. No financial commitment has been
made at this stage.
Mitigation Measures for Protected Species (Section 13)
· WGFTFB acknowledges the work carried out by ICES SGBYC in develop
ing the table of mitigation measures and has sought to update this table.
· WGFTFB concludes that the impact of fisheries on Loggerhead turtle needs
to be considered urgently given the scale of the problem. Research into the
applicability of proven mitigation technologies to reduce the bycatch
should be supported.
· WGFTFB has been unable to use the methodology developed in 2008 to as
sess the efficacy of mitigation measures for protected species. WGFTFB
conclude that this methodology is data dependent and for most protected
species with bycatch issues such data does not exist currently.
Advice to WGEF on outrigger trawls (Section14)
· WGFTFB concluded that Belgian and UK trials suggest the use of outrigger
trawls may lead to an increase in the catch of rays, particularly when ves
sels specifically target this species. Some technical limitations with this
gear for larger vessels relating to gear spread have been highlighted. In
practice this means, at least in the short term, that the uptake for this gear
will be limited to smaller vessels in Belgium and the impact on ray stocks
maybe not that significant although this needs monitoring. This may not
necessarily be the case in the UK, where indications are that large beam
trawl vessels may adopt this gear, due to fuel costs.
Advice to NIPAG & STACREC on shrimp trawl efficiency (Section15)
· WGFTFB concludes that due to the catching process for shrimp, horizontal
opening is more important than filtered volume with respect to catch vol
umes and this is reflected in the current trends in shrimp trawl design.
· WGFTFB concludes that due to the fundamental differences in the catching
process, comparisons between single and twin trawls for fish species and
shrimp are not relevant. This is because herding efficiency by sweeps can
very much influence capture efficiency for fish but not for shrimp.
· WGFTFB can find no reliable estimates of single vs. twin trawl efficiency
based on horizontal spread. Icelandic effort data using trawl circumference
shows average catch rates for twin trawls of between 1.25­2.24 times that
of a single trawl, with an average of 1.66.

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ICES WGFTFB REPORT 2008
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· WGFTFB can find no evidence of multiple rigs being used to improve
catch quality. The main tool used that does improve catch quality is the
Nordmore sorting grid. There is evidence, however, of fishermen using
twin or trouser codends to reduce the risk of gear damage, increase win
gend spread and improve catch quality.
WGECO request as part of the OSPAR QSR 2010 (Section 16)
· The integration of fishing gear technology research in the framework for
fisheries management is a prerequisite for achieving an ecosystembased
approach. It is recommended that many of the issues evolving from the se
lected case studies outlined by WGFTFB should be taken into account in a
framework for assessing impacts and management measures related to
fishing gear based technical measures.
· The efficacy of gear based technical measures is currently infrequently as
sessed. In this respect WGFTFB conclude that the protocol used in the UK
study to evaluate the legislation put into force for the C. crangon fisheries is
both holistic and effective. The same protocol can potentially be used else
where in other fisheries to conduct similar evaluations on the efficacy of
gear based technical measures.
· While focus on a more ecosystembased approach is emerging gradually,
little fishing gear research is directed towards other ecosystem compo
nents. Therefore there is need to consider biological and ecological impacts
of gear configurations and modifications during the research phase and be
fore inception into legislation.
· Research on gear modifications to improve selectivity of commercial fish
species through a variety of sorting devices has been proven to reduce by
catch and discards rates, mainly of fish species (Valdemarsen and Suu
ronen, 2003, Suuronen and Sarda, 2008). The application of these gear
modifications can be achieved through regulations or sometimes through
voluntary use by fishermen. Regulatory and market incentives can both
lead to an improvement of fishing practice.
· From the case studies, it can be seen that communication and education are
vitally important when introducing gear based measure into legislation.
Regulations are sometimes introduced quickly, but it takes time for the
fishing industry to adapt.
· When framing legislation, there is a need to consider all relevant issues
(e.g. practicalities, socioeconomic and technical aspects, etc.) to ensure that
gear measures, proven effective in fishing gear research, meet their objec
tives after implementation.
· Nonregulatory uptake of technical gear measures can be achieved
through various incentives. These incentives can be marketdriven, but in
dustry may also be motivated by uptake which has the potential to im
prove the public perception of fishing.
FAO Reduction of Environmental Impact from Tropical Shrimp Trawling (REBYC 1)
· In 2008, REBYC I will come to an end. Significant progress has been made
towards reducing the bycatch of large charismatic species such as marine
turtles captured by tropical shrimp trawls, however, significant problems
remain with respect to the capture of juvenile fish and sustainable man
agement of tropical mixed species bottom trawl fisheries.

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ICES WGFTFB REPORT 2008
· It is hoped that a second phase project will be implemented and broadened
to a greater number of countries and incorporating a broader range of
management tools to manage multi species trawl fisheries.
1
Directive
The directive of the WGFTFB is to initiate and review investigations of scientists and
technologists concerned with all aspects of the design, planning and testing of fishing
gears used in abundance estimation, selective fishing gears used in bycatch and dis
card reduction; and environmentally benign fishing gears and methods used to re
duce impact on bottom habitats and other nontarget ecosystem components. Areas
of focus should also include behavioural, statistical and capture topics.
The Working Groups activities shall focus on all measurements and observations
pertaining to both scientific and commercial fishing gears, design and statistical
methods and operations including benthic impacts, vessels and behaviour of fish in
relation to fishing operations. The Working Group shall provide advice on applica
tion of these techniques to aquatic ecologists, assessment biologists, fishery managers
and industry.
2
Introduction
Chair:
Dominic Rihan,

Bord Iascaigh Mhara,

PO Box 12

Crofton Road

Dun Laoghaire

Co. Dublin

Ireland

mailto:rihan@bim.ie
Rapporteur:
Huseyin Ozbilgin

Mersin University,

Fisheries Faculty,

Yenisehir Campus,

Mersin, 33169

Turkey

mailto:huseyin.ozbilgin@ege.edu.tr

Venue:
Tórshavn, Faroe Islands
Date:
21­25 April 2008
2.1
Terms of Reference
The ICES­FAO Working Group on Fishing Technology and Fish Behaviour
[WGFTFB] (Chair: Dominic Rihan, Ireland) will meet from 21­25 April 2008 in Tór
shavn, Faroe Islands.
Topics
a ) The Topic Group on "Application of fish behaviour for species separa
tion in demersal fish trawls" will continue to work by correspondence
following an agreed Action Plan timetable and report to the WGFTFB
in 2008 to:

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ICES WGFTFB REPORT 2008
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· Identify recent behavioural and gear research into the separation of
groundfish species in demersal trawl gears;
· Identify basic principles, strategies and effectiveness of groundfish
species separation techniques such as separator panels, grids and foot
rope modifications.
Conveners: Pingguo He, (USA) and Mike Pol (USA)
b ) Term of Reference on "Incorporation of Fishing Technology Is
sues/Expertise into Management Advice."
Based on the questionnaire exercise carried out in 2005/06 and 2006/07 into develop
ments in fleet dynamics etc, WGFTFB recommends that the topic group continue to
carry out this survey on an annual basis, taking account recommendations received
from WGSSDS.
Conveners: Dave Reid, FRS, Scotland, Norman Graham, MI, Ireland, Dominic Rihan, BIM,
Ireland
c ) A WGFTFB topic group of experts will be formed to consider the draft
ICES Static Gear Manual.
The group will have the following ToRs:
· Review the current draft of the Static Gear Manual;
· Review available literature on the measurement of selectivity of all
Static Gears and identify gaps in the knowledge; and
· Agree a structure for the completion of the manual and identify a
drafting committee to complete this task.
Conveners: Andy Revill, CEFAS, UK and Rene Holst, DIFRES, Denmark
d ) A WGFTFB topic group of experts will be formed with the following
ToRs:
· Identify fisheries where technical mitigation measures have been in
troduced to reduce the bycatch of protected species; and
· Review the efficacy of these technical mitigation measures introduced
to reduce the bycatch of protected species such as small cetaceans or
turtles.
Conveners: Alessandro Lucchetti, ISMARCNR, Italy, Antonello Sala, ISMARCNR, Italy
and Dominic Rihan, BIM, Ireland.
e ) A WGFTFB topic group of experts will work by correspondence to ad
dress the following ToR from WGEF:
· Provide more details on the bycatch of rays in outrigger trawls and
· Review temporal changes in the fishing patterns of high seas pelagic fish
eries taking pelagic sharks.
f ) A WGFTFB ad hoc group will work by correspondence and meet at
WGFTFB meeting in April 2008 to address the following Tor's received
from NIPAG & STACREC:
· To determine whether twin shrimp trawls (e.g. number of meshes in
circumference) are different from single trawls. This would include in
vestigations of the use of twin and triple trawls in other fisheries as

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ICES WGFTFB REPORT 2008
well, for example Greenland halibut directed fisheries, where their de
ployment may be used to improve catch rate rather than catch quality.
· To study the efficiency of twin trawls and determine how best to rep
resent the effort of these trawls for management purposes.
g ) A WGFTFB topic group of experts will be formed to address the fol
lowing ToR received from WGECO as part of the OSPAR Quality
Status Report 2010:
· For each OSPAR region, select and succinctly describe one or more repre
sentative examples of gear modifications, which have resulted in changes
to the ecosystem effects of these gears, including if possible a range of eco
system components.
Conveners: Jochen Depestele, ILVO, Belgium
2.2
Participants
A full list of participants is given in Annex 1.
2.3
Explanatory note on meeting and report structure
The approach adopted in 2004 of addressing specific TOR's was adopted for the 2008
meeting. Individual conveners were appointed during 2007 to oversee and facilitate
work by correspondence throughout the year. The Chair asked the convener of each
ToR to prepare a working document, reviewing the current state of the art, summa
rising the principal findings, identifying gaps in the knowledge where consultation
with other experts was required and recommending future research needs.
Two days were allocated for the conveners and members of the individual Topic
Groups to meet, finalise their reports and findings, and produce a presentation to the
WG and prepare a final report for inclusion in the FTFB report. The summaries and
recommendations for the working documents for each ToR were reviewed by
WGFTFB and were accepted, rejected or modified accordingly to reflect the views of
the WGFTFB. However, the contents of these working documents do not necessarily
reflect the opinion of the WGFTFB. In addition to the presentation of the review re
port, where appropriate, each convener was asked to select a small number (~3) of
individual presentations based on specific research programmes. The abstracts are
included in this report, together with the authors' names and affiliations. Although
discussion relating to the individual presentations was encouraged and some of the
comments are included in the text of this report, the contents of the individual ab
stracts were NOT discussed fully by the group, and as such they do not necessarily
reflect the views of the WGFTFB.
The chair outlined that were possible this format will be adopted for the foreseeable
future. The agenda for the 2008 is as presented in Annex 2.
3
WGFTFB advice and requests during 2007­2008
Overview
During 2007/2008, WGFTFB dealt with the following requests for advice:
· Request from WGEF
· EU request on Baltic Cod Selectivity
· Request from WGSSDS on selection patterns

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ICES WGFTFB REPORT 2008
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· Request from ACE on VMS data usage and buffer zones
·
· EU meeting with net manufacturers
· SGMIXMAN
· AMAWGC
· TOR from SGBYC
3.1.1 WGEF Request on Outrigger Trawls
WGFTFB received a request from WGEF to consider the following "provide more de
tails on the bycatch of rays in outrigger trawls".
Vanderperren (2008) reports the results from a study carried out in Belgium aimed at
testing the use of outrigger trawls in different areas as an alternative to traditional
beam trawls. Outrigger trawling as a fishing method replaces the two heavy steel
beams on each side normally towed by beam trawlers with two lighter demersal
trawls each with its own set of trawl doors. The main benefit is the reduced drag of
the lighter gear resulting in a reduction in fuel consumption. Other likely benefits are
reduced benthic impact, improved fish quality, diversification into non pressure
stock species and increased profitability.
This study details the catches of three Belgian beam trawlers and one Eurocutter,
ranging in sizes from 24m35m LOA and 300hp1200hp mainly fishing in ICES Areas
VIIf, VIIg and IVc, but also in IVb, VIa, VIIa, VIIb, VIId, VIIe and VIIh over the period
Q2 2006 to Q2 2007. Mean catch efficiency for the four vessels expressed as kg
fish/fishing hour are reported and catches of ray species are found to range from
12.58kg ­ 25.96kg (average 19.34kg) for the four vessels (See Table 1). In terms of
overall catch composition ray represented between 32.35%45.07% (average 36.65%)
of the total catch by weight for the four vessels (See Table 2). The results show ray to
be the most important target species based on weight. No breakdown by ray species
is given and no discard data for ray are available at this time, although it is likely the
majority of the catch is marketable fish. For one of the trials vessels (35m/1200p) the
catch composition by ICES area is reported as shown in Table 3.
Table 1. Catch efficiency by species and vessel (marketable catch only).
Catch
efficiency
(kg/fish/fishing
hour)
Species
Vessel 1
Vessel 2
Vessel 3
Vessel 4
Ray sp
12.6
23.5
15.4
26
Dogfish
2.7
3.2
3.4
3.7
Plaice
6.1
5.8
6.7
11.2
Sole
3.2
7
5.2
6.5
Lemon Sole
2.1
0.5
1.3
1.2
Anglerfish
1.1
0.1
1.4
1.8
Other Species
10.5
11.5
14.6
21.2

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ICES WGFTFB REPORT 2008
Table 2. Catch composition by vessel.

Catch composition (%)
Species
Vessel 1
Vessel 2
Vessel 3
Vessel 4
Ray sp
32.9%
45.1%
32.4%
36.3%
Dogfish
7.1%
6.1%
7.2%
5.2%
Plaice
15.9%
11.9%
14%
15.6%
Sole
8.2%
13.4%
11%
9.1%
Lemon Sole
5.6%
1%
2.6%
1.7%
Anglerfish
2.9%
0.2%
3%
2.5%
Other Species
27.4%
22.2%
29.8%
29.6
Table 3. Catch composition by ICES Area for one outrigger vessel (35m/1200hp).

Catch Composition (%)
Species
IVb
IVc
VIIa
VIIb
VIId
VIIe
VIIf
VIIg
VIIJ
Total
Ray sp.
0%
13.6%
37.8%
29.8%
59.7%
0%
50.2%
45%
0%
36.3%
Plaice
44.5%
6%
20.8%
0%
3.2%
32.3%
14%
6.7%
0%
15.6%
Sole
1.1%
22%
16.9%
0%
3.1%
8.4%
13.5%
7.5%
0%
9.1%
Norway
38.6%
0%
0%
0%
0%
0%
0%
0.3%
0%
6.2%
Lobster
Dogfish
0%
12%
4.2%
3.9%
0.7%
13.1%
1.3%
7.7%
20.7%
5.2%
Anglerfish
0%
0.1%
3.3%
17%
0%
1.4%
0.4%
3.8%
32.6%
2.5%
Lemon
0.1%
1.5%
0.3%
14.9%
0.3%
0.7%
1.3%
2.6%
10.9%
1.7%
Sole
Turbot
2.8%
1.7%
1.7%
0%
0.5%
0.3%
1.4%
1.2%
0%
1.4%
Others
12.9%
43.1%
15%
34.4%
32.5%
43.8%
18.9%
25.2%
35.8%
22%
Based on these catches, ray appear to be the most important species by weight in
ICES Areas VIId (59.7%) and VIIf (50.2%) but are also the dominant species in ICES
Areas VIIa, VIIb and VIIg. No rays were caught in Areas IVb and VIIe or VIIj. Taking
catch by different quarter for the same vessel over the period Q4 2006 ­ Q3 2007, ray
are the dominant species forming 36.1%, 25.7%, 35.6% and 41.1% of the total catch
composition respectively.
A short trial carried out by Seafish in the UK, carried out in the south west of England
to investigate the effectiveness of outrigger trawls in lowering fuel costs, and indi
cated similar results with ray forming a high proportion of the overall catch composi
tion. This trial also indicated a reduction of discarding with the outrigger trawl. Total
discards from single basket samples taken for each of the nine hauls carried out dur
ing the trial amounted to an average of 59% by volume, compared with 71% meas
ured from beam trawlers from comparable surveys (Cornwall Fisheries Resource
Centre, 2007).
The Dutch fishing industry has conducted experimental trials with outrigger trawls
from February till October 2006 to investigate the possibilities for lowering fuel costs.
Four beam trawlers (1350hp ­ 2000hp) have conducted experiments in the North Sea.
The Dutch outriggers are, in contrast with Belgian and UK vessels, specifically target
ing plaice and/or Norway lobster, in all quarters except for the winter period. Catches
of Norway lobster are 4 to 5 times higher than catches of beam trawlers. More valu

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ICES WGFTFB REPORT 2008
| 9
able fish species, such as sole, brill and turbot are only caught in small quantities
compared to beam trawlers, but the catches of plaice are comparable (Bult & Schelvis
Smit, 2007). No data are provided, however, on ray species.
There are a number of potential reasons for the increased ray catch with the outrigger
trawl, which relate to changes in fishing behaviour or differences in the dynamics of
the outrigger trawl gear as follows:
1 ) The outrigger trawl is not as effective at catching sole and there is evidence
that Belgian and UK fishermen have specifically targeted rays using out
rigger trawls to compensate for the decrease in sole catch. In the beam
trawl fishery rays were always considered a bycatch species. There are no
indications that Dutch fishermen compensate their reduced catch of valu
able species by higher ray catches.
2 ) Vessels involved in this trial regardless of horsepower have been allowed
to fish inside the 12 mile and in certain areas this may lead to high ray
catches (Polet et al., 2007) given there are known to be local populations in
side 12 miles e.g. Irish Sea.
3 ) The main difference in the outrigger gear and beam trawls is the reduced
weight and reduced fishing speed, giving rise to a substantial fuel saving,
and the increase in spread. In the Seafish trials gear monitoring equipment
installed on the gear recorded from 7­9m of spread between the doors per
side, with a relatively small net, whereas vessels would be restricted to a
4m beam fishing the same area inside the 12 mile limit. This increased
spread and ground coverage is likely to improve catch efficiency for spe
cies such as ray.
4 ) An abundance of larger rays observed in the outrigger catches compared
with beam trawls may be a result of the differences in groundgears be
tween the beam trawl and outrigger trawl (Richard Caslake, pers. comm.).
In conclusion the Belgian and UK trials suggest the use of outrigger trawls may lead
to an increase in the catch of rays, particularly when vessels specifically target these
species. However, it should be stressed that the results also suggest that the use of the
outrigger trawl is an economically viable option for smaller vessels (e.g. Eurocutter
vessel) fishery, while for larger vessels viability due to reduced sole catches is at best
marginal. Polet et al. (2007) and Vandeperren (2008) also highlight some technical
limitations with this gear for larger vessels relating to gear spread. In practice this
means, at least in the short term, the uptake for this gear will be limited to smaller
vessels in Belgium and the impact on ray stocks maybe not that significant although
needs monitoring. This may not necessarily be the case in the UK, where indications
are that large beam trawl vessels may adopt this gear, due to fuel costs.
3.1.2 EU request on Baltic Cod Selectivity
The technical measures regulation for the Baltic Sea (EC No 2187/2005) requires the
European Commission to present an evaluation of the selectivity of active gears tar
geting cod in the Baltic Sea in 2007. The Commission has requested that ICES advise
on this issue as follows:
"ICES is requested to evaluate the selectivity of active gears on cod for which cod is recognised
as the target species. Those gears are: Trawls, Danish seines and similar gear with a mesh size
105mm with either a Bacoma exit window or a T90 codend as defined in regulation (EC) No
2187/2005.

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10 |
ICES WGFTFB REPORT 2008
The evaluation should include a comparison of the T90 codend and the Bacoma exit
windows concerning their selectivity for cod:
a ) In general;
b ) With regards to the minimum landing size of 38cm;
c ) The rate of discarding;
d ) Any additional aspect that ICES may consider desirable in this context.
ICES is specifically requested to advise on the acceptance of the existing gear specifications by
the industry and whether they conform to the existing obligations and measures for cod man
agement in the Baltic".
The ICES WGFTFB has addressed this request by soliciting input from a number of
specific experts with information and/or comments received from Denmark, Sweden,
Poland, Germany, Finland, Latvia and Ireland (former Chair of WGFTFB). The Chair
of WGFTFB has taken this information and produced a response as an attempt at ad
dressing the EU's specific request.
Based on the information received WGFTFB concluded the following:
3.1.2.1 General Comments
· On the basis of an earlier metaanalysis carried out by ICES, both Bacoma
windows and T90 codends (provided they are correctly used as per the
current regulations) give 50% retention lengths of 38­40cm, equivalent to
the MLS for cod of 38cm. There is inherent variability in the data sets used
in this analysis, however, and this should be borne in mind.
· In order to make a direct comparison between the gear options, data from
structured experiments, specifically designed to assess the relative selectiv
ity of the two designs is still required. In particular robust data on the ef
fect of twine thickness, codend circumference and mesh size needs to be
collected given the inherent effect of such parameters on the selectivity of
the respective gear options.
· A preliminary analysis of new data provided by Poland and Germany give
similar L50s of ~ 41cm and Selection Ranges of between 4.8­6.5cm and re
affirm the selective properties of T90 codends.
· A modelling analysis carried out in Denmark indicates that codend cir
cumference has a major bearing on selectivity regardless of whether the
codend is constructed in standard diamond mesh or T90.
· Only limited additional information on the selectivity of Bacoma windows
is available and the results of the earlier metaanalysis are considered as
the most reliable estimates.
3.1.2.2 Selectivity with Regard to Minimum Landing Size of 38cm
· Both gear options give L50s equivalent to the MLS for cod but based on the
available information the likelihood of either gear fully corresponding to
the management aim of bringing the MLS into agreement with L25 in all
areas of the Baltic is still unclear. This is due, in part to the high degree of
data variability and other factors such as catch size and catch composition.
· Complimentary technical measures such as realtime closures maybe ap
propriate in areas where high concentrations of cod are encountered or re
stricted fishing in areas where flatfish catches are high and the
effectiveness of the gear measures maybe negated.

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ICES WGFTFB REPORT 2008
| 11
3.1.2.3 The Rate of Discarding
· Unless coverage by observer schemes is extensive compared to overall
fishing effort, it is very doubtful that the available discard data will be suf
ficient to allow detection of gearspecific differences in discard rates. De
tection of any differences will be exacerbated by localised differences (i.e.
different fleets using T90 or Bacoma in different areas, fishing on different
size distributions and catch compositions).
· The limited information available from recent research cruises and discard
sampling data indicates similar discard rates of 5­10% for both gear alter
natives.
· The effect on selectivity of large catch sizes and differing catch composi
tions with both gear options needs to be considered, as there is evidence
that both are contributing factors to high discard rates.
3.1.2.4 Additional Aspects
· The available information suggests a dichotomy between countries such as
Denmark and Sweden whose fishermen prefer to use the Bacoma window
and other countries particularly Poland and Germany where the T90
codend is the more attractive alternative.
· There are allegations of circumvention of the gear measures but without
documented evidence no assessment of the impact of such practices on se
lectivity can be made.
· Both gears have their advantages and disadvantages in terms of practical
ity or perceived benefits in terms of fish quality or fuel efficiency. These are
of limited relevance from a stock management perspective but may offer
incentives for fishermen to adopt the selective gear options.
· Given the likely negative effects on selectivity, a review of the current
regulations regarding permissible gear attachments e.g. chafers, rescue
floats etc. should be carried out in order to establish whether there is a
need for their continued usage.
Because limited resources were available, only a preliminary analysis could be car
ried out which, for the most part, served to identify potential data sources for a com
prehensive analysis. From a review of all existing literature, only limited selectivity
data were found for the fisheries covered by WGSSDS. The majority of these data
were historic and may not necessarily represent current fishing practice (i.e. gear
type, codend mesh size/material) or stock structures. The summary data identified is
shown in Table 4 below. Raw data is available for the Irish trials.
This report was forwarded to ICES and STECF. STECF carried out their own analysis
and concluded the following:
"STECF supports the ICES findings and concludes that it has not been possible on basis of the
available information to answer the question if the Bacoma and the T90 trawls have similar
selectivity properties. Answering the question would require a series of coordinated experi
ments".
"STECF notes that the current exploitation pattern on cod of the trawl fishery allows the ex
ploitation of immature cod. This result in a suboptimal utilisation of the cod stocks in the Bal
tic. Improved exploitation pattern with reduced mortality on juveniles will not only provide
for higher yields but also contribute to the recovery of the eastern cod stock. Therefore STECF

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12 |
ICES WGFTFB REPORT 2008
recommends that measures resulting in improved exploitation pattern for Baltic cod be con
sidered".
3.1.3 Request from WGSSDS on selection patterns
Prior to the 2008 WGFTFB meeting in the Faroe Islands, request from WGSSDS to
provide gear selection curves for species with high discard rates was examined.
Limited resources meant that only a preliminary analysis could be carried out, which
primarily identified potential data sources for a much more comprehensive analysis.
From a review of all existing literature, only limited selectivity data was found for the
fisheries covered by WGSSDS with the majority being historic data, which may not
necessarily represent current fishing practice (i.e. gear type, codend mesh
size/material) or stock structures. The summary data identified is shown in Table 4
below. Raw data is available for the Irish trials.
Table 4. Summary Selectivity Data.
Species Country Area Date Gear
Mesh Size
L50
SR
Type
Haddock1
Ireland
VIIj
08/2004
SSC
90mm x
30.14
8.31
6mm
single
Haddock1
Ireland
VIIj
08/2004
SSC
100mm x
34.47
7.34
6mm
single
Haddock1
Ireland
VIIj
08/2004
SSC
110mm x
36.87
11.36
6mm
single
Whiting2
Ireland
VIIg
02/1996
OTB
90mm x
23.06
11.64
4mm
single
Haddock2
Ireland
VIIg
02/1996
OTB
90mm x
19.09
12.73
4mm
single
Plaice2
Ireland
VIIg
02/1996
OTB
90mm x
16.80
5.46
4mm
single
Megrim2
Ireland
VIIg
02/1996
OTB
90mm x
19.52
7.62
4mm
single
Whiting 2
Ireland
VIIg
04/1996
OTB
90mm x
32.72
12.36
4mm
single
with
90mm
SMP
Hake3
Spain
VIIIa
12/1998
OTB
70mm x
30
10.95
double
4mm
Hake3
Spain
VIIIa
05/1999
OTB
70mm x
27.2
13.45
double
4mm
Hake3
Spain
VIIIa,b
07/1999
OTB
70mm x
30.3
1.16
double
4mm

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ICES WGFTFB REPORT 2008
| 13
Species Country Area Date Gear
Mesh Size
L50
SR
Type
Hake3
Spain
VIIIa,b
11/1999
OTB
70mm x
30.7
5.94
double
4mm
Hake4
Spain
VIIIa
1999
OTB
80mm
23.5
13.3
Hake4
Spain
VIIIa
1999
OTB
100mm
46.2
18.6
Hake4
Spain
VIIIb,d
1999
PTB
80mm
22.6
19.2
Hake4
Spain
VIIIb.d
1999
PTB
100mm
34.6
6.6
Megrim4
Spain
VIIIa
1999
OTB
80mm PA
20.1
2.5
Megrim4
Spain
VIIIb,d
1985
OTB
60mm PA
12.8
6.4
Megrim4
Spain
VIIIb,d
1985
OTB
70mm PA
20.8
9.1
Megrim4
Spain
VIIIb,d
1985
OTB
60mm PA
13.0
5.3
Megrim4
Spain
VIIIb,d
1985
OTB
70mm PA
20.3
6.1
1 Anon., 2005; 2 Anon., 1997; 3 Puente., 2001; 4 Meixide and Pereiro., 1997.
In addition there are a number of catch comparison datasets available from Ireland
and France on a range of species, fisheries, gears and codend mesh sizes. These data
sets provide simple length frequency data but no L50s. A simple method based on
Generalised Liner Mixed Models (GLMM) has recently been developed by Revill and
Holst (in prep.) that allows a better analysis of catch comparison data. This method
uses polynomial approximations to fit the proportions caught in control and test
codends. This method was presented at FTFB as a new method of analysis and some
of these datasets could be run through this model if required. Catch comparison data
sets available that could be looked at are shown in Table 5.
Table 5. Catch Comparison Data Available.
Species Country Area Year Gear
type
Experiment
details
Whiting,
Ireland
VIIg
2003
OTB (Twin
Inclined
Haddock,
rig)
Separator Panel
Hake
vs 80 mm x
6 mm single
codend
Whiting, cod,
Ireland
VIIg
2000
OTB (twin
Inclined
haddock
rig)
separator panel
vs 80 mm x
3.5 mm single
codend
Whiting,
Ireland
VIIg, VIIj
2000
OTB
Inclined
haddock
separator panel
vs 80 mm x
3.5mm single
codend
Whiting,
Ireland
VIIj
2000/2001
SSC
90 mm Codend
haddock,
with 90 mm
hake
SMP vs 80 mm x
4mm single
codend
Whiting,
Ireland
VIIg
2002
SSC
100 mm x 4 mm
haddock,
double vs 80
hake, cod
mm x 4 mm
single

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14 |
ICES WGFTFB REPORT 2008
Species Country Area Year Gear
type
Experiment
details
Haddock,
Ireland
VIIg
2002
SSC
Large mesh top
Whiting,
sheet net/80 mm
Hake
x 6 mm codend
vs standrad
seine/80 mm x 6
mm codend
Haddock
Ireland
VIIj
2001
OTB
100 mm x single
6 mm; 100 mm x
double 4 mm;
110 mm x single
6 mm vs 80mm
x 6 mm single
Monkfish
Ireland
VIIg,VIIj
2002
OTB (Twin
Bottom sheet
rig)
escape
panel/100 mm x
6 mm codend vs
100 mm x 6 mm
codend
Nephrops,
France
VIIIa,b
2003/2004
OTB
Flexible grid/70
hake
mm x 4 mm
codend vs 70
mm codend
Nephrops,
France
VIIIa,b
2006
OTB
Flexible
hake
grid/70mm x 4
mm codend vs
70 mm codend
Nephrops,
France
VIIIa,b
2006
OTB
80 mm x 4 mm
hake
vs 70 mm x 4
mm
Nephrops,
France
VIIIa,b
2006
OTB
70 mm x 4 mm
hake
with 70 mm
SMPvs 70 mm x
4 mm
Monkfish,
France
VIIIa,b
1993
OTB
Monkish sorting
Megrim, ray
grid vs 70 mm x
4 mm codend
Monkfish,
France
VIIh, VIIIa
1997
OTB (Twin
Monkfish
megrim, ray
rig)
sorting grid vs
70 mm x 4 mm
codend

In 2008 the EU will focus on mitigation of discards associated with a key number of
fisheries in community waters. Given part of this process will be to identify candidate
technical measures suitable for these fisheries which will achieve measurable targeted
reductions, the whole area of gear selectivity will be revisited by FTFB and also in
other fora such as MariFish and STECF. A specific ToR was agreed at FTFB for 2009
which aims:
"To review and appraise the current selectivity characteristics of the gears used in the
fisheries identified by the EU as candidate fisheries"; and
"To propose potential gear modifications that could contribute to the future technical
conservation measures needed to achieve the targets proposed by the EU".

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ICES WGFTFB REPORT 2008
| 15
It should be noted that, given one of the candidate fisheries selected by the EU is
Nephrops fisheries in the Celtic Sea, further analysis of the selectivity of gears used in
these fisheries will be carried out, and this should be of assistance to WGSSDS.
3.2
Request from ACE on the use of VMS data
There was a suggestion by ACE for a new EG to work by correspondence to look into
e.g. the availability of VMS data, interpretation of these data and the potential for set
ting up buffer zones for MPAs using this kind of data. It was suggested that relevant
ToRs that might otherwise be dealt with by WGDEC be directed instead to this new
group.
It was concluded that fishery technologists should be involved with this work and
the following ToR was directed to WGFTFB:
"For a range of representative fishing gears operating on offshore waters, begin a considera
tion of the fishing methods employed (including water depth, warp length, frequency of VMS
returns and positional relationship between trawl and vessel) that will influence the dimen
sions of `buffer zones' around Marine Protected Areas to ensure that trawls do not damage the
seabed."
No action to date has been taken on this request and FTFB await direction from the
Secretariat regarding required input from FTFB. The comment was made that there is
extensive work going on in this area in the US and this may be useful as reference
material.
3.3
Meeting of WGFTFB Chair with EU Commission and Net manufacturers on
technical measures regulations
In July 2007, the WGFTFB met with net manufacturers and the EU at the invitation of
the EU to discuss the revision of the Technical Conservation Measures regulations
currently being undertaken by the Commission. Nine net manufacturers attended
this meeting, representing the Northeast Atlantic, Bay of Biscay, Mediterranean,
North Sea and Skagerrak and Kattegat. A range of issues were discussed at this meet
ing as summarised below:
1 ) Codend Definition: The current definition of codends and/or extension
piece has been identified as being confusing, given the differences in ter
minology used in different countries and also differences in trawl design.
The Commission are therefore proposing to redefine "codend" as being
the last 8 0r 10 metres of the trawl (bottom trawls) only and possibly the
last 20m30m of a pelagic trawl. This would very much be seen as a length
for regulatory purposes ("Enforcement length") i.e. codend circumference,
twine thickness, mesh size, attachment legislation would apply to this
length. There is also consideration of including a minimum mesh size for
the whole trawl i.e. in a demersal trawl no mesh can be less than 80mm.
Such a condition exists in the Baltic. There was general support for these
proposals by the netmakers, except concerns about the implications for
nephrops trawls if the codend mesh size was increased to 100mm for in
stance in the future, most fishermen would have to replace the bottom
wings and belly sheets, given these are still constructed in 70­80mm cur
rently. There was also some concern regarding pelagic codends given their
design and the need for a "pumping" section.
2 ) Twine Thickness: There is acceptance by the EU that the current regula
tions on twine thickness are unworkable and the measuring methodology

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16 |
ICES WGFTFB REPORT 2008
unenforceable and too subjective. While there is undoubtedly some corre
lation between selectivity and twine thickness/stiffness, the EU have iden
tified that there are easier parameters that have an effect on selectivity that
can be better controlled. The netmakers made the point that basically the
twine thickness of twine they provided depended on the customer ­ give
the customer what he wants! The EU proposal is to retain a maximum
twine thickness, harmonised by areas but would probably amend the
measurement methodology. Labelling/Certification is seen as having a role
in ensuring twine thickness.
3 ) Codend Circumference: The EU have identified codend circumference as
having a major bearing and selectivity, largely on the basis of a recent
STECF subgroup meeting. They are intent on harmonising the codend cir
cumference regulations for demersal gears and the proposed start point is
for a max. of 100 meshes for all gears with a mesh size greater than
70/80mm. The netmakers did not voice any strong objections to this, al
though more research is needed for the smaller mesh sizes in order to sat
isfy strength and excessive narrowing of codends.
4 ) Strengthening Bags: Again the EU has identified strengthening bags as
detrimental to selectivity and are intent on prohibiting their use. They ac
cept that are some countries where there use is widespread and would ac
cept derogations if a case could be made on safety grounds. However, the
majority of the netmakers did not see this as a major problem (except Ire
land in the nephrops fishery) although stressed the need for some research
to address these concerns. The issue of attachments such as chafers, round
straps and strengthening ropes was raised and the point was made that
topside chafers in particular have a detrimental effect on selectivity. The
EU agreed to look at this regulation and amend accordingly.
5 ) Selective Devices: The use of selective devices should be encouraged in the
new regulations but specific details would probably be based contained in
Commission regulations. Two major issues were raised regarding Square
Mesh Panels ­ position and joining ratio. The EU seem intent on introduc
ing a regulation on position at around 5­6m from the codend to fit in with
the codend definition but this position could be altered on a regional basis
to match specific fishery problems. Joining ratio was felt important but the
current 2:1 ratio seems okay except where there are significant changes in
mesh sizes i.e. 120mm into 80mm mesh. The issue of measurement of
square mesh was also raised, as there seems to some differences in meth
odologies being adopted by different inspectorates. The question of ap
propriate material was discussed and the netmakers felt that both knotted
and knotless twine could be used as long as the material used was of a
good quality and relatively stiff to maintain shape. There was a lengthy
debate on the relative merits of BACOMA vs. T90 and a concern was ex
pressed that the current regulations did not facilitate the use of T90 sec
tions above the codend. The EU seemed broadly in favour of the use of
T90.The Dutch netmaker reported on trials with hexagonal mesh codends
for release of juvenile horse mackerel.
6 ) Codend Geometry: There was no major debate on this issue, except it was
felt that the current regulations requiring cylindrical codends should apply
only to demersal trawls given the differences in designs of pelagic
codends, which are often purposely built cone shaped or have wider sec

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ICES WGFTFB REPORT 2008
| 17
tions fro fish quality and to facilitate pumping. The EU accepted this as
sensible.
7 ) Certification/Labelling: There was a general discussion on the possibility of
netmakers certifying netting/codends sold to fishermen. The netmakers felt
in principle this was feasible to a certain degree i.e. particularly mesh size
but did not want to have an legal responsibility once the codend left the
factory as they had no control of how fishermen would use the codend
subsequently. They were in favour of adoption of the OMEGA gauge
given its accuracy and saw this as an integral part of a certification scheme.
They agreed collectively to examine this issue more closely and report back
to the EU. The EU also mentioned the meeting in Bergen on ISO standards
for netting, although none of the netmakers seemed to be aware of this
meeting.
8 ) General Points: The netmakers stressed the need to consider pelagics and
demersal trawls separately and not generalise. The issues in pelagic trawls
are generally not selectivity issues but for fish quality and optimum water
flow. The EU accepted this as reasonable and agreed to ensure this was
taken account of in the new regulations.
3.4
SGMIXMAN
The Chair of WGFTFB participated in the Study Group on Mixed Management
(SGMIXMAN) meeting in January 2008 at the request of the Chair. At this meeting
the continuing input by FTFB to the Assessment Working Groups and appropriate
approaches for provision of this input were discussed. A lot of this information has
direct relevance to the work of SGMIXMAN and other Expert Groups, in addressing
some of the data constraints/deficiencies currently associated with the provision of
fisheriesbased advice. WGFTFB has strived to provide quantified information
but still struggles with how to relate the knowledge (albeit subjective at times) gear
technologists have with the signals and trends observed by stock assessment scien
tists.
Put
simply
FTFB
can
identify/verify
problems or
changes
not necessarily detected elsewhere but cannot always quantify the effect as a Work
ing Group because the members do not necessarily have access to the detailed data
catch or effort data or have the time or skills to do a more complex analysis. A com
bination of these factors has meant that a lot of this information is lost in the advisory
process but nonetheless given that ICES provides stock assessments for only ~ 50% of
stocks currently, the need to look at such "soft" fisheries information is still consid
ered necessary by FTFB and this was stressed to SGMIXMAN.
In addition to the provision of fishery information, the issue of effort measurement
was also raised by the Chair. This has wider implications for stock assessment than
just the development of mixed fisheries management models and FTFB have identi
fied this as a major issue with current management systems for a number of years.
This is a complex issue that will not be solved in the immediate future. However, the
Chair outlined the ToRs of the Study Group on combining gear parameters into effort
and capacity metrics (SGGEM) which was established by FTC to address this issue.
3.5
AMAWGC
The Chair of WGFTFB participated in AMAWGC in February 2007 to discuss the
provision of fisheries information. As in 2007 the Assessment Chairs were supportive
of the efforts of FTFB although again stressed the need for better quantification of the
information. There was also a discussion about the new Benchmark Workshops that

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18 |
ICES WGFTFB REPORT 2008
have been introduced into the Assessment process. It was felt that this could be an
appropriate forum for formulation and integration of FTFB information.
3.6
SGBYC
The Chair of WGFTFB participated in the Study Group for Bycatch of Protected Spe
cies (SGBYC) in January 2008. The main issue of relevance to FTFB was ToR a):
"Review of methods and technologies that have been used to minimise bycatch of species
of interest, including methods that have failed".
This term of reference is linked to ToR (d) addressed by WGFTFB (Section 13). The Study
Group compiled a preliminary list of methods and technologies that have been used
to minimise bycatches of species of concern, and spent time reviewing the problems
associated with the application of pingers (acoustic deterrent devices) in static gear as
a cetacean bycatch mitigation measure. Although mandated in the US and EU, pinger
deployment has proven difficult to implement for a variety of reasons. In reviewing
these reasons, the Study Group proposed a framework for the development and im
plementation of future mitigation measures. The SG recommended that any further
mitigation plans for minimising cetacean or other protected species bycatches should
be introduced only after careful consideration of all of the above mentioned factors.
4
ICES draft science plan 2007­2013
Bill Karp the FTC Chair led a discussion on the ICES Draft Science Plan 2008­2013.
The discussion mainly centred on the 17 identified themes and the prioritisation of
seven of these themes. Apart from one of these seven themes, the remit of WGFTFB is
largely outside these priority areas and therefore concerns were expressed by FTFB
members that there was a danger participation in the Group may diminish, if Insti
tute Directors do not feel gear technology is considered an important issue by ICES.
There were also concerns expressed regarding the proposal of ICES acting as a project
coordinator in the future. The feeling was that this could bring ICES into direct con
flict with national laboratories. The conclusion from this debate was that while
WGFTFB supported the need for change within the ICES structure, the seeming de
motion of fisheries assessment and measurement of fisheries impact was felt a danger
to the continued existence of the Working Group. A response to this plan was drafted
by Bill Karp and WG chair taking account submissions from other WGFTFB and
WGFAST members. This response was forwarded to ICES Secretariat.
5
Report from Study Group on the Development of Fish Pots for
Commercial Fisheries and Survey Purposes (SGPOT)
The Study Group on the Development of Fish Pots for Commercial Fisheries and
Survey Purposes (SGPOT) SGPOT was proposed by the topic group on Alternative
fishing gears that met at the FTFB meeting in 2005 and 2006. SGPOT had its first
meeting 21­22 April 2007 in Dublin, Ireland and this second meeting was held in Tór
shavn, Faroe Islands 19­20 April 2008 prior to the FTFB meeting.
The group work was attended by 24 participants representing 14 countries. The
agenda followed the Terms of Reference closely.
A review of worldwide use of fish pots that was initiated at last year meeting was
continued. It seems difficult to identify worldwide catch data for fish pots as these are
generally mixed with other gears. In order to partly address this the group decided to
make an extensive list of use of fish pots in commercial use, as research tool and

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emerging use of fish pots, as this was felt a valuable platform for exchange of infor
mation.
In a discussion of new fish pot research several examples were presented. In Norway
the twochamber pot has been redesigned with a single entrance and modified to
float off bottom. Trials carried out have yielded a 45% higher catch rate of cod. In
Sweden the deformation of the Norwegian pot when floated off bottom in high cur
rent has been tested in flume tank as this had proved a major problem in Swedish
trials. New attachments and extra buoyancy were tested to counteract deformation
with good results.
A discussion on the fundament research needs on fish behaviour to improve the
catching efficiency and also enhance the use of pots as assessment tools had a slow
start as this seems to be a complex subject and involving a wide variety of variables.
Although it was agreed lessons can be learned from other baited gear, the behav
ioural component is much more important for fish pots. The discussion centered on
attraction variables and what predisposes a fish to be caught and actual capture proc
ess examples were discussed. Group members agreed to further on this issue and
prepare text to be discussed by the Group.
In a discussion on design and ecosystem effects the main issue was ghost fishing and
also the need to develop responsible codes of practice. There was a lengthy discus
sion with regard to design and operation of fish pots.
The terminology to be used for defining fish pots was discussed and it was agreed a
generic figure with common terms will be developed. The group also discussed the
definition of a fish pot as the group had reservations with the draft definition as pre
sented by the FTFB Topic Group on Gear Classification.
The group also discussed gear conflicts, which seems to be one of the main contribu
tors to ghost fishing. Spatial and temporal separation of gears seemed to be the best
method to avoid conflicts but also designs incorporating features such as rounded
corners and few surface lines may reduce conflicts.
The outline of a Cooperative Research Report was discussed and group members
were assigned to prepare text for the report with a deadline of Christmas 2008.
SGPOT will work by correspondence and meet at the FTFB meeting 2009.
6
Report from Working Group on Quantifying All Fishing Mortality
(WGQAF)
Philip MacMullen, Chair of the newlyformed WGQAF, described to FTFB members
the proceedings and recommendations of the first meeting of WGQAF.
The new WG was an evolution from the previous SGUFM, chaired by Mike Breen.
The meeting had involved a series of presentations of background information, re
search results and discussion topics. These included:
· Alan Fréchet ­ Inclusion of Escape Mortality in Stock Assessment,
· Phil MacMullen ­ Industry/Science Solutions in a Data Poor Elasmobranch
Fishery,
· Mike Breen ­ Ghost Fishing in Static Gears (Pots), and
· Irene Huse ­ Purse Seine Slipping Mortality in North Atlantic Mackerel
(and herring).

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ICES WGFTFB REPORT 2008
The WG had also discussed a number of topics in some detail. Most of these explored
the way the WG should operate and future areas of work:
· the inconsistency in dealing with all components of F in stock assessments,
· the need to look at the uncertainty associated with discard & other sources
of mortality data and how this could best be accommodated in the assess
ment process,
· revisiting the definitions of `bycatch' & associated terms,
· the potential importance of industry selfsampling as a means of gaining
more comprehensive mortality data,
· IUU and the potential for obtaining useful information from industry
sources and the supply chain,
· the potential significance of mortality in nonquota and noncommercial
species,
· the use of multispecies and ecosystem monitoring to help identify gaps in
fishing mortality data,
· issues relating to the recovery of lost fishing gears, and
· the need for improved outreach within ICES and at national levels
Future terms of reference would be framed around:
· continued work on application of UM data to stock assessments,
· a review of information on IUU available from fishing companies and op
tions for using same,
· review the status and content of US National Bycatch Report,
· a review of best practices for reducing `collateral' mortality in fisheries,
and
· a review of the potential for self sampling to address mortality questions.
A number of specific actions were also identified
· update reports on incorporation of components of F in stock assessment
through direct contact with WG chairs and AMAWGC,
· developing lines of communication with WGECO,
· proposing a joint topic group on definitions of bycatch & associated terms
with WGFTFB for 2009 meeting,
· to meet for 1­2 days before WGFTFB in 2009, and
· to encourage more (and broader) participation in the WG
7
FAO request for clarification on Bycatch terminology
Over the last four decades, much concern has been expressed by fishery managers
and conservation/environmental groups that bycatch and discards may be contribut
ing to biological overfishing and altering the structure of marine ecosystems. In the
last two decades, the search for solutions to bycatch problems has intensified.
While the term "discards" is self explanatory, the same cannot be said for term "by
catch". In 1992 Murawski1 noted "the use of the term bycatch adds considerable con

1 In Alverson, D.L., Freeberg, M.H., Pope, J.G., Murawski, S.A. A global assessment of fisheries bycatch and dis-
cards. FAO Fisheries Technical Paper. No. 339. Rome, FAO. 1994. 233p.

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fusion to a topic that is already complex to both scientists and managers".... The term
is relatively imprecise in that it constitutes a value judgment and may be inaccurate when
used over any extended time to describe an element within a multispecies catch. In essence,
"yesterdays bycatch may be todays target species."
Presently, there is no international standard definition of bycatch. Some national by
catch definitions exist but there is inconsistency between definitions. Older defini
tions of bycatch include retained incidental species and discards while in more recent
definitions the retained incidental catch is excluded. Some of the changes to bycatch
definitions (e.g. Australia and USA) reflect (i) the trend from single species to multi
species management and (ii) recognition that ghost fishing mortality and encounter
mortality may be high for some gear types in some situations.
The term bycatch is confusing, with protagonists and antagonists in the bycatch de
bate selecting definitions that favour their position.
The need for a coherency on terms used to describe catch components
While there is a broadbased agreement that all species retained for sale should be
part of an effective fisheries management plan and that discards should be mini
mized, the use of the term bycatch in this context is extremely problematic.
From an FAO perspective, a review of definitions and terms would be worthwhile if
it removed the ambiguity associated with terms such as bycatch, target species, inci
dental catch etc. Further, a review would be justified if it led to replacement or revi
sion of terms and that these new terms / revisions were accepted by ICES member
and non member countries.
Accordingly, FAO requests that FTFB to consider the following;
· The compilation and assessment definitions and terms associated with
catch, bycatch and discards;
· Whether the term "bycatch" has outlived its usefulness as a universal de
scriptor of part of the catch;
· The drafting of a new definition(s) of terms used to describe the various
catch components.
8
Update on Gear Classification Topic
The Chair gave an update of the current position regarding the production of a new
gear classification manual as a replacement of the existing 1971 FAO Technical Paper
222. The development of this manual had been a ToR for WGFTFB in 2006 and 2007
and significant progress has been made in completing a final draft. However, a num
ber of factors since the last WGFTFB meeting in 2007 had meant that the process had
now stalled. This was due to the fact that the original conveners of this ToR have ei
ther retired or have taken up positions in the private sector. Also the individual who
had been identified to produce the drawings for the manual had indicated that they
were not now willing to complete this task. The text therefore remains about 90%
complete but no alternative illustrator has been identified. FAO indicated that they
remain committed to the completion the manual and reported to WGFTFB on a pro
posed way forward. This would entail identifying an individual to finishing drafting
text and an alternative illustrator to complete the diagrams. This was agreed by FTFB
as the best way forward. No financial commitment has been made towards publica
tion costs at this stage.

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ICES WGFTFB REPORT 2008
9
WWF Smart Gear Competition
Dr Andy Revill, CEFAS, UK, presented information about the 2007 WWF "Smart
Gear" competition. Initiated by WWF in 2005, the competition the competition has
now 22 worldwide sponsors including private companies such as Mustad and
Sealord as well as research institutes such as CEFAS, DFO and Seafish. The objective
of the competition is to inspire innovative, practical, costeffective ideas that allow
fishermen to fish "smarter" ­ to better target their intended catch while reducing by
catch. The competition is open to all: fishermen, professional gear manufacturers,
teachers, students, engineers, scientists and backyard inventors. The numbers of en
tries received to date have been:
2005: 50 entries from 16 countries
2006: 83 entries from 26 countries
2007: 70 entries from 22 countries
Entries are judged by an international panel made up of gear technologists, fisheries
experts, seafood industry representatives, fishermen, scientists, researchers and con
servationists. The Grand Prize winner for 2007 was the "eliminator" trawl designed
by a team from the US. The "eliminator" trawl was designed to allow access to areas
previously closed because of mixed species fishery, and potential of catching cod. It
has the ability to allow fishermen to access abundant supplies of haddock while
avoiding bycatch of cod. It is currently under assessment and will soon be adopted
into NOAA legislation. The runner up prize went to a birdscaring device called the
"traffic cone" developed in Argentina. This device is currently under trial in the
southern hemisphere with further trials planned in Alaska. The second runnerup
was a nested cylinder bycatch reduction device developed in the US. The designer of
this device is working with WWF, Ocean Conservancy and NOAA Fisheries to assist
with certification trials for Gulf of Mexico shrimp fisheries. There will be no competi
tion in 2008 to allow fund raising and attraction of additional sponsors but it is ex
pected to run in 2009.
10
ToR a): Species Separation in demersal trawls
Conveners: Pingguo He (USA) and Mike Pol (USA)
10.1 General Overview
Bottom trawl fisheries on the both sides of the Atlantic Ocean, as well as in the Medi
terranean Sea, target a number of groundfish species and species groups. Here
"groundfish" includes all fish species targeted by bottom otter trawls. In recent years,
some species in the demersal complex have become heavily exploited while others
have shown good recovery. For example, in the northeastern USA, the New England
Fisheries Management Council reported substantial increases in overall biomass of
twelve managed groundfish species but the growth was not uniform among species
or stocks. Among those stocks, Georges Bank haddock (Melanogrammus aeglefinus)
spawning biomass showed the greatest increase in recent years. On the other hand,
cod (Gadus morhua) stocks are still being "overfished" and experiencing "overfish
ing". Along with the cod stocks, all four yellowtail flounder (Limanda ferruginea)
stocks in the northeastern US are considered as "overfished" and experiencing "over
fishing". This phenomenon of mixed fisheries of healthy and depleted stocks is not
unique to fisheries in the northeastern USA.

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ICES WGFTFB REPORT 2008
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Often, the status of one of the stocks captured in a trawl fishery may call for decreas
ing fishing mortality (e.g. cod and plaice in the North Sea, hake in the Western Atlan
tic and Mediterranean waters and associated recovery plans). Of the mixture of
different fish species encountered and caught, retention of only some species may be
desired.
Excluding such species from catching by separating them early in the fishing process
and releasing them in situ from the net will likely contribute to stock recovery, as sur
vival rates prior to haulback of gear can be high in many cases. Therefore, there is a
need to define, develop, synthesize, and distribute means and strategies to selectively
harvest healthy stocks while causing minimal mortalities to the depleted stocks by
avoiding their interactions with the gear, releasing them at early stages of capture or
at least at fishing depth. This report is a result of a topic group of ICESFAO Working
Group on Fishing Technology and Fish Behaviour which met in 2007 in Dublin, Ire
land and in 2008 in Tórshavn, Faeroe Islands. The report reviews behavioural differ
ences among demersal species near demersal trawls and methods to separate them in
bottom trawl fisheries.
10.2 Terms of Reference
The topic group was charged to:
· Identify recent behavioural and gear research into the separation of
groundfish species in demersal trawl gears;
· Identify basic principles, strategies, and effectiveness of groundfish separa
tion techniques;
Some groundfish species or stocks of these species are in low biomass, or overfished,
while others are in healthy conditions. Efficient exploitation of healthy stocks while
reducing or eliminating the capture of overfished stocks would provide industry and
management means for sustainable utilization and management of the resource.
Many members of WGFTFB have been involved in the area of research for many
years. The topic group will concentrate on behaviour and species separation in com
mercial species. A summary of the status of knowledge and future directions in re
search and application would greatly benefit FTFB members and the fishing industry.
10.3 List of Participants
Arill Engås
IMR
Norway
Kristian Zachariasssen
FFL
Faeroe Islands
Benoît Vincent
IFREMER
France
Ludvig Krag
DTUAqua
Denmark
Bent Herrmann
DTUAqua
Denmark
Mathias Paschen
BFAFI
Germany
Daniel Valentinsson
IMR
Sweden
Michael Pol
Mass. Div of Fisheries
USA
Dave Reid
FRS
Scotland
Ólafur Ingólfsson
MRI
Iceland
David Chosid
Mass. Div of Fisheries
USA
Oleg Lapshin
IMR
Russia
Eduardo Grimaldo
Univ of Tromso
Norway
Paulo Fonseca
IPIMAR
Portugal
Emma Jones
FRS
Scotland
Pingguo He
Univ of New Hamp
USA
shire
Emmon Jackson
BIM
Ireland
Rikke Petri Frandsen
DTU Aqua
Denmark
Irene Huse
IMR
Norway

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ICES WGFTFB REPORT 2008
Rosyioi Imron
Directorate of Fish
Indonesia
Jose Alio
INIA
Venezuela
Waldemar Moderhak
SFI
Poland
Abdelhak Lahnin
INRH
Morocco
Adnan Tokac
Ege University
Turkey
Altan Lök
Ege University
Turkey
Bob Van Marlen
IMARES
Netherlands
Chris Glass
Univ. of New Hamp
USA
shire
Gerard Bavouzet
IFREMER
France
Hans Polet
ILVO
Belgium
Haraldur Einarsson
MRI
Iceland
Jens Floeter
VTIOSF
Germany
Ken Arkley
SFIA
UK
Bundit Chokesanguan
SEAFDEC
Thailand
10.4 Actions
The group developed a strategy and framework for considering the terms of refer
ence in Dublin. Over the intervening year, an outline for a final report or possible co
operative research report was developed, and some text was produced. In Tórshavn,
the group further developed the report outline by subdividing into groups. The result
of this effort was the production of a timeline for completion of the overall report and
an expanded outline with responsible section leaders defined. Additional text was
also developed during the meeting.
10.5 Timetable for completion of work
· Complete draft sections and send to He or Pol by: 13 December, 2008. Re
sponsible party: section leaders
· Send to ToR a) group for and improve draft document via email. Group
members to submit comments to Section leaders by 13 February, 2009 (Re
sponsible party: All ToR a) members)
· Section leader to submit revised final draft Final draft report ready by 13
March, 2009
· Responsible party: Section leaders
· Distribute the final draft report to ToR a) members final comments and re
turn comments by 13 April, 2009 Responsible party: P. He & M. Pol
· FTFB members by: One week before FTFB in May 2009
· Verbally present at the next FTFB meeting in May 2009 (Request some time
for presentation and discussion)
· Submit to ICES for publication in Cooperative Research Report by 31 July
2009 (if there are no serious problem with the final draft)
10.6 Recommendations
1 ) WGFTFB recommends the publication of an ICES Cooperative Research
Report on Species Separation based on the work carried out by the Topic
Group.
Annex 7 gives the proposed outline of the CRR report, subject to change. Responsible
section leaders are also indicated.

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ICES WGFTFB REPORT 2008
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10.6.1 Summary of Haddock Symposium 2007 as it relates to species separation
M. Pol
Mass. Division of Marine Fisheries, 1213 Purchase St, New Bedford, MA, 02740, USA
Abstract
A symposium on haddock conservation, harvesting and management was held in
Portsmouth, New Hampshire, USA on 25­26 October 2007. Approximately 100 scien
tists, fishermen, managers and others from 5 countries attended the twoday meeting.
Twenty presentations and 11 posters were exhibited. Four talks on haddock behav
iour, including a keynote by Clem Wardle, were described. Four more papers on
avoidance of haddock were also described. Eight papers on separation of haddock in
different zones of a demersal trawl were summarized. Five papers on separation of
haddock in static gears were also summarized.
10.6.2 Can Yellowtail Flounder be harvested without bycatch of cod and haddock
on Georges Bank? Real-time spatial-temporal fishing strategies
C. Glass
University of New Hampshire, 39 College Road, Durham NH, 03824, USA
Seasonal and yearround closures of fishing grounds have been useful tools for the
Northeast Multispecies Fishery Management Plan (FMP) of the New England Fishery
Management Council (NEFMC). These closures have proven effective in improving
the status of several species covered under the FMP, and in particular, the status of
Georges Bank (GB) yellowtail flounders.
The status of GB yellowtail flounder has improved markedly since the implementa
tion of Closed Area II in 1994. The spawning stock has increased from 2600 mt in 1992
to 33,500 mt in 1999. Mean biomass has also increased from 4,500 mt to 49,600 mt in
the same time period. In 2001 the TRAC Advisory Report on Stock Status estimates
the SSB to be between 37,000 and 50,500 mt (80% probability) and the mean biomass
to be between 48,000 and 66,500 mt (80% probability). This brings the GB yellowtail
flounder biomass well above the rebuilding target of 49,000 mt.
Here we report on a cooperative research program between the fishing industry and
scientists on an observer based survey program to document the quantity and com
position of catch and discards, and assess whether the rebuilt GB yellowtail flounder
stock, within Closed Area II, can be accessed on a seasonal basis without significant
bycatch of cod and haddock.
Results from this study demonstrate that cod, haddock and yellowtail flounder show
spatial and temporal separation and that yellowtail can be harvested without a sig
nificant bycatch and discard of either cod or haddock. Furthermore, the results show
evidence of clear spatial/ecological separation between major species showing evi
dence of ecological niche separation. The results are discussed in terms of their impli
cations with regard to management of rebuilding and rebuilt stock access.
Key words: Yellowtail Flounder, Cod, Closed area, bycatch, spatial distribution.
Discussions
The author was asked how stable the patterns were between seasons. The explanation
was made that the study was conducted over three years and therefore the patterns

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ICES WGFTFB REPORT 2008
were not fully know for the longer term. It was also explained that some fishers did
not want the closed area to be opened as fishing on the borders of the closure was
economically attractive and the opening of the area caused a reduction in viability.
10.6.3 UK trials with the eliminator trawl and a new simple method for catch
comparison analysis
Andrew Revill*, Rene Holst**
*Centre for Environment Fisheries & Aquaculture Science (CEFAS), Pakefield Road, Lowest
oft, NR33 0HT, UK
**National Institute of Aquatic Resources, Technical University of Denmark (DTUAqua),
Box 101, DK9850 Hirstshals, Denmark
Abstract
This study reports on the first known trailing in European waters of a new Rhode
Island (USA) design of fishing trawl, known as the `Eliminator'. We found that this
trawl could be used to selectively harvest haddock (Melanogrammus aeglefinus) and
whiting (Merlangius merlangus) in the North Sea while allowing cod (Gadus mor
hua) and other species to escape. Catches with the Eliminator trawl were consistently
dominated by both whiting and haddock while cod numbers (of all lengths) were
reduced by 89% compared to a control trawl. Cod accounted for 2% by weight, of the
marketable fish caught in the Eliminator, contrasted by 10% in the control trawl. As
North Sea cod stocks are overexploited and at risk of being fished unsustainably, this
trawl may be a useful tool to integrate within the ongoing Northern European cod
recovery programme.
We propose a simple method based on Generalised Linear Mixed Models (GLMM) to
analyse catch comparison data and use polynomial approximations to fit the propor
tions caught in the test codend. The method provides comparison at lengths of the
two gears by a continuous curve with a realistic confidence band. We demonstrate
the versatility of the method by analysing the data from these trials, which spans a
range of species with different selective patterns.
Discussions
The author provided a demonstration of the data analysis with R routines for analys
ing catch comparison data. This was presented to interested researchers during the
meeting and will be circulated to FTFB participants.
11
ToR b): Advice to Assessment WG's
11.1 General Overview
This ToR was introduced at plenary by Dave Reid (FRS, Scotland) and a background
for the ToR was given. ICES is now asked to provide advice that is more holistic in
nature, including information on the influence and effects of human activities on the
marine ecosystem. From the fishing technology perspective this includes information
on how fishermen are responding and adapting to changes in regulatory frameworks
e.g. the introduction of effort control; technological creep; fleet adaptations to other
issues e.g. fuel prices etc. In response to this WGFTFB initiated a ToR in 2005 to col
lect data and information that was appropriate for fisheries and ecosystem based ad
vice. In 2006, the FAOICES WGFTFB was formally requested by the Advisory
Committee on Fisheries Management (ACFM) to provide such information and to

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ICES WGFTFB REPORT 2008
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submit this to the appropriate Assessment Working Group. This type of information
is becoming more and more important at both international and national levels. It
demonstrates that the community of gear technologists have an important role to
play in this and that our expertise is considered to be highly valued.
11.1.1 Terms of Reference
WGFTFB should explore the means by which it can best provide appropriate infor
mation for Assessment Working Groups and ACFM in fishery and ecosystem based
advice. This will include the information required for fisheries based forecasts, tech
nological creep and changes in fishing practices, implementation of regulations and
other fleet adaptations, ecosystem effects of fishing and potential mitigation meas
ures. All areas for which ICES provide stock advice are considered.
11.1.2 General Issues
The conveners issued a circular questionnaire to the appropriate WGFTFB members
in EU countries as well as Norway, Iceland and the Faroe Islands during February
2008 (see Annex 8). It contained a series of questions relating to recent changes within
the fleets observed and also highlighting gear/fleet/fishery related issues that are im
portant but are not currently recognised by Assessment WG's. Where possible, con
tributors were requested to quantify the information provided or state how the
information has been derived e.g. common knowledge, personal observations, dis
cussions with industry etc. For the first time in 2008 information on Mediterranean
fisheries was supplied to GFCM.
Specifically FTFB members were asked to comment under the following headings:
· Fleet Dynamics
· Technology Creep
· Technical Conservation Measures
· Ecosystem Effects
· Development of New Fisheries

Responses to the questionnaire were received from:
IMR, Norway
IMARES, Netherlands
IMR, Sweden
FRS, UK-Scotland
CEFAS, UK-England
FREMER, France
BIM, Ireland
IMR, Iceland
AZTI, Spain
FFL, Faroe Islands
ILVO, Belgium
CNR-ISMAR ­ Italy
SFIA, UK-England

The conveners worked by correspondence and met in Faroe Islands, 23--25 April dur
ing the WGFTFB meeting to collate the information provided. The full information
for individual ICES Expert Groups is given in Annex 8 but some of the general issues
raised are summarised as follows:
Fleet Dynamics
The overall picture from the questionnaires in 2008 is quite negative. Due to a combi
nation of soaring fuel prices, reduced quotas, decreasing fishing opportunities and

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ICES WGFTFB REPORT 2008
volatile prices for several key species notably nephrops, haddock, cod, monkfish and
hake, there is a general air of despondency in the fleets across Europe. There seems to
be a general trend of effort reduction across fleets and also widespread evidence of
fishermen in many countries reverting to more fuel efficient methods in an attempt to
reduce operating costs and maintain economic viability. There are also targeted de
commissioning schemes now in operation in France, Belgium, Ireland, Netherlands
and the Basque region of Spain, although it is still too early to tell what effects these
schemes will have on overall effort levels. Specific changes in fleet dynamics include
the following:
· Effort associated with French purse seine vessels targeting anchovy and
bluefin tuna has transferred to targeting red mullet, squid and whiting
with Danish Seines in the Bay of Biscay. A similar trend has been observed
in Ireland, with a switch from demersal trawling for monkfish and megrim
to Danish Seining for roundfish. It is estimated that this has increased the
Irish Seine net activity from 5 to 10 vessels in the space of one year
· French trawlers targeting whiting which traditionally operate in VIId have
switched effort into IVb due to reduced catch rates in VIId and to reduce
fuel consumption by decreasing the number of individual trips but increas
ing duration.
· The UK beam trawlers have reduced fishing activity levels due to high fuel
prices. Many are now focussing on scalloping as opposed to fish.
· There has been a shift for Scottish vessels from using 100mm110mm for
whitefish on the west coast ground (area VI) to 80mm Nephrops codends in
the North Sea (area IV). Fuel costs are a major driver, in this and all fisher
ies.
· There is a gradual shift from beam trawling on flatfish to twin trawling on
other species e.g. gurnards, and Nephrops, etc. in the Dutch fleet. A number
of beam trawlers decided to shift to other techniques such as outrigging or
flyshooting in the British Channel. Caused by TAC limitations of plaice
and sole and rising fuel costs.
· At least five large Icelandic stern trawlers have switched from single to
twin rig trawling targeting cod and haddock.
· As a result of increasing fuel prices several large Faroese DeepSea trawl
ers have plans to move to pair trawling.
· In France there have been increasing attempts to develop pot and trap fish
ing particularly in non trawling areas and deep slope and reefs.
Technology Creep
The effects of technological creep are still evident in many fisheries but the concept of
negative creep reported in 2006 and 2007 is now becoming more prevalent as vessels
try to reduce operating costs to counteract high fuel prices. Most technological creep
observed has concentrated on reducing the drag of fishing gear. Several vessels in
Iceland have begun tests with dynex rope warps instead of conventional wire warp.
The savings in drag are estimated at 20­30% although whether the potential fuel sav
ings can offset the increased costs for fitting out with dynex is unknown at this stage.
Net designs incorporating T90 netting or low drag high tenacity twines have also
been tested in a number of countries.

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ICES WGFTFB REPORT 2008
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Technical Conservation Measures
In a number of fisheries, there is some evidence of voluntary uptake of gear mitiga
tion measures. The drivers for uptake are either regulatory i.e. as a means of achiev
ing increased fishing opportunities or economic through improved fish quality. There
has also been evidence of some vessels adopting more selective gear as a way of im
proving public perception. This is particularly noticeable in the Netherlands beam
trawl fisheries. Specific examples include:
· In the Blue whiting fishery, both Icelandic and Faroese vessels are using
flexible grids with 55 mm between bars to exclude cod and saithe from
catches of blue whiting. Trials with this approach being conducted in
Norway, no uptake yet. There are predominantly large cod and saithe in
the areas where the Blue whiting is caught, thus the grid is believed to re
duce bycatch of those species by >90%.
· The Dutch beam trawl fleet is sensitive to the bad reputation of beam trawl
and this is stimulating research into selective nets and reduced bottom im
pact. Combined research activities were started in 2007, mostly catch com
parison experiments but there is an industry focus to solve this image
problem.
· Belgium beam trawlers operating in VIIg are reported to be using larger
mesh (150mm) belly panels in order to reduce retention of weed and other
benthos. Belgium fishermen's organisations are promoting the use of ben
thic drop out panels and full square mesh codends and uptake is likely to
steadily increase. One vessel is currently using these devices voluntarily
but other vessels are scheduled to adopt these modifications during 2008.
· Encouraged by access rights, Basque vessels which target mixed demersal
species in VIIIabd close to the French coast, are voluntarily using square
mesh panels to reduce discards.
· During the first Quarter of 2008 a "day at sea" in Kattegat without the grid
was counted as 2.5 days. This has further increased the incentives to use
the sorting grid to the point were 80% of all Nephrops landings in the first
quarter of 2008 were caught with sorting grids (20% previous years).
· A large number of 110mm SMPs have been bought in the first months of
2008 by the prawn fleet so that they qualify for the basic Conservation
Credits scheme. Probably affects most (~80%) of the fleet.
· Pelagic vessels in Scotland and Ireland have been fitting escape
grids/panels. These are believed to allow release of juvenile mackerel,
horse mackerel and herring. Recent trials gave equivocal results. Uptake
around 50% in Irish fleet and 10% in Scottish fleets. Possible reduced mor
tality on recruiting year classes, but no data on survival rates from escap
ing fish is available and therefore could be a source of unaccounted
mortality.
Ecosystem Effects
Evidence of discarding has been observed in a number of fisheries 2007/2008. The
motivations for discarding are a mixture of regulatory or economically driven. Spe
cific examples include:
· In Ireland there has been widespread of cod in 2007 and 2008 in ICES Ar
eas VIIbk due to early exhaustion of the cod quota.

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ICES WGFTFB REPORT 2008
· Similarly in Ireland there has been a considerable increase in the quantities
of small nephrops on the Smalls grounds in 2007 and 2008 leading to very
high landings by boats from the East coast with a high proportion of tails
to whole nephrops. There are a number of boats (up to 10 vessels) that
have participated in this fishery but do not tail due to low crew numbers
and this has lead to high discarding/upgrading.
· Potential discard problems are also reported following the introduction of
the 5% bycatch limits for spurdog on west coast and North Sea grounds.
They can be encountered in large congregations but it is almost impossible
for vessels to identify them using sonar etc so they are difficult to avoid
and are therefore caught and discarded.
· The Swedish Baltic cod trawl fishery has been concentrating effort close to
coastal areas, both due to a high abundance of fish and high fuel prices.
This costal area has been considered to be an important nursing area for
predominately juvenile cod and discarding maybe high
Ghost fishing in the deepwater fisheries in Areas IV, VI and VII remains a problem.
There are reports of discarded longlines and gill nets along the Scottish west coast
deep water grounds and in the northern North Sea.
In Iceland a number of gillnetters have shifted over to longlines as a result of pres
sures over bycatch of seabirds and small cetaceans. The level of bycatch is not known
but is felt to be quite high given the shifts in fishing method
Predation of fish catches by Grey seals from gillnet/tangle net fisheries has become an
increasing problem on the south coast of Ireland. Many inshore gillnet fishermen are
considering shifting into other fisheries as the problems have become so bad.
A number of measures have been continued to be taken by the beam trawl fleets in
Belgium and Netherlands. In Netherlands there are reports of voluntary use of longi
tudinal release holes in the lower panel of the trawl, which open when nets are filled
with benthos, and also Benthic Release Panels. Similar initiatives are ongoing in Bel
gium. In Norway, one vessel has carried out experiments using pelagic trawl doors
fished off the seabed (approx. 5 m) with a clump (weight) connected 50 m behind the
doors to ensure proper bottom contact. This method is being used to target gadoids
in the Barents Sea but with reduced seabed contact.
Development of New Fisheries
As has become the trend in recent years there are very few reports of new fisheries
being developed but a few specific examples are reported are as follows:
· A new fishery has developed in Iceland for sea cucumber. This new fishery
has not significantly removed effort from other fisheries. But after a col
lapse in the scallop stock (Breiðafjörður 2003 Chlamys islandica) some
smaller fish boats previously targeting scallops have now shifted to the cu
cumber fisheries
· Up to eight Irish pelagic vessels have continued to fish for boarfish (Capros
aper) during Q4 2007 and Q1 2008. Two vessels fished for this species in
2006 and approximately 8 vessels in 2007.
· There has been an increase by Dutch vessels in Nephrops fisheries using
twin trawls. Outrigger trawls are also replacing beam trawls, or flyshoot
ing (seining) mainly for nonquota species such as red mullet and cuttle
fish.

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ICES WGFTFB REPORT 2008
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· Squid fishery in Moray Firth continues to develop when species available
on grounds. There has been increased catches of squid reported at Rockall
in Q2 of 2008
11.1.3 Information for Individual Assessment Working Groups
Specific information relating to different areas and fisheries by Assessment Working
Groups and other Expert Groups are detailed in Annex 8. Information is provided for
the following WG's and also GFCM:
AMAWGC
WGMHSA
WGNSSK
HAWG
WGNSDS
WGNPBW
WGSSDS/WGHMM
WGECO
WGDEEP
WGMME
WGBFAS
GFCM
11.1.4 Recommendations
1 ) The topic group will continue to collate this information on an annual ba
sis, based on the issues related above and subject to further revision of the
questionnaire and better quantification of the information where possible.
2 ) WGFTFB should continue to receive feedback from the different Expert
Group's and AWAWGC, to assess the usefulness of the information sup
plied and also target specific areas that are identified of particular impor
tance to individual assessment WG's. WGFTFB are committed to assisting
in the provision of information to the new Benchmark workshops planned
for winter 2008/2009.
3 ) WGFTFB will expand the provision of information to other relevant
groups such as GFCM in the Mediterranean.
12
ToR c): Static Gear Selectivity Manual
12.1 General Overview
The ICES Static Gear manual has a history extending back to 1988 when it was first
suggested to formulate it. The current draft has described procedures for gillnet selec
tivity but procedures for longlines and pot selectivity are not well developed and this
has meant that the manual has not been completed. Given the increasing importance
of all types of static gears and particularly pots it is important that this manual is now
finished. A topic group will be formed to work by correspondence and to meet and
discuss and agreed an Action Plan timetable for completion of the Manual at the 2008
meeting of FTFB. The topic group will identify gaps in the knowledge and review
available literature pertaining to the measurement of the selectivity of all static gears.
This topic group met from the 22­24 April in Tórshavn, Faroe Islands. Nine WGFTFB
members participated and Rene Holst from Denmark held a conference call with the
Topic Group. Following their discussions the convener reported back to plenary
WGFTFB.
12.1.1 Terms of Reference
The topic group had the following ToRs:
i )
Review the current draft of the Static Gear Manual;

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ICES WGFTFB REPORT 2008
ii )
Review available literature on the measurement of selectivity of all Static
Gears and identify gaps in the knowledge; and
iii ) Agree a structure for the completion of the manual and identify a draft
ing committee to complete this task.
12.1.2 General Issues
12.1.2.1 Actions Taken
The Topic Group identified three different gillnet manuals, either complete docu
ments or draft. In addition to the draft ICES manual that dates back to 1998, there are
the following two documents:
i )
Manual on estimation of selectivity for gillnet and longline gears in
abundance surveys. Holger Hovgård (Danish Institute for Fisheries Re
search, Charlottenlund, Denmark) and Hans Lassen (International
Council for the Exploration of the Sea Copenhagen, Denmark) FAO
FISHERIES TECHNICAL PAPER 397. (2002)
ii )
Manual For Gillnet Selectivity. René Holst, Niels Madsen, Paulo
Fonseca, Thomas MothPoulsen and Aidia Campos. EU, (1997). Selectiv
ity of gillnets in the North Sea, English Channel and Bay of Biscay.
AIR2­93­1122. 61 pp + Appendices.
As a first step the Group considered these three manuals of existing static gear selec
tivity manuals and identified the strengths, weaknesses and gaps in knowledge.
None of the manuals were considered a "finished" document and the statistical
analysis in all three needed to be updated. There was very little information on other
static gears such as longlines and pots and any of the analysis included seemed less
than robust.
12.1.2.2 Agreed Plan for Completion of manual
Having considered the relevant documentation the Group agreed a plan for comple
tion of the ICES manual. The ICES document was felt to be 80% complete but on the
basis of the information available it was felt pertinent to restrict the manual to static
nets only i.e. gillnets, trammel nets and tangle nets. This was not seen as a major issue
as the measurement of selectivity of longlines and pots is a developing science. It was
also identified that a lot of the relevant information needed to complete the manual
was contained in the EU project but it would be necessary to write to the EU for per
mission to use and update this information so as not to breach copyright laws.
With regard to the overall content of the manual the main issues identified were as
follows:
i )
The original text needs some editing to improve the grammar.
ii )
The Statistical methods need updating.
iii ) The boundaries and applicability of the manual need to be detailed i.e.
the methods should not be used for species where the selectivity is not
well defined (fish with spikes).
iv ) Graphics and diagrams are required.
v )
It would be very useful to add case studies, documenting relevant ex
periments and analysis carried out.
vi ) The finished document will need to be peer reviewed before publication.

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ICES WGFTFB REPORT 2008
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12.1.2.3 Provisional timetable for completion of work
The Topic Group outlined a provisional timetable for completion of the manual as
follows:
· May (Chair FTFB) ­ Contact EU (permission)
· MayJuly (Italy and Belgium) ­ review recent literature for any new issues,
methods (i.e. paint etc).
· Italy will consolidate findings and advise UK and Denmark
· July ­ Italy to supply UK with Italian case study
· July ­ France to supply graphics to UK
· July ­ Italy to search for suitable case study involving hanging ratios (if not
found use Danish case study on twine diameter)
· July Sept ­ Denmark to update statistics and incorporate case studies
· July Sept UK to draft final report and distribute to Italy, Denmark,
France, Belgium
· Oct ­ France, Belgium and Denmark to return draft with comments
· Nov ­ UK to amend report and be offered to FAO for external review
· Dec ­ Review complete(subject to offer being accepted by FAO)
· 2009 ­ Consider the possibility of a joint FAO/ICES publication noting that
issues of publication coats and copyright ownership need to be discussed.
This was presented and agreed at plenary as the best way forward, although there
were some reservations about not including longlines and pots in the manual but
given the information is incomplete and to include this would be a major task that in
the opinion of the Topic Group could not be completed in a reasonable timeframe.
12.1.3 List of Participants
Andy Revill
CEFAS
UK
Gianna Fabi
ISMARCNR
Italy
Fabio Grati
ISMARCNR
Italy
Jacques Sacchi
IFREMER
France
Dirk Verhaeghe
ILVO
Belgium
Kris van Creaynest
ILVO
Belgium
Peter Munro
NOAA
Alaska
Frank Chopin
FAO
Italy
Jonathen Dickson
FAR
Philippines
Rene Holst
DTUAqua
Denmark (by phone)
12.1.4 Recommendations
1 ) WGFTFB recommend that the Topic Group work to the timetable outlined
to produce the manual. This will be presented to WGFTFB at the 2009
meeting.
12.2 Individual Presentation
12.2.1 Size selectivity of basket traps for the gastropod Nassarius mutabilis in the
Adriatic Sea
Gianna Fabi and Fabio Grati

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ICES WGFTFB REPORT 2008
Istituto di Scienze Marine ­ CNR, L.go Fiera della Pesca, 260125 Ancona, Italy
Abstract
Fishing of Nassarius mutabilis is performed along the coast of the central and northern
Adriatic Sea from autumn to spring by smallscale vessels using basket traps with a
19mm mesh size. This fishery usually gives higher income than any other set gear,
but in the last years landings have shown a general decrease. Management measures
such as Minimum Landing Size (shell height = 20 mm) and mesh opening of the sieve
used to sort individuals larger than MLS are currently enforced. Nevertheless, large
amounts of small specimens are commonly caught and sold.
In order to avoid the catch of undersized individuals, the selectivity of basket traps
was evaluated in a comparative study. Three experimental nets (colour white; mesh
openings 23, 26, 28mm) were fished in conjunction with two commercial nets (mesh
opening 19mm) of different colours (black and white) and one control net (colour
white; mesh opening 5mm). One hundred and twenty traps were randomly ar
ranged in one set deployed on a muddy bottom (10 m depth) and hauled five times in
September 2004. According to commercial fishing practice, traps were baited with
horse mackerel and soak time was 24 hours. Size selectivity was estimated with the
SELECT method commonly adopted for trouser trawl experiments using CC2000
software (Constat, 2000).
Selectivity parameters were estimated for a pool of curves, but the logistic model
gave the best results. Goodness of fit test based on model deviance gave high p
values in all cases, being the lowest one 0.74 for the 19mm trap (black).
H50 increased from 15.9 mm for the white 19mm trap up to 24.1 mm for the 28mm
one. Around 3,000 specimens were caught with the control traps, 988 with the black
19mm traps, 576 with the white 19mm traps, 263 with the 23mm traps, 114 with the
26mm traps and 7 with the 28mm ones. Percentage of individuals larger than MLS
gradually increased from 14% in the control 5mm traps up to 100% in the 26mm and
28mm ones. Comparison between black and white 19mm traps did not show any
significant difference, both in terms of L50 and of catch yields. These results indicated
that the 19mm mesh commonly used by fishermen is not adequate to sustainably
exploit N. mutabilis due to the large amount of undersized specimens in catches,
while the 23mm mesh represented a good compromise between commercial fishing
yields and protection of undersize animals.
Discussion
The author was asked how the small Nassarius were thought to be escaping from the
pots but the author could not provide any explanation. It was stated that in a Cana
dian study no improvement in mesh size selectivity could be achieved for whelk pots
where the catch sizes were very high and the species exhibited similar behaviour. It
was explained that in the present study catch for 500 pots were only about 100 kg and
this relatively low catch rates was felt to be the likely cause of difference in the selec
tivity achieved. The question was asked as to whether the escapees survived but this
was unknown and the main reason for trying to increase selectivity was a motivation
to increase efficiency through reduced sorting times.

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ICES WGFTFB REPORT 2008
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13
ToR (d) Mitigation Technologies for Protected Species
13.1 General Overview
This ToR was proposed by Alessandro Lucchetti and Antonello Sala of CNRISMAR
at the WGFTFB meeting in Dublin 2007. The group worked by correspondence dur
ing 2007/2008 and met at FTFB in 2008 in Tórshavn, Faroe Islands. An overview of
this topic and a paper on `Turtle Excluder Devices Experiments in the Central Adri
atic Sea' were presented at plenary by Alessandro Lucchetti.
13.1.1 Terms of Reference
The Topic Group addressed the following ToRs:
· Identify fisheries where technical mitigation measures have been intro
duced to reduce the bycatch of protected species; and
· Review the efficacy of these technical mitigation measures introduced to
reduce the bycatch of protected species such as small cetaceans or turtles.
13.1.2 Identification of technical mitigation measures
Prior to WGFTFB, the ICES Study Group for Bycatch of Portected Species (SGBYC)
had produced a "Compendium of Mitigation Methods deployed to minimise bycatch
of protected species" at their meeting in January 2008 (See Section 3.6). This table was
considered by the WGFTFB Topic Group and additional information incorporated
from FTFB members, including the participants from FAO REBYC (Reduction of By
cacth in Tropical Shrimp Trawling) project. The group also tried to identify technical
or practical difficulties associated with mitigation measures which were deemed ex
perimental by SGBYC.
Based on the information gathered by the Topic Group, the table was revised accord
ingly as shown in Annex 9. Table 6 below summarises the entries broken down into
measures currently legislated for, being used voluntarily or purely experimental by
broad species categories as follows:
· Small Cetaceans
· Whales
· Pinipeds
· Sea Turtles
· Seabirds
· Other large fish species such as sharks and rays

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ICES WGFTFB REPORT 2008
Table 6. Summary table of mitigation measure by species.
SPECIES CATEGORY
LEGISLATION
VOLUNTARY USE
EXPERIMENTAL
Small Cetaceans
4
4
15
Whales

3
2
Pinnipeds
2

6
Sea Turtles
13

9
Seabirds
2
3
5
Other Large Fish
5

3
Species
It was agreed that this table was extremely informative and accordingly should b be
circulated to all WGFTFB members for further updating. The updated version would
then be forwarded to SGBYC And other relevant Expert Groups.
The Topic Group also considered the specific case of loggerhead turtle bycatch in
Mediterranean fisheries on the basis of a study presented by Alessandro Lucchetti.
The full case study is presented in Annex 10. Data on the level of bycatch of protected
species in the Mediterranean is extremely sporadic but given the number of fisheries
with potential impacts the levels are undoubtedly significant. The specific case study
presented cites estimates of more than 60,000 turtles caught annually in trawl,
longline and static gear fisheries with mortality rates of individuals caught ranging
from 10­50%. The actual catches are anticipated to be far higher given that many
countries do not report any bycatch. The report details research carried out with dif
ferent mitigation measures for trawls and longlines and recommends the need for
further research and enhanced data collection programmes to provide a better under
standing of the scale of the problem. The use of TEDS, modified to match the catch
composition in Mediterranean bottom trawl fisheries, as well as simple gear modifi
cations in longline fisheries such as using mackerel instead of squid, deeper setting
and the use of circle hooks are recommended for further investigation, given they are
proven mitigation technologies in other parts of the world.
13.1.3 Assessment of efficacy of the technical measures
The Topic Group considered the response by SGBYC to the following TOR:
"Review of methods and technologies that have been used to minimise bycatch of species of
interest, including methods that have failed".
This report identified that in a number of fisheries, mitigation measures to reduce
bycatch of protected species (cetaceans, pinnipeds, turtles and large fish species) had
been introduced (e.g. new type of hooks, TEDS, acoustic deterrents etc.) and in some
cases there was evidence that bycatch had been reduced, but little or no attempts had
been made to quantify this reduction.
The ToR addressed by SGBYC was seen by WGFTFB as a precursor to the work to be
completed in attempting to develop a framework for such an assessment. The Topic
Group considered the report by SGBYC and concluded that it was very comprehen
sive and had identified all elements that should be addressed when introducing miti
gation measures for minimise protected species bycatch.
The Topic Group then considered the findings in the context of the methodology
used by WGFTFB in reviewing the efficacy of recent (2003) technical measures intro
duced into the North Sea C. crangon fishery (Sieve nets / grids) aimed at reducing dis

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ICES WGFTFB REPORT 2008
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carding of juvenile whitefish (ICES, 2007). This assessment considered social, biologi
cal and economic factors along with technical issues in the design and use of the
technical measure.
The Topic Group attempted to apply this methodology to the case study on logger
head turtle bycatch in Mediterranean fisheries to determine whether it was possible
to assess the efficacy of potential measures that could be used in these fisheries. It
was concluded, however, that given only limited information was available it was not
possible to carry out the assessment. The Topic Group considered more established
mitigation technologies such as acoustic deterrent devices into gillnet fisheries and
the use of TEDS in shrimp trawl fisheries but the data required on levels of bycatch,
uptake of the devices and the potential impact of the measures on the protected spe
cies stock are not at a current level of resolution to allow an assessment to be made. It
was felt unlikely that in the short term that such an analysis would be possible for
any mitigation measure for the reduction of bycatch of protected species.
13.1.4 List of Participants
Alessandro Lucchetti
ISMARCNR
Italy
Dominic Rihan
BIM
Ireland
Håkan Vesterberg
Swedish Board of Fisheries
Sweden
Huseyin Ozbilgin
Mersin University
Turkey
Sven Gunnar Lunneryl
Swedish Board of Fisheries
Sweden
Pascal Larnaud
IFREMER
France
13.1.5 Conclusions
1 ) WGFTFB acknowledges the work carried out by ICES SGBYC in develop
ing the table of mitigation measures and has sought to update this table.
2 ) WGFTFB concludes that the impact of fisheries on Loggerhead turtle
needs to be considered urgently given the scale of the problem. Research
into the applicability of proven mitigation technologies to reduce the by
catch should be supported.
3 ) WGFTFB have been unable to use the methodology developed in 2008 to
assess the efficacy of mitigation measures for protected species. WGFTFB
conclude that this methodology is data dependent and for most protected
species bycatch issues such data does not exist currently.
13.1.6 Recommendations
1 ) WGFTFB recommend that the Compendium of Mitigation Methods de
ployed to minimise bycatch of protected species developed by SGBYC and
expanded on by WGFTFB should continued to be updated as information
on work being undertaken globally becomes available.
2 ) WGFTFB recommend that GFCM encourage Mediterranean States insti
gate data collection programmes to provide a better understanding of the
bycatch issues in Mediterranean fisheries, particularly in nonEU countries.
3 ) WGFTFB recommend that research in the Mediterranean on mitigation
technologies be carried out under commercial conditions and include con
sideration of socioeconomic effects of introducing such technologies.
4 ) WGFTFB recommend as a matter of priority that GFCM instigate further
development and testing of Turtle Excluder Devices in trawl fisheries in

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ICES WGFTFB REPORT 2008
the Central Adriatic, Tunisia and the Northeast Mediterranean given the
level of turtle bycatch in these areas.
5 ) WGFTFB recommend that GFCM instigate research and pilot projects to
ascertain whether simple modifications to longline gears such as the use of
circle hooks, different bait types and setting depths used extensively in
other parts of the world e.g. US and Hawaii to reduce turtle bycatch are
appropriate in the Mediterranean.
13.2 Individual Presentations
13.2.1 Turtle Excluder Devices Experiments in the Central Adriatic Sea
Alessandro Lucchetti, Antonello Sala, Marco Affronte
CNR, Italy
Abstract
There are three turtle species in the Mediterranean Sea: the leatherback (Dermochelys
coriacea), the green (Chelonia midas) and the loggerhead turtle (Caretta caretta). Logger
head sea turtles are listed as endangered in the Red List of Threatened Species of the
International Union for Conservation of Nature and Natural Resources (IUCN). In
the Mediterranean Sea, they represent the most abundant species of marine turtles.
The CentralNorthern Adriatic Sea, for its shallow waters (<100 m) and rich benthic
communities is considered one of the most important foraging areas in the whole
Mediterranean area for the loggerhead turtle population during the demersal phase
of their life cycle.
In the Mediterranean Sea, turtles are usually threatened by longline and driftnet
fleets, very often used illegally. Nevertheless, in the CentralNorthern Adriatic Sea a
growing number of sea turtles are accidentally caught by bottom trawlers in the last
number of years. Few unofficial observations report that most of the incidental
catches occur in late winter and spring in coastal areas. Incidental catch probably oc
cur during towing operations when turtles are foraging on the bottom. It is estimated
that in this area more than 4000 turtles per year are caught by trawls. One of the most
important gear modifications used globally to protect sea turtle, especially the juve
nile and subadult size classes, is the use of Turtle Excluder Devices (TEDs). TEDs
actually represent a management measure widely employed in several areas of the
World but no specific testing in Italian waters is recorded.
There are a variety of hard TED designs available for fishermen but generally it is
very difficult to introduce new technical solutions, taking into account that innova
tions can be easily accepted only if economic losses in terms of marketable fish
catches are insignificant. During the LIFE project TARTANET, we projected and
tested at sea five different TEDs with the aim of finding the best way mitigation tech
nologies for Italian waters. The first two TEDs tested at sea were a simple oval grid
type, made of aluminium and plastic respectively. They were not satisfactory because
of the losses of many commercial species and therefore they were felt not commer
cially acceptable in the short term.
Two other experimental lowcost and semirigid grids (TARTEDs), similar in shape
but made first in plastic and then in a composite rubbermaterial, were tested. They
were a fixedangle TED with a single hoop used to strengthen the TED frame and to
maintain TED angle. The hoop and the deflector grid were sewn to the trawl exten

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ICES WGFTFB REPORT 2008
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sion in order to fix the angle of the TED in the trawl. In fact the angle at which the
TED operated during towing (30° to 55° from the horizontal) is an important factor in
preventing fish loss.
Both the TARTEDs were very efficient because they allowed the release of large
quantities of debris (plastic materials, wood, stones, etc). This characteristic positively
affected the fish quality of the commercial catch portion. Moreover, the losses of
commercial species were insignificant in most tows. In order to evaluate the effec
tiveness of the TARTEDs in releasing turtleshape bodies, some tests were performed
using a simulate "turtle" using a container 40X40 cm deployed along the towing di
rection. All tests showed positive results and all the waste materials included the con
tainer and even a carapace of a dead turtle was released from the turtle escape
opening.
Finally, comparative sea trials were carried out, testing a traditional Super Shooter
TED and the semirigid TARTED. Fishermen were very interested in testing this
technical solution especially as debris separation grid. During winter they usually
exploit typical fishing grounds of the Central Adriatic Sea, characterized by a great
amount of sea cucumbers (Holothuroidea). These areas, which represent an impor
tant habitat for several commercial species, are actually overexploited by trawlers
and the use of TEDs should avoid the catch and the death of sea cucumbers allowing
the protection of this typical fishing grounds.
In conclusion, the two lowcost TARTEDs, compared to the Super shooter TED, were
easier to rig and they seem to be more efficient in releasing debris with insignificant
economic losses, furthermore the characteristics of the materials of the semirigid
TARTEDs make the handling easier during hauling. The simulation experiments
suggest they are also effective at realising turtles from trawls.
Discussion
The scale of the problem in the Mediterranean as presented was commented on by a
number of participants and the importance of the need to develop mitigation tech
nologies for all gear methods was emphasised. Experiences with longline fisheries in
the US were highlighted including the use of circle hooks and deep setting of longli
nes. These methods while useful are not 100% reliable.
14
ToR e): Request form WGEF
See section 3.1.1.
15
ToR f): Ad hoc Topic Group on Shrimp Trawl Efficiency
15.1 Request
In the NIPAG report of 2006 the following recommendation was made:
"During the NIPAG assessments in 2006 there was a discussion of the use of double
trawls in the shrimp fishery and how best to represent the effort of these trawls. They
may not exert twice the effort as a single trawl. STACREC noted the importance of this
issue and encouraged Contracting Parties to study the efficiency of twin shrimp trawls.
STACREC noted that for bottom trawls one factor in standardizing effort is to count
the number of meshes in the circumference of the trawl opening. Given the importance
of estimates of effort to shrimp assessments STACREC recommended that the appropri

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ICES WGFTFB REPORT 2008
ate method to estimate effort from twin trawls (bottom and midwater) be referred to the
ICES Fishing Technology Working Group".
STACREC (June 2007:80) and the Scientific Council of the NAFO/ICES Pandaleus As
sessment Group (OctoberNovember 2007:218) responded to the request of the NI
PAG (SCS 06/27, p. 47) to forward the question of the efficiency of single and double
trawls to the April 2008 meeting of the ICES/FAO WGFTFB. The request received was
as follows:
"During deliberations of various shrimp stocks it was noted that twin trawls, and in
some cases triple trawls, were being utilized for the improvement of catch quality
rather than catch rate. It was pointed out that the physical attributes of some twin
trawls (e.g. the number of meshes in the circumference) may not be too different from
single trawls. NIPAG considered that further investigations should be conducted to
address this as it is could be very informative in interpreting standardized catch rate
indices. This would include investigations of the use of twin and triple trawls in
other fisheries as well, for example Greenland halibut directed fisheries, where their
deployment may be used to improve catch rate rather than catch quality".
This request was forwarded to ICESFAO WGFTFB in 2007. WGFTFB has addressed
this request by soliciting input from a number of specific experts with information
and/or comments received from Iceland, Canada, Norway, Faroe Islands and UK
Scotland. The Chair of WGFTFB has taken this information and produced this docu
ment as an attempt at addressing the specific request and the findings and recom
mendations were agreed at the WGFTFB meeting in April 2008 in the Faroes Islands.
It should be noted that the views expressed do not necessarily reflect fully the views
of all the contributors.
15.2 Shrimp Trawl Evolution
The fishery for Pandalus shrimp has been in existence for a large number of years
beginning in Iceland in the 1930's in inshore waters, and moving to the offshore fish
eries in the 1970's. The trawls used have increased in size from simple two panel
trawls to large four panel nets fished as twin or even triple rigs, designed to take ac
count of diurnal variations in shrimp behaviour. In the past 20 years or so, stronger
netting materials have been introduced, vessels have shifted from steel bobbins to
rubber rockhoppers and in general, the trawl design has undergone considerably re
finement to maximise efficiency.
In 1991, after a visit to the Danish fisheries, an Icelandic Nephrops skipper succeeded
with towing two trawls simultaneously, increasing the shrimp catch significantly. In
1993, an Icelandic factory trawler, `Sunna SI' managed to fish with two shrimp trawls.
In her first trip, she had to go ashore for more crew to cope with the increased
catches. Since then, most large shrimp trawlers have changed to twin trawling. In
Norway, the first vessels using twin trawls entered the fishery in 1996. Since then,
efficiency has increased continuously, and in 2002 approximately 35 Norwegian ves
sels had the technology to use double or even triple trawls. Since 2002, the majority of
the yield is taken by twin trawl.
Modern shrimp trawls are characterised by having wider horizontal spreads than
traditional trawls of a similar size. This is largely to maximise swept area of the
groundgear and also allows towing in areas of rough ground without damage to the
trawl. There are also specially designed trawls with high vertical openings shrimp
trawls suitable for night fishing in areas where shrimp are lifting off the bottom. 2 d 3

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ICES WGFTFB REPORT 2008
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15.3 General Comments
It is important in the first instance to point out that all shrimp species like Pandalus
borealis are captured by a pure filtering process. Therefore, the area swept by the
small meshes (< 50mm) is what determines the capture efficiency. Horizontal opening
is thus more important than filtered volume with respect to catch volumes. Wingend
spread is more important for shrimp trawl efficiency than a high vertical opening and
consequently using circumference of the trawl is not a particularly accurate measure
of efficiency for shrimp trawls.
Given the fundamental differences in the catching process, comparisons between sin
gle and twin trawls for fish species and shrimp is not considered by WGFTFB to be
very relevant as herding efficiency by sweeps can very much influence the capture
efficiency of fish. Long sweeps in a single trawl rigging can compensate for twin
trawls for many fish species but not necessarily for shrimp. The overarching conclu
sion is that if the same size of trawl is used as a single or twin trawl, the twin trawler
will almost double the catch although there is evidence of single trawlers having the
same towing power as a twin rig vessel often increases the trawl size including the
fishing line length, and can catch more than half of the twin trawler. Measurements in
Canada showed in comparison with a single trawl, by using the twin trawl method
the swept volume increased from 106m² to 193m² an increase of 82%. Swept area in
creased from 1,739m² to 2,067m², an increase of 19%.
The relationship between wingend spread and shrimp catch is further borne out by a
study carried out in Newfoundland (DeLouche et al., 2005). This study provided
valuable information on shrimp distribution and size in the bottom waters. It also
raised questions as to the trawl gear designs that are currently being used commer
cially to harvest northern shrimp. The results from this work clearly demonstrated
that the upper 1/3 of the typical trawl that is used to harvest shrimp is not an effective
harvesting tool. In this study it was found imperative that 100% of the swept area of
the trawl be actively catching shrimp. Based on the findings of this report any trawl
design must have a reduced vertical opening and a higher horizontal spread. Essen
tially trawl design should look at maintaining mouth area by reducing the vertical
opening of the trawl and increasing the wingspread. By doing this the trawl will now
be targeting shrimp where they are known to exist in high densities. With this design
it is possible that more energy may required to tow the trawl, thereby burning more
fuel, but fishing trips may be reduced by several tows as well, thereby saving on fuel.
In Norwegian shrimp fisheries there is a tendency towards increasing the fishing line
length and to use larger meshes in the upper panels. Among the larger shrimp vessels
there are no single trawlers left although in the coastal shrimp fisheries some vessels
are still operating a single trawl. There are currently three Norwegian trawlers are
presently operating three trawls.
15.4 Icelandic Effort Data
Having said that shrimp trawl efficiency is related more to wingend spread than ver
tical opening, there are no analysis known to WGFTFB that have attempted to assess
relative efficiency of single and twin rig trawls for any species, including shrimp us
ing this parameter. Thus the only reliable estimate of single vs. twin rig efficiency is
based on Icelandic data.
By extracting data from logbooks, MRI in Iceland have compared catches h1 from all
single and double rig hauls taken with 2400 ­ 3600 mesh circumferences trawls from

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ICES WGFTFB REPORT 2008
1994 to 2000 in Icelandic waters. The catches are standardized for 3000 mesh trawl,
i.e.
Standardised catch h1 = catch × 3000 × h1 × (actual trawl circumference)1
Comparing the mean catch rates for every year from single trawl hauls with those
from double trawls, average catch rates for twin trawls of 1.25 ­ 2.24 times that of a
single trawl, with an average of 1.66 were found in this analysis. The betweenyear
variations cannot be explained, but perhaps a more detailed analysis, taking into ac
count time of year, area, vessel size etc. would reveal the reasons for these differ
ences.
Table 7. Mean catches and number of vessels fishing with 2400 ­ 3600 mesh circumference trawls,
single and double rig, from 1994 ­ 2000 in Icelandic waters.
Year
1994 1995 1996 1997 1998 1999 2000
No. vessels with double rig
1
2
1
4
6
8
2
No. vessels with single rig
24
29
22
38
37
37
32
No. hauls with double rig
420
708
115
405
1168
705
208
No. hauls with single rig
7373
6927
6067
11377
9319
7542
8052
Mean shrimp catch h1 :Double
665.9
590.1
571.8
513.5
443.2
194.8
235.8
Mean shrimp catch h1 :Single
297.3
308.8
367.5
354.5
228.7
156
178.9
Catch rate: double / single
2.24
1.91
1.56
1.44
1.94
1.25
1.32
A further comparison was carried out by MRI, Iceland for twin and single rig gears in
the Flemish Cap fisheries in March October for the period 1994 to 1999. Catches of
Icelandic vessels from 4513 hauls with twin rig and 5334 with single rig were stan
dardized to catch/h pr. 3000 mesh circumference calculated as 40mm mesh size
(which was about the average size of the trawls). Overall catch ratio twin rig: single
rig was found to be 1.90, st.dev = 0.30. There were seasonal variations in the catch
ratio, from ~2 in March ­ May, to 1.5 ­ 1.7 in September ­ October (ratio = 2.465
0.0816 × month, p< 0.005, 3 month 10). See Table 8 below.

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ICES WGFTFB REPORT 2008
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Table 8 Comparison of cpue of single trawls and double trawls by month over a period of six
years. The area is the NW area (No. 3) of Flemish Cap. Kg/hr is standardised to a trawl size of 3000
meshes (40mm mesh size), i.e. estimated headline height of 13­14m.

15.5 Catch Quality versus Catch Rate
WGFTFB could find no evidence of multiple rigs being used to improve catch quality.
The sole motivation for using multiple rigs (twin or triple rigs) would appear solely
catch efficiency due to increased horizontal spread. The main tool that has improved
catch quality is the use of the Nordmore grid, which gives cleaner shrimp catches.
There is evidence, however, of fishermen using so called twin or trouser codends in a
number of fisheries including the Pandalus shrimp fishery. These include:
· UK Distant water cod fishery in Iceland and Greenland
· South African Hake fishery
· UK Scottish and Irish Nephrops fisheries
The motivation for using trouser codends, which in Canada are seen as an alternative
to twinrigs, are considered threefold:

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ICES WGFTFB REPORT 2008
· Reducing the risk or impact of gear damage on catches by splitting the
catch;
· Increased wingend spread due to the increase in width of the trawl needed
to accommodate the additional codend; and
· Catch quality due to a splitting of the catch.
Compared to a single trawl of a given size, a twin codend can achieve a 20% increase
in footrope spread. Experimentation with three codends has indicated that it is possi
ble to increase this to 47% compared to a single trawl. It is also important to note that
in trouser codend trawls the footrope swept area increase is concentrated in the mid
dle section of the net, not in the wings. The wider centre area is a major advantage
when targeting shrimp.
15.6 List of Participants
Dominic Rihan
BIM
Ireland
Haraldur Einarsson
MRI
Iceland
John Willy Valdemarsen
IMR
Norway
Dick Ferro
FRS
UKScotland
Olafur Ingolfsson
MRI
Iceland
Harald DeLouche
MI
Newfoundland
Kristain Zachariassen
FFL
Faroe Islands
15.7 Conclusions
1 ) WGFTFB concludes that due to the catching process for shrimp, horizontal
opening is more important than filtered volume with respect to catch vol
umes and this is reflected in the current trends in shrimp trawl design.
2 ) WGFTFB concludes that due to the fundamental differences in the catching
process, comparisons between single and twin trawls for fish species and
shrimp are not relevant as herding efficiency by sweeps can very much in
fluence the capture efficiency for fish.
3 ) WGFTFB can find no reliable estimates of single vs. twin trawl efficiency
based on horizontal spread. Icelandic effort data using trawl circumference
shows average catch rates for twin trawls of between 1.25 2.24 times that
of a single trawl, with an average of 1.66.
4 ) WGFTFB can find no evidence of multiple rigs being used to improve
catch quality. The main tool used that does improve catch quality is the
Nordmore sorting grid. There is evidence, however, of fishermen using
twin or trouser codends to reduce the risk of gear damage, increase win
gend spread and improve catch quality.
15.8 Recommendations
1 ) WGFTFB recommends the issue of shrimp trawl efficiency be addressed to
SGGEM as a case study for consideration
2 ) WGFTFB recommends further analysis of the Icelandic or other suitable
datasets by SGGEM.
3 ) WGFTFB recommends that SGGEM should consider whether horizontal
wingend spread can be used as an effort parameter for this fishery.

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ICES WGFTFB REPORT 2008
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16
ToR g): WGECO request as part of the OSPAR QSR 2010
16.1 General Overview
With increasing public and political concerns on marine fisheries and environmental
issues, fisheries science and management has become increasingly complex. The
move to the ecosystem based approach to Fisheries Management has gained momen
tum as the multiple uses of marine resources have broadened to take account of eco
system considerations and the recommendations from the numerous international
agreements, conferences and summits held on the subject. Some of the most impor
tant of these include:
· The 1972 World Conference on Human Environment.
· The 1982 United Nations Law of the Sea Convention.
· The 1992 United Nations Conference on Environment and Development
and its Agenda 21.
· The 1992 Convention on Biological Diversity.
· The 1992 Habitats Directive
· The 1995 United Nations Fish Stocks Agreement.
· The 1995 FAO Code of Conduct for Responsible Fisheries.
· The 2001 Reykjavik Declaration.
· The 2002 World Summit on Sustainable Development.
· The 2002 Green Paper of the European Commission
· UN 2006 General Assembly to ensure protection of vulnerable marine eco
systems
· The 2007 Committee on Fisheries of the UN FAO on IUU and protecting
the marine environment
· The 2007 Integrated Maritime Policy for the European Union
ICES is in the process of restructuring its Science and Advisory processes and is col
laborating with HELCOM and OSPAR, among others, in the evolution of a holistic
ecosystembased approach to fisheries management. WGFTFB have been discussing
the subject of fishing impacts for a number of years and has addressed it as a specific
ToR in 2004 (ICES, 2004). Much of this though has been in isolation with limited dia
logue between other EG's including WGECO. WGFTFB has recognised this and has
discussed internally the need to define its new research direction, beyond the tradi
tional focus of bycatch reduction, into developing environmentally responsible fisher
ies (ERF) in support of the ecosystem approach to fisheries management. The
stimulus for these discussions were prompted by the ever increasing international
calls for ban on bottom trawling on high seas' and also debate at the 2006 ICES Sym
posium on Fishing Technology in the 21st Century: Integrating Fishing and Ecosys
tem Conservation held in Boston (Glass et al., 2007). Since WGFTFB works closely
with and has industry people as part of their membership it felt that it should be
16.1.1 Terms of Reference
Recognizing the need for better integration between WGFTFB and WGECO, at last
year's FTFB meeting in Dublin (ICES, 2007) an ad hoc group made a first attempt to
address this and explore ways of enhancing links with other ICES WG's. WGFTFB
also addressed a joint ToR with WGECO on the impacts of Crangon beam trawl fish

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ICES WGFTFB REPORT 2008
eries in the North Sea in 2007. Later in 2007 at the ICES ASC in Helsinki a ToR was
formulated between the Chairs of WGFTFB and WGECO as follows:
"For each OSPAR region, select and succinctly describe one or more representative
examples of gear modifications, which have resulted in changes to the ecosystem ef
fects of these gears, including if possible a range of ecosystem components."
The work contributes to WGECO ToR b) which will pull together an environmental
assessment of the impact of fisheries, in preparation for the OSPAR QSR. It is also
seen as means to begin the wider debate on how to properly assess the effect and im
pact of gear based measures through the development of a proper assessment
framework. This will be worked on at WGECO in 2009.
16.1.2 General Issues
To address the specific TOR, a Topic Group was convened and worked by corre
spondence prior to WGFTFB. Representative case studies were identified by the
Topic Group to illustrate the positive and negative impacts of different gear based
technical measures. The identified cases studies were first introduced at plenary and
then the Topic Group convened to draft the documents. These were then presented at
plenary and recommendations agreed. The case studies identified are as shown in
Table 9 below.
Table 9. Case studies, identified for the description of representative examples of gear modifica
tions that are designed and selected for the mitigations of ecosystem effects.
Case
Fishing gear
Target species
OSPAR-region
Ecosystem
study
component
1 (IRL)
Gill net
Mixed demersal
OSPARRegion II,
Marine mammals
III & IV
2 (Eng)
Demersal otter
Norway lobster
OSPARregion II
Fish species
trawl
(Nephrops
norvegicus)
3 (B,
Flatfish beam trawl
Mixed, demersal
OSPARregions II,
Fish species
NL, UK)
fish species, mainly
III, IV
Benthic invertebrate
sole (Solea solea) and
species
plaice (Pleuronectes
platessa)
4 (B,
Shrimp beam trawl
Brown shrimp
OSPARregion II
Mainly commercial
DK, F,
(Crangon crangon.)
fish species
GER,
NL, UK)
5 (Faroe
Pelagic otter trawl
Blue whiting
OSPARregion I &
Fish species
islands)
(Micromesistius
V
poutassou)
The case studies are presented in full in Annex 11. They are written in the following
format:
i )
Brief overview of the situation prior to mitigation measures/regulation.
ii )
The drivers that initiated gear measures being developed or introduced.
iii ) A description of what was done in terms of mitigation measures.

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ICES WGFTFB REPORT 2008
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iv ) A description of what management measures were taken after the re
search i.e. was the mitigation measure introduced into regulation or was
it only tested and then used or not used voluntarily
v )
A description of how the impacts of the gear modifications have been
assessed.
vi ) A description of how successful this has been in terms of reducing im
pacts.
16.1.2.1 List of Participants
Jochen Depestele
ILVO
Belgium
Dominic Rihan
BIM
Ireland
Tom Catchpole
CEFAS
UK
Kristain Zacchariassen
FFI
Faroe Islands
Phil MacMullen
SFIA
UK (Parttime)
Andy Revill
CEFAS
UK (Parttime)
Dick Ferro
FRS
UKScotland (by correspondence)
Barry O'Neill
FRS
UKScotland (by correspondence)
16.1.3 Conclusions
The integration of fishing gear technology research in the framework for fisheries
management is a prerequisite for achieving an ecosystembased approach. It is rec
ommended that many of the issues evolving from the selected case studies should be
taken into account in a framework for assessing impacts and management measures
related to fishing gear based technical measures.
Fishing gear technologists tend to focus on single or multiple commercial fish species.
With the exception of charismatic species, very little fishing gear research is focused
on nontarget fish species and benthic invertebrates; although such gear modifica
tions might have an effect on nontarget fish and invertebrate species. Most of the
fishing gear research is driven by the fisheries management objectives, which is in its
turn mainly driven by the healthiness of commercial fish stocks. There is gradually a
focus on a more ecosystembased approach, but very few fishing gear research is yet
focusing on other ecosystem components. Therefore there is need to consider biologi
cal and ecological impacts of gear measures during the research phase and before
inception into legislation.
Fisheries gear research has and is focusing on the reduction of physical habitat im
pacts (e.g. EUproject "DEGREE"), but few of these efforts have been implemented in
the actual fisheries and this is reflected in the fact that the authors could not identify a
good case study to address this.
Research on gear modifications to improve selectivity of commercial fish species
through a variety of sorting devices has been proven to reduce bycatch and discards
rates, mainly of fish species (Valdemarsen and Suuronen, 2003, Suuronen and Sarda,
2008). The application of these gear modifications can be achieved through regula
tions or sometimes through the voluntary use by fishermen. Regulatory and market
incentives both can lead to an improvement of fishing practice.
From the case studies, it can be seen that communication and education are vitally,
when introducing gear based measure into legislation. Regulations are in some cases
quickly introduced, but it takes time for the fishing industry to adapt. Case study 5
(blue whiting fisheries and the use of a flexigrid) illustrates that the compliance and

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ICES WGFTFB REPORT 2008
acceptance of gear measures can be high, as a consequence of the involvement of the
Faroese fishing industry in the actual fishing gear research and the implementation of
the legislation. The first case study (gill net fisheries and the use of pingers) however,
is a clear illustration where the very limited involvement of the fishing industry in
the development of Acoustic Deterrent Devices, its application and implementation
through legislation leads to much scepticism towards its use. The proven positive
effects of acoustic deterrent devices for certain cetacean species and fisheries have
been largely undermined and the measure has been ineffective in meeting its objec
tives.
Another vital aspect for an effective use of gear modifications is a good framing of the
legislation. There is a need to consider all relevant issues (e.g. practicalities, socio
economic and technical aspects, etc.) to ensure that gear measures, proven effective in
fishing gear research, meet their objectives after implementation.
Nonregulatory uptake of technical gear measures can be achieved through several
incentives. The incentives can be marketdriven, but uptake leading to an improve
ment of the fisheries image is also present. One example is the use of the benthos re
lease panel. In this case, the drivers are economic incentives and an improvement the
image of fisheries towards the public perception and supermarkets (achieved
through e.g. the UK Clean fishing competition). The use of selective methods by fish
ermen in other cases is apparent, when fishermen face or are subjected to a reduction
in fishing opportunities through other restrictive measures (e.g. access to closed ar
eas, increase in fishing days, etc.). This has been apparent in the adoption of the
Nordmore grid in Norwegian shrimp fisheries, where fishermen had to adopt more
selective gear to remain I the fishery (Graham et al., 2007).
WGFTFB conclude that the protocol used in the UKstudy (Catchpole et al., 2008) to
evaluate the legislation put into force for the C. crangon fisheries is both holistic and
effective. The same protocol can potentially be used elsewhere in other fisheries to
conduct similar evaluations on the efficacy of technical measures. This protocol in
cludes an evaluation of the legislation text, performance of the gear modifications,
including environmental effects and a socioeconomic evaluation. This can be sup
plemented by evaluating the efficacy of technical measures through proper use of
data gathered under the Data Collection Regulation, e.g. Enever et al. (submitted).
Data collection programmes can be used to evaluate the gear measures put into force.
However, these evaluations have to be used in association with survey data, to
document changes in discards and/or landings/catch.
16.1.4 Recommendations
1 ) WGFTFB recommends that WGECO use the findings of the case studies
presented in the context of the OSPAR QSR 2010.
2 ) WGFTFB recommends that the case studies presented be used to assist in
the development of a framework that can be used to assess the efficacy of
gearbased technical measures introduced to reduce the environmental
impact of fishing

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ICES WGFTFB REPORT 2008
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17
FAO Reduction of Bycatch in Tropical Shrimp Trawling (REBYC)
project
17.1 Overview
Frank Chopin and Janae Fogelgren, FAO, FIIT, Rome (Francis.chopin@fao.org &
Jannae.Fogelgren@fao.org)
The ICES Working Group on Fishing Technology and Fish Behaviour (WGFTFB) was
created in 1983. In 2002, the Food and Agriculture Organisation (FAO) joined with
ICES to cosponsor the WGFTFB, giving the working group a global mandate. Rec
ognizing the value of the WGFTFB and the need for enhanced collaboration between
ICES and FAO, a National Coordinators (NC) workshop of the FAOGEFUNEP pro
ject EP/GLO/201/GEF was hosted by FAO FIIT. Back to back meetings of the NC
workshop were held prior to the FTFB meeting.
The 2008 NC workshop was Chaired by Jonathan Dickson (The Philippines) and
Rapporteured by Oumarou Njifonjou (Cameroon). In order to make the results of the
NC meeting available to the ICES FTFB WG, three presenters [Jose Alio Latin Amer
ica, Bundit Chokesanguan ­ SE Asia and James Ogbonna ­ Africa] were selected to
present an update on bycatch reduction and change management activities from each
region to plenary. Additionally, each NC was offered the opportunity to present a
summary of their recent research in the form of a brief paper. This report contains
abstracts of each report submitted by each NC. More detailed reports are given in
Annex 12.
17.2 National Report Summaries
17.2.1 Philippines
Jonathan O. Dickson: Bureau of Fisheries and Aquatic Resources
(jod_bfar@yahoo.com)
The pilot implementation project was carried out in Samar Sea (Calbayog City) from
September 1, 2005 to December, 2006. The experiments involved 18 shrimp and fish
trawlers with a total landed catch of 1,295 tonne of fish from 991 fishing trips. The
average catch perunit effort (CPUE) for shrimp trawls (panghipon) was just below 1
tonne (948 kgs) per fishing trip while CPUE for fish trawl (palupad) was 2.4 tonnes per
fishing trip. Fishing season (peak months) was clearly identified as the months of Oc
tober and November with reduced catches in July August.
Of the total estimated catch of 711 tonnes from shrimp trawls for the study period,
more than one third (37.9%) was comprised of lizard fish (Saurida spp), followed by
nemipterids (Nemipterus hexodon, Scolopsis sp., 10%) and about 1% of shrimps. The dis
cards were comprised of juveniles of commercially important species as well as other
smallsized fish of low or no commercial value and are commonly utilized as aqua
culture feed was 15.6%. The composition of discards in shrimp trawls indicates a high
incidence of juveniles of commercially important species, among which were the liz
ard fish 8.1% (Saurida sp.), purple spotted bigeye 5.4% (Dilat, Priacanthus tayenus),
cardinal fish 9.2% (Muong, Apogon sp., hairtail (Espada, Trichiurus sp.).
The efficiency of JTED V15 for releasing trash/discard fish was the best device tested
Shrimp trawl with a reduction of 59%. V10 gave a reduction of 20% and this was way
below the set target of 40% and was therefore rejected during the 1st quarter of im
plementation trials. For commercial fish catches only the V15 gave a reduction of

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ICES WGFTFB REPORT 2008
10%, and this was apparently the reason why fishermen were hesitant in using this
device during the trials. H15 and V10 gave an increase of 11% in commercial catches,
while V12 gave an increase in 5%. With the fish trawls the reduction in trash/discard
catch was more apparent with the V12, V15 and H15 JTEDS with 54%, 58% and 46%
respectively. Again V10 with 20% gave reductions below the threshold. Interestingly,
the commercial catch indicated a significant increase with the V15 with a 66% higher
catch and H15 likewise gave an increase of 18%. Reductions in commercial catches
were observed with the V10 and V12 of 23% and 3% respectively.
A large amount of maturity data has been collected for Short bodied mackerel and
nemipterids species has a good data in terms of maturity. The data collected for
Rastrelliger kanagurta, locally known in Calbayog or Short bodied mackerel, showed
that its longest average length appeared in April with 225mm and its shortest average
length in May. Average length was found to be directly proportional to the highest
result on average Gonad Weight. The highest Gonado Somatic Index (GSI) was re
corded in April with 3.25 and 2.25 Gms, respectively. Mature samples were likewise
observed in April, May and July. Mature samples were further observed in October
and December. Most of the samples were, however, observed in April, which indi
cates that summer is the potential spawning season of this species. Nemipterids, as it is
locally known, in the area had its longest average length in August with 179mm and
its shortest average length in May (174mm). With regards to average GSI, December
showed the peak with 1.91 followed by September and October with 1.89 and 1.90
respectively. The same trend was seen with regards to average gonad weight. More
over, the majority of the samples gathered were immature (stages I III). Significant
percentages of fully mature samples were observed throughout the sampling period
with December showing the highest number followed by October and July, Septem
ber and November.
17.2.2 Southeast Asia
Bundit Chokesanguan, SEAFDEC, Thailand, (bundit@seafdec.org)
The demonstrations and experiments on the use of JTEDs were conducted in Thai
land, Brunei Darussalam, Vietnam, Malaysia, the Philippines, Indonesia and Myan
mar.Aside from the main aim on the introduction of the devices to member countries,
the research was also carried out to develop adjust and modify for the best perform
ance of the Juvenile and Trash Excluder Devices (JTEDs). Various kinds of JTEDs
were used in the experiment; there is Rigid Sorting Grid, Rectangular shaped win
dow and semicurved window with different grid intervals for each device. The re
sults show that each type and design of JTEDs gave different performance on
escapement rate of juvenile and commercial catch. The escapement rate ranged from
56.69­77% for juveniles and 9.72­47.31% for the commercial or target catch. Further
more the estimated selection curve of fish length was also considered. Based on this
experiment the Rigid Sorting Grid with 1.2 and 2 cm grid intervals gave better per
formance than other devices in maximizing the juvenile escapement while minimiz
ing the loss of commercial or target catch. The mean total length (TL) paralleled to the
size of the grid interval. It is recommended that the Rigid Sorting Grid with 1.2 and 2
cm grid intervals is appropriate to recommend to the region. However, other impor
tance factors such as the fishing ground, kind and size of target catch in each country
have to be well considered.

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ICES WGFTFB REPORT 2008
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17.2.3 Indonesia
Ari Purbatyanto, Faculty of Fisheries and Marine Sciences, Bogor Agricultural
University, Bogor, Indonesia
Research and engineering appropriate BRDs for developing the ecofriendly trawl net
in Indonesia were conducted on fishing ground around Dolak islands waters in Ara
fura Sea from November 29 to December 9, 2007. The flume tank demonstration was
performed at Fishing Technology Laboratory, Department of Fisheries Resources
Utilization, Bogor Agricultural University. The objectives of the research were to
evaluate technical performance of BRDs (TED super shooter, square mesh window,
and fish eye); to collect baseline data on the catch composition of trawl net without
BRD; to compare effectiveness of three different types of BRDs tested in reducing the
bycatch from a commercial shrimp trawl fishery in Arafura sea in term of changes in
catch composition, catch weight and catch value; and to demonstrate the BRDs per
formance in the laboratory flume tank.
The result of the study showed that the square mesh window and fish eye showed
similar good technical performance in comparison with the USTED. Although the
USTED has low technical performance, it was better than the standard TED, particu
larly from the view point of material used that give a little bit simple in handling
compared to the standard TED. The total of 26 hauls were carried out successfully
consisted of 45 species of fish, 2 species of shrimp, and some species of crabs. From
those species of fish, 21 species of economic fish was utilized by the fishers. The fish
eye has high effectiveness in reducing bycatch up to 13.36%, and then followed by
square mesh window (reduced the bycatch up to 5.98%). The USTED, however,
failed to reduce the bycatch (conversely increased the bycatch by 4.66%). All the
BRDs used have influenced on the shrimp loss i.e., 21.25% for the fish eye, 22.13% for
the square mesh window, and 32.29% for the USTED.
Flume tank observation from the three different types of BRDs showed a significant
technical performance and escaping behaviour of fish. The highest escapement of fish
was from square mesh window. Whilst the fish eye and USTED and fish eye have
low escapes. The position of fish eye and exit hole of the USTED has an effect to the
escapement process. The grid angle of 57.1º was suitable for allowing the unwanted
animal to escape.
It is recommended that three BRDs can be implemented. Although there are needed
further study to increase the effectiveness of the square mesh and fish eye, mainly to
decide the appropriate position of those BRDs on the codend for optimum function of
the BRDs to reduce the bycatch. Further research need to be conducted in long dura
tion of fishing trials that representing the fishing season.
Keywords: appropriate BRDs, ecofriendly, technical performance, catch composi
tion, effectiveness, bycatch, Arafura Sea.
17.2.4 Iran
A. Mojahedi, Iranian Fisheries Organisation, Deputy for Fishing and Fishing
Harbours, Tehran, Iran.
Research activities on Bycatch reduction started in 1992 at Persian Gulf Fisheries Re
search Centre (Boushehr) and First BRD fabricated in the same year. After these ini
tial measures, square mesh efficiency in Shrimp trawl net was investigated and 100

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mm Square mesh window, showed improved results in excluding small fishes. 2
years after the use of SMW was made obligatory in shrimp trawl nets and achieving
not ideal results, Iran Fisheries Organization in cooperation with FAO, launched new
round of experiments in 1997. Different types of BRDs have been experimented dur
ing these trials, such as: RES, NAFTED, Fisheye and cone. Initial outcomes showed
that NAFTED is efficient for excluding large aquatics.
Broad range studies performed during years 2000­2001, on bar devices (NAFTED &
Grid) and SMW comparison and results pointed out that Grid Type (NORDMOR
Grid) is the most efficient one comparing with other devices. Regarding achieving
results, during 2006, 100 Grid 8mm devices, have been fabricated and applied for In
dustrial trawlers.
Regarding this fact that, more than 90% of shrimp capture, harvested by artisanal
fishing vessels fleet and graduation adjustment plan for Industrial trawlers which
practically will reduce Industrial shrimp trawler numbers, therefore it is necessary to
experiment and promote BRDs on artisanal vessels. Then the aim of the project based
on excluding juvenile and small fish. All measures in project framework planned to
achieve this goal. Net modification is the first option for excluding juvenile and small
fish, and further options could be most effective device which will be selected
through experiments and advices we receive from international consultants.
17.2.5 Bahrain
Ebrahim A.A. Abdulqader, Bahrain Center for Studies and Research, Kingdom
of Bahrain, eabdulqader@bcsr.gov.bh
Among the 29 direct fisheries identified in the Bahrains waters it believed that
shrimp trawling and Spanish mackerel drift gillnetting are responsible for most of the
bycatch quantities generated in Bahrains waters. 315 boats are involved in shrimp
trawl fishing; while small boats made up 24% of these boats. The 1999­2000 BRD tri
als were the only systematic work conducted in Bahrain. The experimental Bycatch
Reduction Device (BRD) is composed of an ovalshaped solid grid and 2 radius
square mesh (RSM) to exclude at two stages large animals and smaller finfish species
respectively. The overall results suggested a 30% reduction in finfish species on a
weight basis, while it maintained crab and shrimp catches. BRD experiments revealed
that among the 92 finfish species found in the bycatch, 30 finfish species were able to
escape from the net and 14 finfish species were unable to escape. This BRD experi
ence indicates that increasing the selectivity of trawl nets is beneficial to the shrimp
fishery and maintains the biodiversity of the marine habitat. It also suggests that se
lectivity is an effective management measure to reduce the fishing intensity on Bah
rains shrimp stocks. Despite the early participation of the Kingdom of Bahrain in this
GEF/FAO global program, the benefits obtained are minimal. Several concepts are
outlined to form the core of a future national plan for Kingdom of Bahrain under this
global program.
17.2.6 Cuba
Luis Font Chávez, Fishery Ministry, Havana, Cuba, jfont@cip.telemar.cu
Constructive characteristics of trawl nets used in tropical shrimp fisheries, present a
marked negative effect on benthic populations and bottom species, constituting a
threat for conservation of biological diversity and marine environment. Nevertheless
and taking into account that the catch of this resource represents an important eco
nomic and social source, it is necessary to promote the use of lower impact catch

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technologies and that their introduction in the fishery be technical and economically
feasible. Results reached up to present in the project have been aimed to the design,
construction and test at experimental and commercial level, in Santa Cruz del Sur
Fishing Enterprise, of a less harmful fishing technology to environment, being veri
fied important advantages as: to allow an escape of near 25% of bycatch, thus reduc
ing the negative effect on fish populations and specially juvenile stages of Lane
snapper (Lutjanus synagris) and also increasing the fishing gear selectivity to the catch
of Pink shrimp (Farfantepenaeus notialis), with no detriment of the present observed
levels and consequently an increase in the catch exportable value. At the same time,
regulatory measures on the fishery have been dictated which substantially contribute
to the protection of shrimp populations and species composing bycatch. Other fore
seen results are related to the reduction of net constructive costs and fuel consump
tion. Project execution has been characterized by the active participation of managers,
technical personnel of the Enterprise, as well as captains and fishermen of shrimp
vessels, who have contributed with valuable experiences and practical execution in
the project development by participating in cruises, conferences, workshops and ad
vanced qualifying courses for the personnel dedicated to net construction. The new
fishing system will be introduced in Santa Cruz del Sur Fishing Enterprise at the end
of ban of 2008­2009 seasons.
17.2.7 Trinidad and Tobago
Suzuette Soomai, Fisheries Division, Ministry of Agriculture, Land and Ma
rine Resources, soomaisue@yahoo.com
Three periods of gear trials were conducted over 2006 and 2007 in the artisanal fleet
and one period in 2007 in the semiindustrial and industrial fleets, overall covering an
estimated 25% of the national trawl fleet. Gear trials involved modifying the existing
trawl net, testing of two bycatch reduction devices (BRDs) namely the fisheye and
square mesh panel, and testing of a new monofilament trawl net received from Mex
ico and aimed at reducing the level of discards of bycatch caught in the artisanal
shrimp trawl fishery. Overall results are insufficient to determine the effectiveness of
each BRD in reducing discards. Modifications to the existing net and the new mono
filament net however showed favourable results with regard to making fishing op
erations more efficient. Joint gear testing between the Fisheries Department and the
fishing industry has been beneficial in educating fishers and promoting co
management of the trawl fishery. Technical assistance from the National Fisheries
Institute of Mexico and from the FAO was instrumental in technology transfer and
enhancing fisheries research in Trinidad and Tobago. Gear testing allowed for col
laboration with Venezuela on joint research in the Gulf of Paria and the Columbus
Channel where the shrimp and groundfish resources are shared.
17.2.8 Venezula
Luís Marcano and José Alió, (lmarcano@inia.gob.ve ; jalio@inia.gob.ve
Discarded by catch of the industrial shrimp fleet in Venezuela is about 60% and is
considered a major environmental impact in the country. Tests were conducted to
reduce discards in the industrial and artisanal shrimp fleets. The industrial shrimp
fishing is performed by 260 Florida type vessels, targeting shrimp and fish. The use of
TED is mandatory. Testing of bycatch reductions devices (BRD) like fish eye showed
a significant reduction in discards but also severe losses of commercial catch. The
square mesh panel did not provide significant reductions of discards. The lower or
lifted lower rope rendered an average 25% reduction in discards and no significant

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ICES WGFTFB REPORT 2008
loss of commercial catch. The artisanal shrimp fishing is done with small trawls and
beach seines. The former was modified with Nordmore grid, square panel and fish
eye. Better results were obtained with the fish eye, which showed a reduction in dis
cards close to 70%, but a 30% shrimp loss was confronted. Tests of BRDs will con
tinue after FAOGEF project ends in 2008, organizing workshops with fishers to show
construction and use of the devices, and sharing of results with researchers and fish
ers of countries in the region is to be promoted.
17.2.9 Mexico
Dr Miguel Angel Cisneros Mata, Chief Director, Instituto Nacional de Pesca
PACIFIC COAST
A 10 day's cruise onboard commercial vessel at the west coast of Baja California Pen
insula face operations problems since there was a huge presence of a crustacean
known as "langostilla" (Pleuroncondes planipes); trawls sets were rather short and
non representative in all shrimp fishing ground areas.
Due to engine brakedown of BIP XI, an 8 days cruise for sea trials in the Upper Gulf
of California was made; results confirmed advantages of prototype RSINPMEX, in
previous trials. Comparison of bycatch reduction and catch efficiency of prototype
was possible since a set of traditional trawl nets were tested; all expenses were cov
ered by the Walton Foundation through WWF.
ATLANTIC COAST
Arrangements were made to use commercial trawlers for testing of new net designs
and the introduction of BRDs at Tampico, Tamaulipas and Ciudad del Carmen,
Campeche. Since the fleet composition and technical characteristic of trawl nets has
changed, a survey was carried out in those two ports, for data collection of 30 shrimp
trawlers.
Two meetings were held with vessel owners from the Atlantic coast, where the
stockholders asked to include testing of new otter boards (High Lift) used in the Pa
cific phase of the project, in order to achieve further fuel savings.
Due to lack of researchers it was decided that all sea trials were going to have place
during the shrimp ban of the Atlantic; cost of testing/fishing operations will be cover
by the stockholders, except DSA payment of researchers and new gear and devices.
Research for artisanal shrimp fisheries have started in the Upper Gulf of California in
order to reduce the impact of enmeshing shrimp nets on endemic endangered por
poise (Vaquita); also, due to mixed presence of juvenile white shrimp (Litopenaeus
setiferus) while trawling for REBYC
Reduction of Environmental Impact from Tropical Shrimp Trawling, through the in
troduction of Bycatch Reduction Technologies and Change of Management Sietebar
bas shrimp (Xiphopenaeus kroyeri), a new project will start in 2008 in the Atlantic coast,
to introduce a new trawl net with short front upper panel or no front upper panel.
17.2.10
Columbia
Mario Rueda & Farit Rico, Instituto de Investigaciones Marinas y Costeras (In
vemar), mrueda@invmar.org.co
Quantification of tropical shrimp trawling impacts and mechanics to reduce it on
both on Caribbean and Pacific coasts were evaluated. The methodological approach

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included census of the fishing technology, monitoring, workshops, trials and fishing
experiments. The census revealed that vessels and net designs are more than 30 years
old. Monitoring of fishing operations showed the following catch composition:
shrimp 8%, incidental catch 27% and discards 65% for the Caribbean; while for the
Pacific shrimp is 5%, incidental catch is 43% and discards is 52%. With this in mind
new trawl nets were designed, introducing new netting materials and BRDs (fisheye
and TED). 12 Trawl nets prototype were manufactured during 2 workshops, where
60 fishers were trained in fishing trials. These trawl nets were used in fishing experi
ments comparing catches of an experimental vessel (using prototype nets) with those
of a control vessel (using traditional nets) to test reduction of bycatch and fuel con
sumption if possible. For the Caribbean 80 hauls paired showed that the bycatch was
reduced as follows 20% (fisheye), 41% (TED), 54 (fisheye + TED); while for the Pacific
240 hauls showed reductions of 28% (fisheye), 23% (TED) and 57% (fisheye + TED). In
the Caribbean the fuel saved was 17%, whereas on the Pacific the save was 25%. Cur
rent decrease of the shrimps stocks and high fuel prices, are part of the issues that the
fishery management agency in Colombia faces to change of management.
17.2.11
Costa Rica
Antonio Porras Porras, INCOPESCA, porrasantonio1@yahoo.com
Costa Rica is localized in Central American. In Costa Rica, the project concerns Pacific
waters. This area has all shrimp trawling fishery, but which are currently severely
threatened by over fishing, contamination and global environment effects. The pro
ject is under the supervision of the Costa Rican Institute of Fisheries and Aquacul
ture, INCOPESCA. The semiindustrial sub sector has 72 registered shrimp trawlers
vessels (49 operating) based in Puntarenas. These vessels are shrimp trawlers with
large quantities of juveniles. Bycatch and trash fish constitute mostly 70% of the
products caught.
Sea trips were organized from June 2007 to March 2008 and were undertaken on
board of the commercial vessel "Cap. Yerald". This vessel reduced the expenses in
the research phase (in kind contribution of the private sector). The trawler used two
nets while fishing. This practice permitted a comparative study between the proto
type net, the traditional net, and tested BRD's. The Square mesh window and the eye
fish inside of the codend.
Eleven fishing trips were carried out and included fifty four tows, each of this trawl
ing were of five of six hours long. However, in a preliminary way, we obtained at
least a 20% reduction of bycatch and the conclusion that for each kilogram of shrimp,
seventy kilogram of bycatch are fished.
The National coordinator participated on two training/demonstration activities or
ganized in Cuba and Mexico (Demonstrations/SeaTrials on fisheye BRDs and
Suripera net used). Two training workshops on BRDs and Prototypes net were organ
ized and some fishermen and net makers were trained on how to build the nets. A
practical training was also organized on board of a commercial vessel in Puntarenas.
Two kinds of BRDs, the Square mesh window codend and the fisheye were tested
and compared with a traditional codend. Three workshops on REBYC and Costa Ri
can Project result were organized in El Salvador, Nicaragua and Panama countries in
April, 2008. Sixty five participants were in these workshops (three day for each one)
and to fishers, stakeholders, technicians, and governmental authorities were prepara
tion.

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17.2.12
Nigeria
James Ogboona, Nigerian Institute for Oceanography and Marine Research
(NIOMR), Lagos, jamescogbonna@yahoo.com)
Nigeria is one of the participating countries involved in GEF/UNEP/FAO Shrimp
Fisheries Project titled: `Reduction of Environmental impact from Tropical Shrimp
Trawling through the introduction of Bycatch Reduction Technologies and change of
management'. The main objective is the reduction of bycatch in shrimp fisheries.
Nigerian Institute for Oceanography and Marine Research, (NIOMR) Lagos is cur
rently implementing 2 complementary research activities in the Eastern Gulf of
Guinea sub region of West Africa on the following:
a ) The development/adaptation of appropriate bycatch reduction tech
nologies for the shrimp trawlers in Nigeria and Cameroon. This tech
nical part of the project involved the construction of prototype Bycatch
Reduction Devices (BRDs) and Turtle Excluder Device (TED) for fleet
testing on board conventional shrimp vessels in Nigeria and Camer
oon. The awareness created has extended to other States in the sub re
gion including Togo Republic, Republic of Benin, Gabon, Sao Tome &
Principe and Equatorial Guinea.
b ) The design and conduct of a socioeconomic survey of the shrimp
trawl fisheries and the trading of their bycatch
The technical development/adaptation of reduction technologies Turtle Excluder De
vices (TEDs) are installed in the codend extension of shrimp trawl nets as a manage
ment tool to reduce fishery related sea turtle mortality. Trawl nets with bycatch
reduction devices (BRDs) are also constructed in order to mitigate the problem of ju
venile and immature fish bycatch in shrimp trawling. The combinations of TED and
BRD in the same trawl net are expected to function perfectly well and complement
each other without any drastic reduction in the quantity of shrimps. The data re
corded during comparative demonstration trials of trawl nets fitted with TED, BRD
codends and the traditional square mesh codend, are shown in Table 1. As shown in
Table 2 the results of analysis of variance (ANOVA) indicated that there was no sig
nificant variation in the mean values of shrimps caught by the various trawl net
codends.
17.2.13
Cameroon
Oumarou Njifonjou, IRADSRHOL PMB, Cameroon, (Njifonjo@caramail.com)
In Africa, the project concerns Nigeria and Cameroon waters. This area has vast fish
eries resources, which are critical to the food security of the region, but which are cur
rently severely threatened by over fishing, urban runoff and offshore petroleum
exploitation. The project is under the supervision of the Fisheries Department and is
implemented in Cameroon by the Fisheries and Oceanography Research Station
(SRHOL). The Artisanal shrimp fisheries utilizes more than 1000 fishermen and for
the moment the Industrial sub sector has 41 registered shrimp trawlers from Nigeria
and 30 based in Douala. Most of these vessels are shrimp trawlers with small mesh
sizes and this inevitably results in large quantities of juveniles. Bycatch and trash fish
constitute mostly 95% of the products caught and 75% of the finfish landed are juve
niles caught before first maturity. The increase of the shrimp fishing effort over the
years, the high level of fish caught by shrimp trawlers, the continue reduction of the

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sizes of fish landed, the high price of fish on the markets and the political will to con
serve and sustain the fisheries resources are the main motivation for the establish
ment of bycatch reduction legislation/regulations. In the new fisheries Law to be
promulgated, BRDs and TEDs utilization has been introduced as one of the basic re
quirements for the license application.
17.3 List of Participants
Andres Seefoo
INAPESCA
Mexico
Antonio Porras
IFA
Costa Rica
Bundit Chokesanguan SEAFDEC
Thailand
Frank Chopin
FAO
Italy
James C. Ogbonna
Fisheries Dept
Nigeria
Janne Fogelgren
FAO
Italy
Jonathan Dickson
BFAR
Phillipines
Jose Alio
INIA
Venezuela
Luis Marcano
INIA
Venezuela
Mario Rueda
INVMAR
Columbia
Oumarue Njifonjou
IRAD/SHOL
Cameroon
17.4 Conclusions
In 2008, REBYC I will come to an end. Significant progress has been made towards
reducing the bycatch of large charismatic species such as marine turtles captured by
tropical shrimp trawls, however, significant problems remain with respect to the cap
ture of juvenile fish and sustainable management of tropical mixed species bottom
trawl fisheries.
It is the hope of FAO and the NCs that a second phase project will be implemented
and broadened to a greater number of countries and incorporating a broader range of
management tools to manage multi species trawl fisheries. This approach is echoed
by the EC in European Parliament Resolution P6_TAPROV (2008) 0034 on Reduc
tion in unwanted bycatch and elimination of discards in European Fisheries. Given
then there are other concerns with bottom trawls that also need to be addressed, per
haps there is the opportunity for an International Plan of Action.
Discussion
Questions were raised as to why fishermen continue to use BRDs if they are losing
income. A number of the FAO representatives replied to this. In the case of Nigeria
there had been a certain amount of embarrassment at government level with the high
level of bycatch, so they made the use of BRDs and TEDs are compulsory but intro
duced a fuel subsidise to incentives compliance. In Mexico there are no economic
gains in landing bycatch and there are incentives such as reduced fuel consumption,
improved catch quality and saving sorting time so using the devices is acceptable to
fishermen. In the Philippine although there is are some financial gains from landing
bycatch species, financial support from fishing companies has encouraged fishers to
use BRDs.
The analogy of US imposing trade embargoes on countries whose fleets did not use
TEDs in shrimp fisheries was used to indicate how economic drivers are a strong in
centive to adopt selective gears. It was stated that a similar policy may be applied by
the US in the near future with the use of circle hooks being made mandatory in sur
face longline fisheries for tuna and swordfish fisheries.

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18
Summary of Other Presentations
An open session was held on Tuesday 22 April at which the following presentations
were given to plenary.
18.1 Nordic Project; Research in big mesh pelagic trawls
Frodi B. Skúvadal
Faroese Fisheries Laboratory, Noatun 1, P O Box 3051, Tórshavn, Faroe Islands
Abstract
A Nordic project involving the Faroe Islands, Iceland and Norway researching pe
lagic trawling is being undertaken with funding from the Nordic Council. The focus
areas of this project are optimization of large mesh pelagic trawl designs, with re
gards to water flow and fish behaviour, minimizing bycatch of non target species and
the use of pelagic trawls for demersal species. The pelagic fisheries in these countries
are similar with regards to fishing units, gear and fished stocks. The form of the col
laboration is through workshops, participation on cruises and collaborative meetings.
Measurements of flow have been made with ADCPs (Acoustic Doppler Current Pro
filers) that measure speed and direction of the flow in a profile inside the trawl. The
methodology is to use one ADCP on the headline and one in the belly section, close to
the codend. Collections of escapees have been carried out by means of small mesh
collection bags attached to the aft belly of the trawls. Observations of fish behaviour
have been made with acoustic and optical devices.
Preliminary Faroese results from flow measurements inside large mesh pelagic trawls
suggest that there is a reduction of two thirds in velocity in front of the codend com
pared with the velocity at the headline. These measurements were made in a 2300 m
pelagic trawl with a 70 m long codend. Results indicate that the size of the codend
has a reducing effect on the water velocity in front of the codend. Further flow meas
urements and behaviour observations of fish inside the aft belly of pelagic trawls will
be made in 2008 and 2009.
Discussion
It was pointed that the Dutch had conducted experiments with similar measurements
and found that T90 releases more water than standard diamond mesh. It was also
explained that there is a need to be careful when interpreting the results from other
referenced studies on flow changes around trawls as most of them were conducted in
much smaller gears which may not be representative.
18.2 Direct observations of large mesh capelin trawls; evaluation of mesh
escapement and gear efficiency
Haraldur Arnar Einarsson, Einar Hreinsson, Sigurður Þór Jónsson,
MRI-Iceland
Abstract
This paper describes methods for observing large pelagic capelin (Mallotus villosus,
Müller) trawls, evaluation of meshing and mesh escape, in situ school density and
catching efficiency. Gear monitoring sensors were used to measure gear opening pa

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rameters and vertical position. Information on trawl geometry was collected with a
headline sonar, sonar and cameras mounted on a remotely operated towed vehicle
(ROTV), and data from depth recording sensors. The cross section area for each net
section was used to calculate the volume of seawater filtered by each mesh size. Cap
elin behaviour was observed by the use of underwater cameras, HLsonar, and ROTV
mounted sonar. Acoustic data were collected with a calibrated 38kHz echo sounder
to evaluate mean volume density of capelin in number of fish per cubic metre. The
observations provided valuable information's of the gear shape and performance.
Capelin showed strong reaction to artificial light, by swimming downwards few sec
onds after the lights were turned on. Capelin was seen escaping mesh sizes from 80
mm to 16 m. Meshing was recorded in 80 to 800 mm meshes, highest in the 80­160
mm range. Sonar images showed both escaping capelin and capelin being herded in
mesh sizes from 16m down to 200 mm. No escapement was recorded through meshes
60 mm and smaller. Measurements of trawl geometry, capelin density, and catch vol
umes, indicate low catching efficiency. A theoretical model for quantitative estimates
of the efficiency, based on cross section density measurements, and a practical meth
odology for acquiring such density measurements are described in the paper.
18.3 Design and test of a topless shrimp trawl to reduce pelagic fish bycatch in
the Gulf of Maine pink shrimp fishery
Pingguo He1, David Goethel2 and Tracey Smith1
1 Ocean Process Analysis Laboratory of Institute for the Study of Earth, Oceans and Space
and New Hampshire Sea Grant, University of New Hampshire, 142 Morse Hall, Durham,
NH 03824, USA. Email: pingguo.he@unh.edu. 2. F/V "Ellen Diane", 23 Ridgeview Terrace,
Hampton, NH, USA 03842
Abstract
A new innovative shrimp trawl was designed, and tested in the flume tank, and at
sea to evaluate its potential of reducing finfish bycatch in the pink shrimp fishery in
the Gulf of Maine. The trawl design removed the square and the top part of the sec
tion after the square (first belly section), to become "topless". A fiveday sea trial was
carried out using the alternative tow method to compare the new topless net and a
control net (commercial net). The target species was the pink shrimp (Pandalus bore
alis) and the major bycatch species was Atlantic herring (Clupea harengus) (90.6% of all
bycatch by weight). Comparative fishing indicated that the new topless net reduced
bycatch of Atlantic herring by an average of 86.6%, and at the same time produced a
modest increase (13.5%) in the catch of the pink shrimp. There was some increase in
the bycatch of flounders (American plaice, Hippoglossoides platessoides, and winter
flounder, Pseudopleuronectes americanus), though overall amount of flounder bycatch
was less than 1% of the total catch. The reduction of herring was most likely due to
the fish escaping over the headline where the top panel was removed. The increased
bycatch of flounders (and increased catch of shrimp) might have been resulted from a
wider wing end spread and subtle differences in the footgear between the new and
control nets. The substantial reduction of the major bycatch species (herring) without
a reduction of target species (shrimp) proved the concept of the topless shrimp trawl
and may have a profound impact on other shrimp trawl fisheries around the world.

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Discussion
The author was asked if diurnal effects were taken into account but as essentially this
is a daylight fishery, the experiments were conducted accordingly during daylight
hours so diurnal effects were not an issue. It was also stated that the shrimp rise dur
ing the night. The question was also raised if there was difference in fuel consump
tion with the new design. This was not specifically measured but drag of the new
gear was similar at the same towing speed to the conventional gear.
18.4 FISHSELECT - a tool for predicting basic selective properties for netting
Bent Herrmann, Ludvig A. Krag, Rikke P. Frandsen, Niels Madsen, Bo
Lundgren
DTU Aqua, Technical University of Denmark
Abstract
In towed fishing gears like trawls, technical regulations aim at retaining marketable
fish and releasing nonmarketable fish. Different species have different morphologi
cal characteristics such as crosssection shape and their potential for deformation dur
ing mesh penetration. Identifying the optimal mesh size and mesh shape is therefore
a complex procedure depending both on the species morphology and the defined
minimum landing sizes (MLS). We present a new methodology, FISHSELECT, devel
oped to make a first prediction of the basic selective properties of different netting
panels. By applying the methodology and the specially developed tools, we identify
and record the species specific morphological features that are decisive for mesh
penetration. Data on these features are processed in an integrated software tool to
produce design guides for different netting panels. The design guides provide a
powerful tool that facilitates the predictions of optimal netting designs for a given
fishery. Examples on application of FISHSELECT are presented for Cod, Haddock,
Plaice, Turbot, Lemon Sole, Sole and Nephrops.
Discussion
The question was raised whether the model takes into account rigormortis effects in
the "Fall Through" experiments. The author replied that this affect was expected to
be significant and so fresh, very recently killed fish were used for this reason.
Regarding seasonal variations in morphology for given lengths of fish, this was not
studied fully but will be taken into account in future work. However, the experience
with cod at pre spawning stage in January did not show much difference as the com
pressed morphology for this species did not change much.
It was highlighted that simulations made in the study confirm that for round fish us
ing square mesh is the optimum way to reduce the variation in selectivity by main
taining a relatively constant mesh shape but for flat fish L50 is reduced in square mesh
codends.

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18.5 Technical and selective properties of T90 meshes codend-extension
tandems made of different netting stiffness
W. Moderhak,
Sea Fisheries Institute, 81­332 Gdynia, ul. Kollataja 1, Poland
Abstract
Four T90 codendextension combinations were investigated on the Polish research
vessel BALTICA in years 2006 and 2007. The study showed that the construction of
the extension influenced the selectivity of the codend even if the codend has the same
construction each time. The results obtained during the study show that the best solu
tion is when the codend and the extension are made of the same netting, or when the
extension is made of stiffer netting than the codend. Studies in this subject should be
continued.
Discussion
The question was raised if catch quantities in the codend as taken into consideration
in the experiments. The author replied that the catch was stimulated by drag for
which the corresponding catch amount was unknown. A previous study by O'Neill
et al (2004) was referred to which attempted to measure the drag forces acting on
codends.
18.6 Fuel Saving Initiatives in the French Fishing Industry
Benoit Vincent,
IFREMER, Lorient, France
Abstract
The Fishing Gear Technology unit of IFREMER has been working on energy savings
for some years. We present different applications, particularly collaboration with
tropical shrimp Malagasy fishing companies and collaboration with regional fishing
companies. The work is based on an optimization of the trawl and doors, using flume
tank trials and numerical simulation. The method used is detailed as well as typical
results and potential savings. The importance of the communication and exchange
with fishermen and net makers are also underlined.
Discussion
The question was raised as to whether with the low drag gear whether there was dif
ference in catch efficiency. The author replied that there was not in Madagascar but in
the shrimp fisheries, fishers preferred to use smaller meshes in the rear part of the
net. It was felt that the low drag nets may not always work in certain conditions such
as high current or bad weather. Therefore, there is need for them to be tested in a va
riety of conditions before suggesting to the industry for commercial uptake.

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18.7 Modelling flow through and around nets using computational fluid
dynamics
Øystein Patursson
Abstract
Computational fluid dynamics (CFD) modelling and measurements have been used
to investigate current flow through and around net panels and fish farming cages.
For the numerical computations a porous media model was used to represent the net
allowing efficient computation of both exterior and interior flow fields. The model
was calibrated using tow tank measurements on a net panel at different velocities and
angles of attack. The CFD method was able to reproduce the drag and lift coefficients
of the net panel and the velocity reduction behind the net panel with satisfactory ac
curacy.
The approach was validated for a small size gravity cage by comparing CFD predic
tions with tow tank measurements of drag force on the cage and velocity reduction
inside the cage and in the wake region. The validation process showed very good
agreement between measured and modelled velocities inside the cage and a slight
discrepancy in the wake region.
The same approach should be applicable to trawls as well, but a new study is needed
for the calibration and validation of the model to different types of net and the new
geometry.
Discussion
It was highlighted that for the trawl simulations there is a need to find a new system
without using fixed frames. It was pointed that rigid net elements may be a solution
and work done in East Germany and at the University of Arnhem using a lattice grid
arrangement were referred too.
18.8 Comparison of selective properties for nettings when used in normal
direction versus in 90 degrees turned direction (Poster)
Bent Herrmann, Ludvig Krag, Niels Madsen
DTU Aqua, Technical University of Denmark
Abstract
Experimental studies have indicated that the size selective properties of normal (T0)
diamond mesh nettings used for trawl codends can be improved by turning the net
ting orientation 90 degrees (T90). The potential effect of T90 has also been investi
gated by simulation techniques. A T90 codend has been introduced in the Baltic cod
fishery as a legal alternative to the BACOMA codend. But how big is the T90 effect
and how dependent is this effect on the varying loading acting on the netting
throughout the fishing process? How dependent is this effect on the netting charac
teristics like mesh size and twine thickness? We apply the FISHSELECT and NETVI
SION methodologies in a pilot study to demonstrate how the T90 effect can be
investigated and quantified. Initial results for a few netting designs are reported to
demonstrate the applicability of the used methods.
NETVISION is a method to acquire and describe shapes of meshes in trawl nettings
when these are loaded in directions T0 and T90. NETVISION uses image analysis

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techniques to collect the mesh shapes data in a netting panel. The extracted mesh
shapes are loaded into FISHSELECT to predict and compare estimates for L50. FISH
SELECT and NETVISION can handle parametric as well as nonparametric mesh de
scriptions. By combining NETVISION and FISHSELECT we quantify the difference
between T0 and T90 netting for different loading situations and estimate the T90
EFFECT based on the ratio between the estimated L50 values. If the T90 orientation
has a higher L50 value than the T0 orientation then the T90EFFECT is larger than 1.0
for that specific loading situation. This is exemplified for cod based on FISHSELECT
data. We used four pieces of netting with quite different characteristics with respect
to the ratio between twine thickness and mesh size and investigated the influence of
these design parameters on the T90EFFECT. Based on realistic estimates of the drag
forces acting on codends when towed we investigated four different loading condi
tions.
The shapes of meshes in four different nettings under different loading conditions are
shown. The T90EFFECT is quantified in each case. The results imply that the T90
EFFECT is dependent on the loading condition and is affected by the netting charac
teristics. For a net with a relatively large mesh size compared to the twine thickness a
relatively small load will close the meshes in both netting orientation (T0 & T90). The
opening of a fully stretched T90mesh is defined by the size of the knot which is small
for netting 1 due to the thin twine. A larger T90EFFECT is found for nettings 3 and 4
where the mesh size is relatively small compared to the twine thickness. This will
increase the mesh resistance against closure for the T90orientation thus requiring a
larger load. The thicker twine results in a larger knot size thus improving the shape of
the fully stretched mesh in the T90orientation. Results for netting 2 are between
those found for netting 1 and for netting 3­4.
This pilot study demonstrates the potential of using FISHSELECT and NETVISION
to investigate and quantify the selective properties for nettings under varying loading
conditions. The preliminary results imply that:
· The T90orientation can improve the size selection for cod compared to the
T0orientation.
· The T90EFFECT is very depending on the loading condition acting on the
netting and on the characteristics of the netting (mesh size and twine
thickness).
We recommend that the combination of NETVISION and FISHSELECT is integrated
into future studies dealing with technical regulations of towed gear because:
· Together the methods can be used to quantify and compare the size selec
tive potential of different netting including those legally used today.
· Together the methods can be used to improve the understanding of the in
fluence of the netting characteristic on the selection process and thereby
contribute to a use of more optimal netting designs in towed fishing gear.
18.9 Simulation-based study of precision and accuracy for methods to assess
size selective properties of codends (Poster)
Bent Herrmann,
DTU Aqua, Technical University of Denmark

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Abstract
Two different methods, the covered codend and the paired gear method, are often
used to experimentally assess the size selective properties of different gear designs.
But how efficient are these methods compared to each other? Especially how many
fish is it necessary to catch and measure to obtain results with a given precision with
the two methods? Do the results tend to be biased or not when the number of fish
included in the assessment is decreased? This is investigated for a single scenario us
ing a simulationbased approach.
A special facility in the FISHSELECT software tool enables production of virtual re
tention data of a similar structure as would be obtained in an experimental fishing
process using a twin trawl design where the test codend also has a small mesh size
cover codend. For each length class the number of fish in three different compart
ments: test codend, cover codend and control codend was obtained. To estimate the
sizeselective properties of the test codend two different methods were applied: cov
ered codend (using data in test and cover) and paired gear (using data in test and
control). Data for single hauls were analyzed according to the procedures described
in ICES report 215. First a baseline haul containing 10000 fish was simulated contain
ing more than 250 fish in each length class thus minimizing binomial effects that
dominates when length classes only contain a small number of fish each as would be
the case with very limited catch or heavy subsampling. With the FISHSELECT soft
ware tool the baseline haul was used to produce subsamples from each compartment.
For each subsample rate 500 repeated samples were drawn from the full sample. The
simulations were performed for cod in a 100 mm mesh size diamond mesh codend to
produce realistic selection results. 2 x sd was applied to estimate the 95% confidence
bands for L50 and SR. Equal fraction subsampling was performed, that is, sub. rate
90% means that 10% (100 90) of the fish in the test, cover and control were each ran
domly selected and included in the estimation of L50 and SR in the individual
"hauls".
Because the obtained results are only based on one simulation scenario results can be
different for other scenarios. Definitive conclusions will require a more comprehen
sive study to be carried out. Likewise uncertainties in the relative sampling rates be
tween cover and test are not included. But the following observations can be made:
· To obtain the same precision for L50 and SR the covered codend method
requires much fewer fish to be caught and measured than the paired
method.
· The covered method produces unbiased mean results for L50, while mean
SR tends to be biased slightly downwards for small amounts of fish.
· For the paired method mean SR tends to be increasingly biased down
wards when estimates are based on fewer fish.
· The Pvalue alone is a poor indicator for the quality of the estimates of L50
and SR since it (as expected) tends to increase as the data gets weaker (es
timates based on fewer fish). Contrary does the R2value tends to decrease
as data gets weaker.

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19
National Reports
The contents of the individual National reports are NOT discussed fully by the
group, and as such they do not necessarily reflect the views of the WGFTFB.
19.1 Belgium
Institute for Agricultural and Fisheries Research
EU-project: "Development of fishing Gears with Reduced Effects on the Environment"
(DEGREE) (Contract SSP8-CT-2004­022576)
This projects aims at the investigation of ways of reducing the environmental impact
of beam trawl fisheries (reduction of discards of noncommercial fish and inverte
brate species and undersized commercial fish species) and the possible solutions to
technical drawbacks for voluntary implementation in the Belgian beam trawl fleet.
Contact : Jochen Depestele (Jochen.depestele@ilvo.vlaanderen.be)
FIOV-project: "Alternative beam trawl"
This projects aims at the investigation of reducing the environmental impact of beam
trawl fisheries (reduction of discards of noncommercial fish and invertebrate species
and undersized commercial fish species) and reduction of fuel consumption. Several
technical modifications are combined in the beam trawl such as a benthos release
panel, more selective codends, large meshes in the top panel, lighter chains and roller
gear. A voluntary experimental phase and a voluntary uptake by the industry is en
visaged. Already an industry working group has been established with trials on
board commercial vessels. Contact: Hans Polet (hans.polet@ilvo.vlaanderen.be)
National project: "Evaluation of the ecosystem effects of Trammel net and Beam trawl
fisheries at the Belgian Continental Shelf" (WAKO) [Work package within the project
"Innovation Centre Sustainable and Ecological Fisheries" (project° VIS/02/B/05/DIV)]
This project aims at the investigation of the ecosystem effects of trammel net fisheries
for sole and beam trawl fisheries for flatfish at the Belgian Continental Shelf. Existing
data from several Belgian institutes and a literature review have been conducted to
investigate the possibilities for an integrated evaluation of fishing impacts of different
fishing methods. Three ecosystem components were under consideration: benthic
invertebrates, seabirds and marine mammals. Contact: Jochen Depestele
(Jochen.depestele@ilvo.vlaanderen.be)
National Project "Trammel- and gill net fishing, traps and pots" (project°
VIS/07/B/01/DIV)
This project aims at the testing of various static gear, traps and pots in order to de
termine the possibilities of multipurpose, alternative fishing methods. The fishermen
need to be able to diversify throughout the year to target various species at optimum
times of the year. Protecting spawning periods, reduction of bycatch and selectivity
are important. By means of a broad range of various static gears, fisherman will be
able to be flexible for the whole year and change fisheries depending on market de
mand. By means of exploring these fishing methods, we can offer an alternative for
beam trawl fishing and attract new investors, which is essential for the basis of a
whole new versatile and profitable fishing fleet.

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ICES WGFTFB REPORT 2008
Additional funding for five years has been requested to extend this project and have
sought other external partners regarding further development. Contact: Dirk Ver
haeghe (dirk.verhaeghe@ilvo.vlaanderen.be).
Project alternative fisheries (projectn°VIS/02/B/07/DIVb)
Contact : Kris Van Craeynest (kris.vancraeynest@ilvo.vlaanderen.be).
National Project: "The impact of fishing gear on fish quality" (traditional versus alter-
native beam trawl) ­ (project° VIS/07/B/02/DIV)
This project aims to verify if sole and whiting caught with an alternative beam trawl
(at least equipped with a T90 net or benthos release panel) are of a better quality
than these caught with a conventional beam trawl. The basis of comparing will be the
"Quality Index method", PH and Total volatile base analysis and the "Injury Index
Method" under development.
There is a growing opposition against beam trawl fishing so every bit of upgrading
and improvement of this fishing method needs to be verified before switching over to
alternative methods. The consumer market is demanding improved fish quality
linked to sustainable fisheries where upgrading efforts have been already carried out.
Additional funding for five years has been requested to extend this project and have
sought other external partners regarding further development. Contact: Dirk Ver
haeghe (dirk.verhaeghe@ilvo.vlaanderen.be).
National Project: "Development and demonstration of a species-selective electro-
shrimp trawl for the brown shrimp fishery with the focus on the reduction of discards
and the environmental impact" ["PULSKOR" (project number VIS/05JE/01/DIV)]
The discarding practices associated with the brown shrimp fishery have been re
garded as a problem for many years. The poor selectivity of the small mesh nets used
produces very high amounts of unwanted bycatch. Consequently the implementation
of adequate selectivity enhancing measures should result in both ecological and
commercial improvements.
This national project was set up to investigate the potential of electric pulses as a
means to develop a speciesselective electroshrimp trawl. This new type of fishing
gear focuses on the reduction of unwanted bycatch, the reduction/elimination of bot
tom contact and the improvement of catchquality.
Contact: Bart Verschueren (bart.verschueren@ilvo.vlaanderen.be)
National Project: Evaluation of climate change impacts and adaptation responses for
marine activities (CLIMAR)
The North Sea Ecosystem is characterized by high productivity and highly diversified
habitats but also by an intensive use. As a consequence the vulnerability of the ecologi
cal, social and economic community formed by the North Sea is high (in terms of risk
on damage) for climate change. This calls for a sustainable approach when address
ing climate change issues in our North Sea.
Research and modelling will be carried out to differentiate the primary impacts of cli
mate change from the natural evolution at the North Sea scale. These primary im
pacts include sea level rise, increased storminess, possible increased rainfall, erosion,
temperature changes, salinity, etc. Then secondary impacts of climate change both on
the ecological system of the North Sea as well as on socialeconomic activities will be
assessed. Two extensive casestudies (coastal flooding, fisheries sector) have high ex

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trapolation potential towards the global North Sea environment. Adaptive measures
will be formulated both for the ecosystem as well as for the other marine activities.
Based on indepth application for the two above mentioned casestudies, an evalua
tion tool will be developed to assess the impact of these measures according to the
principles of sustainable development. Using parallel integrated assessment and pol
icy & legal evaluation, recommendations will be formulated towards North Sea future
policy. ILVOFisheries will be responsible for the development of the impacts of cli
mate changes on the fisheries sector, the development/evaluation/extrapolation of
different scen

ario s and adaptation measures for the Belgian fleet, and the formula
tion of a series of recommendations.
Contact: Els Vanderperren (els.vanderperren@ilvo.vlaanderen.be)
National Project:"Outrigger II"
The ILVOinstitute was asked by the "Belgian foundation for sustainable fishery de
velopment" to analyse and study the outrigger fishing method as a feasible and eco
nomical alternative for the beam trawl fishery.
Although the results of the "Outrigger I" project were very promising, it should be
taken into account that the fishing method by means of otter boards is quite complex
with respect to rigging and preparation involved and demands quite a lot of expertise
from the skipper and crew in order to be made profitable.
In order to inform the Belgian beam trawl fleet accordingly about the "outrigger
system" and to offer the possibility to switch over to this gear either depending, a
followup project "Outrigger II introducing outrigging with otter boards fishing in
the beam trawl fleet with the main objective to reduce fuel consumption".
Contact: Els Vanderperren (els.vanderperren@ilvo.vlaanderen.be)
19.2 Canada
Fisheries and Marine Institute of Memorial University of Newfoundland
Longlining through the Ice:
Winter longlining for Greenland halibut (turbot) is continuing in the Baffin Island
Region of the Canadian Arctic. Gear developments and operational techniques are
being refined and taught to the Inuit. Catch rates are now commercially viable but
developments in handling, processing, and export are still ongoing.
Contact: Philip Walsh (Philip.Walsh@mi.mun.ca).
Low Profile Trawl for Northern Shrimp:
Earlier results using a multilevel trawl revealed strong variation in the vertical den
sity distribution of shrimp in the mouth of conventional trawls used in Newfound
land and Labrador waters. The results lead to the subsequent design and flume tank
testing of new lowprofile wideopening trawl designs for both the inshore and off
shore fleets. A fullscale prototype has been constructed for the inshore region and
will be tested this summer.
Contact: Harold DeLouche (Harold.DeLouche@mi.mun.ca).

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Seabed Friendly Shrimp Trawls:
Design and testing is currently underway on several modifications for offshore
shrimp trawls to reduce their downward footprint on the seabed. Several models are
being tested in the flume tank and sea trials are expected later this year.
Contact: Harold DeLouche (Harold.DeLouche@mi.mun.ca).
Cod potting:
Thirty pots were given to 6 harvesters to use during their commercial operations in
2007. These harvesters fished from Sept to Nov with as much as 4050 lbs harvested in
nine pots. On November 23, 2007 a demonstration was held in Petley, Newfoundland
where individuals could come and look at pots during fishing operations. Govern
ment groups, fishing company representatives and harvesters attended. Pots will re
main with harvesters for the 2008 season with continued demonstrations. A
professionally produced promotional video is currently in development.
Contact: Philip Walsh (Philip.Walsh@mi.mun.ca).
Escape Mechanisms in Snow Crab Traps:
Based on the results of earlier experiments, escape mechanisms were introduced into
the commercial snow crab fishery on an experimental basis in 2005, 2006, and 2007.
Catch data continues to show that installing mechanisms around the bottom of the
trap results in reduced numbers of undersized crab being caught and discarded. The
program has been expanded and a total of 36 harvesters in 25 communities will
evaluate during the 2008 season. A professionally produced promotional video is
currently in development.
Contact: Paul Winger (Paul.Winger@mi.mun.ca).
Plastic Barriers in Snow Crab Traps:
The objective of this study was to examine the feasibility of using plastic barriers (i.e.,
collars) to reduce the incidental capture of white snow crab in the summer commer
cial fishery in Crab Fishing Area (CFA) 19 located in the southwestern Gulf of St.
Lawrence. Secondary objectives included an examination of the reduction of soft shell
and sublegal hard snow crab. Catches in traps fitted with 12, 18, and 24 cm high col
lars were compared along with catches in noncollared traditional and small mesh
(control) traps. It was concluded that plastic collars are not a suitable barrier to soft or
white shell snow crab; however they did prove to be effective at reducing the inciden
tal capture of undersized snow crab.
Contact: Wade Hiscock (Wade.Hiscock@mi.mun.ca)
Fisheries and Oceans Canada
Neutrally Buoyant Rope:
Experimental rope with a specific gravity close to that of water was monitored for its
ability to avoid turtle and other marine animal entanglements during the 2007 whelk
pot fishery in NAFO Subdivision 3Ps. The rope was also examined for overall fishing
effectiveness. During this year's project, no turtle or large marine mammals were en
tangled, nor sighted by the observer, in the area of the St. Pierre Bank. The sample set
was relatively small considering there were three observed fishing trips on one vessel
from August 12 ­ September 10, 2007. Catch rate differences were not significant and
the rope handled as well as the harvester's regular polypropylene rope.

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Contact: Judy Dwyer (Judy.Dwyer@dfompo.gc.ca).
19.3 Denmark
Activities in 2007 have mainly been embedded in nationally coordinated projects,
with particular focus on selectivity in commercial trawls.
A national project; SELTRA was funded by DFFE in collaboration with the Danish
Fishermen's Association to further improve selectivity of bottom trawl fisheries. The
project runs in 2006­2008 and gear from Nephrops and whitefish fisheries are investi
gated.
In 2007 several designs of species selective Nephrops trawls and codends including
T90 were tested in flume tank and during sea trials. Furthermore will, the properties
of a T90 codend be tested in flume tank using stereo vision technique. The projected
will be completed in 2008.
DIFRES participates in the EU project; DEGREE which aims at reducing the environ
mental impact of benthic fisheries. In 2007, pilot studies of a modified oyster dredge
were carried out in collaboration with the fishing industry. Further studies on the
selectivity of the dredge and its impact on the benthos will be investigated in 2008.
In order to achieve a better understanding of the selectivity process determined by
the relationship between fish morphology and mesh configuration, a multidiscipli
nary project (FISHSELECT) was initiated in 2006. It involves investigation of fish
morphology, testing of different mesh shapes and sizes in relation to different fish
species, and simulation of gear selectivity. Major activity in 2007 was data collection
for: cod, haddock, plaice, sole, lemon sole, turbot and nephrops. Concurrently with
the data collection was the methodology and tools improved and extended. The na
tionally funded project was completed in 2007. International collaboration with the
University of Tromsø (Norway) was initiated.
19.4 Faroe Islands
Kristian Zachariassen (krizac@frs.fo) and Bjarti Thomsen (bjartit@frs.fo)
Faroese Fisheries Laboratory P. O. Box 3051, FO-110 Tórshavn, Faroe Is-
lands.
Impact of scallop dredging
Investigations of the impact of scallop dredging on benthic communities began in
2005. The investigation is carried out on a scallop area that has been closed for scallop
dredging except for the years 1990­91. The size of the area is ca.100 km2 and is situ
ated north of the Islands. Samples by grab, triangular dredge and commercial dredge
as well as video have been taken all around the area. After sampling the area will be
open for commercial scallop dredging for about three years. After this period the area
will be investigated again and samples before and after dredging will be compared.
There has also been some experimental dredging carried out to see the direct effect of
dredging. The first result will be accessible by mid2009.
Groundgear development
Experiments to reduce the impact on the bottom from trawl groundgears have been
carried out in recent years mainly using underwater video observations. This work is
now integrated in the EU project DEGREE. Experiments with a combined plate gear
with rolling bobbins have been carried out on Norwegian research and commercial

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vessels in 2007. The final concept will be tested on the final DEGREE cruise onboard
on F/V "G. O. Sars" in October 2008.
Pelagic trawl research
A threeyear project has been initiated to study fish behaviour in pelagic trawls in
relation to water flow and geometry. This project will be undertaken in close coopera
tion with Icelandic and Norwegian institutes. The main aim of this project is to opti
mize trawl design with regard to water flow and fish behaviour. Trials have been
completed in 2007 and 2008, where flow inside large blue whiting trawls was meas
ured using ADCP technology. Preliminary results show that in trawls with long and
heavy codends there is a reduction of water speed just in front of the codend.
Size sorting grid for shrimps
In a project together with the trawl factory Vonin Ltd, Canadian scientists and
trawler owners in Canada and Greenland have experimented with size sorting grids.
These experiments were carried out in Canadian and Greenlandic waters.
A full scale version of the grid system was first tested in the flume tank in St. John´s
in April 2006. The first experiments with the size sorting grids were carried out in
Canadian waters in June 2006. These tests identified problems with clogging of
shrimps in font of the grid.
A new version of the grid system was tested in Greenland waters in December 2006.
These experiments showed a big reduction of small shrimps in the catch, from 160
shrimp per kilo to 130 per kilo. The grid tested had a bar distance of 10mm, which
was too wide, as too many medium size shrimps were lost.
This same system with a bar distance of 7 mm was tried in Greenland waters at the
end of April 2007. These tests showed that it was possible to sort out more than 50%
of small shrimps with this size sorting grid. Further experiments will be carried out to
try to make the sorting grid better to handle. Other bar spacing's will also be tested.
Effect of colour of gillnets for monkfish
In 2005 and 2006 experiments were made to see how the colour of gillnets affected the
fishing efficiency of gillnets for monkfish. A fleet of 200 gillnets with 5 different col
ours were tested. The fleets were sampled 21 and 31 times in 2005 and 2006 respec
tively. The fishing time was approximately 3 days each test at depths around 200m.
The colour of nets seems to have no effect on the fishing efficiency. In 2007 coloured
lines were tested and again the results showed no difference in the catch of monkfish.
Cod and Greenland halibut tagging
Since 1997, more than 26,500 cod have been tagged on various locations on the Faroe
Plateau. More than 7,900 cod have been recaptured, and stomach contents from more
than 1,800 of these fish have been collected. Analysis of this material provides valu
able understanding of the migration patterns and feeding behaviour of cod on the
Faroe plateau. Some of these results were reported to the ICES 2003 Symposium in
Bergen. A smaller scale tagging experiment on Greenland halibut and halibut was
initiated in 2002. Totally 399 Greenland halibut and 95 Halibut have been tagged and
of these 24 and 13 respectively have been recaptured.

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Effect of fishery on coral areas
Coral reefs in the Faroese area have been mapped using information from interviews
with fishermen and by underwater video observations. Underwater video recordings
will continue in 2008 and more detailed mapping will be undertaken. This informa
tion will be used in the discussion with stakeholders on preserving coral reefs. Three
different coral areas are now closed for trawl fishery to prevent damage to corals by
trawls.
Development of static gear
Research into the development of fish pots was initiated in 2005 with the aim to in
crease the efficiency and establish pots as a real alternative fishing gear for traditional
species (cod, haddock and saithe). Fish behaviour in relation to different design of
pots has been studied using underwater video observation. This work will continue
in coming years. In 2008 experiments will be conducted with low frequency vibration
for attraction of fish.
19.5 France
Ifremer
Nephrops selectivity (AGLIA 2006­2007)
The objective of this project was to provide a technological assessment and analyse
the data collected from sea trips onboard commercial boats in order to improve Neph
rops trawl selectivity in the Bay of Biscay.
Run in collaboration with the AGLIA and commercial fishermen, the project aims at
testing in three types of selective devices meant to reduce undersize Nephrops catches
(<9 cm) in commercial conditions: (i) square mesh panel fitted in the bottom part of
the extension; (ii) cylindrical bar Nephrops grid (13 mm bar spacing); (iii) 80 mm net
ting (to be compared with the 70 mm standard legal size).
Results achieved with square mesh panel fitted in the bottom part of the extension
Despite the low abundance indexes, the following results were achieved: (i) the es
capement rate remains quite significant (around 30%), though there is a high variabil
ity from one boat to the other; (ii) the commercial losses seem to be better controlled
with a reduced mesh size, though this remains to be confirmed as far as small low
powered vessels are concerned. With regards to this device, the results on escape
ments and commercial losses will be confirmed only after an extensive repetition of
the tests.
Results achieved with Nephrops grid
Almost no commercial size Nephrops escape through the bars of the grid. The average
escapement rate of undersize Nephrops (<9 cm) ranges is around 35%.
Results achieved with 80 mm codends
The tests at sea were completed from three different fishing boats. The escapement
rates seem stable from one boat to the other (around 30%).
The main goal is that by the end of 2008 one of the selective devices be adopted
commercially.

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Technology creep effects for Mediterranean bottom trawl fishery
Within the scope of CAFÉ project (6th EU framework program) this study aims to
examine the relationship between capacity and effort and hence fishing mortality for
Mediterranean demersal trawling fishery targeting hake as case study. Various tech
nical characteristics and their evolution of the trawling were collected over the last
10 years and matched to CPUE by GLM analysis. The initial conclusion of this study
shows the relationship of bollard pull measurement and door characteristics as cor
recting factors of the overall fishing capacity.
Experimentations on separator panel
Within the frame of the international project MEDICIS several studies have been car
ried out on hake (Merluccius merluccius) behaviour in the water column. For this pur
pose the effect of a horizontal separator panel fixed on a Mediterranean high opening
bottom trawl was tested in sea trials. Differences in species composition have been
observed but must be validated by multivariate analysis.
Shrimp fisheries
CHAMAD project in Madagascar
On request of the Malagasy Aquaculture and Shrimp Fisheries Syndicate, Ifremer
have conducted various studies investigating ways to reduce fuel consumption and
improved selectivity, assess impact, and provide training courses. Thus, in 2007, the
fisheries technology team trained the Malagasy Fisheries Commission officers in the
use of turtle excluder devices (TED) and bycatch reducing (BRD) devices. They also
took part in a TED validation trip onboard a Malagasy shrimp trawler.
Workshop on TED in Gabon
On demand of NOAA, the laboratory took part in a working group, hosted in Gabon
in September 2007, on introducing TED (Turtle Excluder Device) techniques in
shrimp trawl fisheries. This gave rise to many fruitful exchanges with the local com
mercial fishermen and the Civil Service officers. On this occasion, the results of tests
conducted in other parts of the world (USA, Nigeria, Madagascar, and French Guy
ana) were presented to the attendees. The meeting was followed by a demonstration
of the correct installation of TEDs onboard trawlers. Finally, some practical work en
abled the attendees to master the use of the selective device.
Workshop on brown shrimp fishery selectivity in French estuaries
In October 2007, Ifremer fisheries technology laboratory invited some thirty fisher
men currently fishing for brown shrimp. The technologists demonstrated scale mod
els of several selective trawls that fishermen already use. They appreciated very
much the fact of visualizing the gear shown in the flume tank and the possibility of
discussing selectivity improvements. The aim was to define and validate the various
models that will be tested at sea so as to assess their selective performances, more
particularly in terms of fish bycatch escapement.
ITIS-SQUAL: Pots, traps, and improvement of quality
Motivated by the need for competitiveness, in Brittany a project started on 1st May
2007 (duration 3 years). It aims to develop fish pots and Nephrops trap fishing tech
niques, and on improving the quality of the catches compared to trawl caught fish
and Nephrops. In June 2007, a workshop organised at Ifremer (Lorient) flume tank was
attended by fifteen fishermen and tests were conducted on various current traps and

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pots with a presentation on the state of the art about these fishing devices. The objec
tive was to define the first specifications of traps and pots adapted for use in the Bay
of Biscay. Novel concepts of fish pots are currently being developed in partnership
with the company Le Drezen and will be tested at sea in 2008 and 2009.
Regarding Nephrops traps, preliminary trials have been carried out in the south of the
Bay of Biscay with Scottish type creels, at depth ranging between 100 and 600 m; the
yields (kg per trap) are comparable to those obtained in Scotland. Collapsible proto
types are being developed in partnership with Le Drezen.
Experimentation on fish pots in the Mediterranean Sea
To provide Mediterranean small scale fisheries with less impacting techniques than
static or towed nets, the implementation of fish pot technique has been studied by
Ifremer since the 90's. The actions completed up to now have mainly consisted in
simple technology transfer to the fishermen as was done for Norwegian lobster and
deepwater shrimp traps. Since 2005, Norwegian collapsible pots have been tested for
fish on the continental slope between 100 and 600 m. Several technical modifications
have been tested so that they can be adapted to the fleet characteristics (vessels less
than 15 m LOA) and fishing conditions (depth, hard bottom, current). Problems were
experienced with target fish behaviour, pot stability, choice of material type and net
ting colour, scavengers, competition. Last year, an experiment began in cooperation
with fishermen organisations with 3 types of fish pots to target Sparus aurata in la
goons and coastal waters.
DynamiT software
Several licences of the software were sold during the last six months of 2007: five to
North Africa, one to the Netherlands and, very soon, one to IMARES Institute, one to
Spain, and finally three licences were placed at the disposal of representatives of fish
eries local committees so that they maybe able to carry out the project on energy sav
ings, managed by Ifremer.
Necessity project ­ Integrating selective devices in DynamiT simulation tool
As part of the EU Necessity project, new functionalities were added to DynamiT
software. It is now possible to simulate the mechanical behaviour of a selective grid
along with the various netting panels supporting the grid, which constitute the selec
tive device. It is also possible to simulate square mesh panels and separating panels.
Particular attention was paid to the ergonomic aspects of the application. Thus, for
instance the user can assess the angular positioning of the grid as a function of the
design of the device.
EU-DEGREE ­ Assessing the bearing stress of trawl doors on the seabed
The aims of the project are (i) to develop new fishing gears and techniques having
less impact on benthic habitats; (ii) to assess the possibilities of reducing the physical
impact along with the negative effects on the benthos; (iii) to assess the socio
economic impact of the modifications versus other alternative management steps.
Ifremer is involved in the development of novel bottom trawl components generating
no or hardly any impact on the benthic habitats (doors, groundropes); these devel
opments require flume tank tests, numerical simulations and tests at sea.
At the beginning of 2007, several techniques were tested in Ifremer flume tank in
Boulogne sur Mer, to assess the reaction force generated by trawl doors on the sea

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bed. A first series of data was collected from the tests conducted on three types of
doors studied according to several angles of attack. The results achieved have been
used to validate a theoretical model designed to calculate the reaction force generated
on the seabed by the doors, according to the fishing conditions. The theoretical model
was validated at sea last summer.
Energy savings
Regarding the coordination of the French Governments plan of action in terms of en
ergy savings, and in order to comply with the French Fisheries Prospects Scheme,
Ifremer fisheries technology lab is in charge of the coordination of national projects
on fuel savings, in conjunction with the industrialists and commercial fishermen.
A symposium on the subject was hosted in Lorient, in October 2007, on the occasion
of Itech'Mer Annual Fishing fair. Organised by an Ifremer technologists, the sympo
sium dealt with all the different issues on this topic. Some solutions were put for
ward, mainly regarding the design of fishing boats (shape, length, displacement,
propeller), the engine (alternative fuel), and fishing gears (trawls, nets). The economic
aspects of the problem were also approached, and the information collected from the
fishermen was distributed.
Furthermore, a project was started in cooperation with the Brittany fisheries regional
committee : two representatives, supervised by Ifremer fisheries technology lab, have
started a fuel efficiency project which consists of simulating with DynamiT tool some
practical cases of trawl optimisation so as to provide solutions towards energy sav
ing. The results were validated at sea and more tests will be carried out in 2008.
19.6 Germany
Institute of Baltic Sea Fishery
Alter Hafen Süd 2, 18069 Rostock (http://www.vti.bund.de/en/institutes/osf/)
Contact: Jens Floeter, Bernd Mieske, Harald Wienbeck, Christopher Zimmermann
NB: The Institute for Fishing Technology and Fishery Economics (IFF), Federal Re
search Centre for Fisheries, Hamburg was formally dissolved in 31 December 2007.
The IFF was reorganized into five departments, which are working in the areas of
environmental effects of fishing gear, fishing technology, hydroacoustic methods, as
well as fisheries economics. The group working on environmental effects of fishing
gear and fishing technology is now part of the Institute of Baltic Sea Fishery, Rostock.
The other groups are now part of the Institute of Sea Fisheries, Hamburg. The re
maining three federal fishery institutes are now affiliated to the new Johann Heinrich
von ThünenInstitut, Federal Research Institute for Rural Areas, Forestry and Fisher
ies (vTI, http://www.vti.bund.de).
Selectivity of flatfish trawls in the North Sea
Contact: Harald Wienbeck (harald.wienbeck@vti.bund.de)
The present fishing effort regulation for bottom trawls in the North Sea (EU 40/2008)
reduces the fishing effort with bigger codend mesh sizes (> 100 mm mesh opening) to
86 fishing days per year. The aim of this technical measure is the protection of the
weak cod stock usually harvested with this mesh opening. With the smaller mesh
sizes (70 to 90 mm mesh opening) a fishery targeting flatfish is allowed with 184 fish
ing days per year. This regulation has lead to a shift towards smaller mesh sizes in
North Sea commercial fisheries. This is backed by the fact that currently the fishery

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for cod is not economically feasible and that therefore fishermen are now concentrat
ing on flatfish (with the prescribed smaller mesh opening). As a consequence this has
lead to high discard rates of all fish species on the fishing grounds, which is detri
mental to stocks. A commercial fishing trip on board a German vessel was conducted
and demonstrated the high discard rates for the target species.
In the framework of the selectivity investigations carried out reductions in discards
were found when using codend meshes with larger mesh opening. Whereas in the
small mesh reference codend with 80 mm mesh opening 47% of the total catch of
plaice had to be classified as undersized bycatch, in the experimental codends with
120 mm mesh opening only 7% and with 130 mm mesh opening only 3% was dis
carded. On the other hand however, the increased codend mesh sizes gave subse
quent high escape of marketable plaice. By weight these losses equated to 18% with
120 mm codend mesh opening and 28% with 130 mm codend mesh opening.
Catch efficiency of experimental trawls in the Baltic
Contact: Bernd Mieske (bernd.mieske@vti.bund.de)
Experiments with a topless trawl (reduced upper layer) were conducted to design a
flounder trawl, which minimized the catch of cod. Comparisons between stern trawl
ers and side trawlers revealed differences in selectivity, but generally, a reduction in
cod catch around 85% was achieved with the topless trawl. However, this was also
accompanied with a loss of the target species (flounder) when fishing with the stern
trawler, while the opposite was true for the side trawler. Further modifying the de
sign to improve its performance is currently underway with the help of newly avail
able sensors.
Catch efficiency of set net and cod pots for Baltic Cod
Contact:
Bodo
Dolk
(dolk@fischumwelt.de
)
and
Jens
Floeter
(jens.floeter@vti.bund.de)
In the Baltic Sea coastal areas of Germany bycatch of birds and mammals in gillnet
fisheries for cod is seen as a problem. Therefore, a series of small scale feasibility
studies were conducted with the intention to, if possible, fully or partly replace the
gillnet fishery with cod pots:
2003­2004: "Investigating the catchability of fish traps in the area of the artificial
reef `Großriff Nienhagen'...." joint project by Landesforschungsanstalt für Land-
wirtschaft und Fischerei Mecklenburg-Vorpommern, Germany, and Fisch und Umwelt
M-V e.V.
In the Baltic Sea coastal area, 6 "Stuckitraps" and one prototype cod pot (double
chamber, 30mm, 10mm mesh opening) were deployed. The Stucki trap was deployed
without bait while the trap was baited with either sandeel or herring. The cod pot
caught almost exclusively cod while the Stucki traps, caught six additional fish spe
cies including eel, as intended. There seemed to be a negative correlation between
cod and eel catches within a Stucki trap. Setting the pots close to the bottom caused
problems with algae and jelly bycatch, and therefore investigating catchability with
pelagic pots is planned for the future.

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2005­2006: "Increasing the fisheries value of coastal areas...". Joint project by
Landesforschungsanstalt für Landwirtschaft und Fischerei Mecklenburg-Vorpommern
and Fisch und Umwelt M-V e.V.
Stucki traps and 8 cod pots of 7 different designs, incl. pots from the Norwegian
REFA Froystad Group, were deployed for 8 months and markrecapture experiments
were conducted. Cod catches from the pots in the period MayAugust were higher
than later in the year. Eel was the main species caught by the Stucki traps. In total
around 20 cod pots were deployed in single and also as strings. This small scale ex
periment (total cod catch < 500kg) with a limited number of cod pots confirmed the
results of the previous project. Additionally, good mesh selection properties were
demonstrated. Defining the optimal deployment depth, optimal baiting strategy ­
especially during the summer with high water temperatures , and pot design re
main.
2006: In August, the Federal Research Centre for Fisheries conducted a research
cruise with RV Clupea to compare the cod catches of gillnets and cod pots. 50 gill nets
(2000 m) and 12 pots (Norwegian type) were compared. In total the pots caught 15kg
cod; the nets caught 712kg cod, i.e., a factor of ~ 50.
2007­2008: Joined project by Bundesamt für Naturschutz and Fisch und Umwelt M-V
e.V.
Five commercial fishermen were equipped with a limited number of cod pots, which
were deployed as strings. The first results confirmed higher catches in summer than
in winter, but at generally too low levels to be economically feasible. There is a joint
initiative between vTI, BfN and Fisch & Umwelt e.V. for a larger scale project, which
aims at a more active involvement of commercial fishermen, increasing the number of
pots and enhancing their catch efficiency in cooperative trials.
Discard ban / Landing obligation - Pilot Study
Contact: Dr. Christopher Zimmermann (christopher.zimmermann@vti.bund.de )
In 2008 a pilot study to investigate the feasibility of a complete landing obligation for
all species and its advantages and disadvantages for fishery, science and manage
ment on a mediumterm began. The project has started with the North Sea fisheries
and the Baltic Sea fisheries will be included in due course.
The main objectives of this project are to give a reduction (or as far as possible pre
vention) of discards in the commercial fisheries. This will result in the better utilisa
tion of resources and the reduction of uncertainties in estimates of fishing mortality,
which in turns improves the quality of the scientific stock assessment. The other ob
jective is to strengthen the responsibility given to fishers as a step towards co
management. The final objective is a simplification of existing rules, which results in
a reduction of work for control and enforcement inspection authorities. The stability
of rules is aimed for (> 2years, compared to 1 year as typical at present), which would
result in better longterm planning opportunities for fishermen.
This is very much seen as an alternative solution to effort management. For selected
fleets, the outlined management approach might be better (to implement, to control,
to communicate) than present management systems or effort management systems
increasingly implemented in the EU. Therefore, it can result in an increase of fairness
in the competition between fishermen. Additionally, this concept will be beneficial
for those fisheries, which have already reduced capacities significantly during the last
years in accordance with the EUstrategy (e.g. Germany and Denmark).
The Key elements of this study are:

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i )
Landing obligations ­ All caught marine animals, including undersized
fish and nontarget species (with exception of jellyfish) have to be re
tained onboard and landed. If TACspecies are caught, all of these are
counted against the TAC (undersized and marketable).
ii )
Management ­ The regulation of fishery will be performed (at the final
stage of the project) solely based on a) TACand quota measures and b)
the setup of permanent and timerestricted protection areas for spawn
ing aggregations. Both measures are comparatively simple to control.
iii ) Suspension of technical measures ­ In return, most of the implemented
technical measures and the days at sea regulation will be suspended. As
a matter of fact, technical measures are increasingly complex, difficult to
control and expensive to be implemented by fishermen. A multiannual
stability of regulations is aimed at.
iv ) Scientific Programme ­ The study is monitored by scientists, who inves
tigate biological (onboard and market sampling), as well as socio
economic aspects.
v )
Possible extension: It may be necessary to counteract a fishery which be
gins to target juvenile fish (if this develops) and at the same time in
crease the incentive to reduce illegal (in this study) discards. While
minimum landing size will be omitted by all means, a minimum market
ing size could be introduced, where individuals below a given length
are not allowed to be sold for human consumption and have to be dis
posed via carcassprocessing plant (costcovering, but not profitable).
Approach
This study is built with two parts, which should be implemented simultaneously but
with different fisheries/participants: The first part is an intermediate step toward a
change of management strategy. A fishery with proven low discard rates will land all
discards within this study. This will demonstrate that for some fisheries a landing
obligation is applicable with a minimum of legislative and technical effort. The intro
duction of a discard ban for such "clean" fisheries has been submitted to the EU. Pro
ject partner for this part of the study is "Kutterfischzentrale Cuxhaven" and its saithe
fishery in the North Sea. The second part includes the introduction of a landing obli
gation for mixed fisheries with known discardproblems and simultaneously a sus
pension of a number of rules, as mentioned above. This goes far beyond the concept
of part one. Industry partner for this sub study will be the cod fishery of "EG
Burg/Fehmarn" in the Western Baltic and the cod and flatfish fisheries of the "Kutter
fischzentrale Cuxhaven" in the North Sea.
Working hypothesis
If more individual responsibility is given to fishermen, it is possible to implement a
sustainable fisheries management with fewer basic rules. In particular, a multitude of
technical measures is dispensable. It is also felt by the German authorities that a land
ing obligation/discard ban is technical feasible; acceptable for the fishing industry;
easier to control; and can be communicated to consumers as a way of demonstrating
good practice. The combination of a) the suspension of detailed technical regulations
and b) the introduction of a landing obligation will result in (after an implementation
phase): sustainable usage of fish resources; increased individual responsibility and
financial advantages for fishermen; and an increase of quality and quantity of data
used for stock assessments

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Underwater observation systems
Contact: Harald Wienbeck (harald.wienbeck@vti.bund.de)
The surface towed intelligent powered vehicle (STIPS II) with wireless transmission
of video and control signals is currently being revised to enhance its robustness and
observation capabilities. An initiative to reanimate an older 3D manoeuvrable towed
ROV System is underway. This ROV System would allow the observation of net ge
ometry and fish behaviour along the entire trawl.
Development of a long range pinger test device
Contact: Harald Wienbeck (harald.wienbeck@vti.bund.de)
Council Regulation (EC) No 812/2004 requires the mandatory use of acoustic deter
rent devices (pingers) to deter small cetaceans from bottomset gillnet or entangling
nets. However, the regulation does not provide detailed guidance on how the gov
ernmental enforcement bodies should control the correct usage and functioning of
these pingers.
The German authorities wanted to have a pinger control device that allows assessing,
whether a set net is correctly fitted with pingers and whether these are functioning.
Subsequently, there was the need to enable this control without the fishermen being
at place and retrieving the nets.
The device should allow:
· to test functionality of pingers at sea
· to count the numbers of pingers fitted to a set net
· to measure the distances between individual pingers fitted to a set net
(with additional help from GPS).
An initial Europewide survey of potential pinger test devices was not successful
with respect to the identified requirements. Manufacturers of similar devices such as
bat detectors were not interested in investing for device with a small market.
The prototype
A Danish company (ETEC Torben Roenne, Industrivaenget 8a, DK3300 Frederiks
vaerk, Denmark) agreed to enhance and further develop an existing control device in
cooperation with the Federal Research Institute for Rural Areas, Forestry and Fisher
ies (vTI), Institute for Baltic Sea Fisheries.
The prototype PG1101 Ping Go (ETEC) was equipped with a Hydrophone TC4033
(RESON), a Hydrophone protection cage and earphones. Tests with different,
cheaper, hydrophones did not give satisfactory results with respect to the detection
distance. It was thus further equipped with optical indicators (LEDs) for the detected
frequency of the signal and its field intensity.
The device was thus designed to display the detected pinger signal visually when the
signal was clearly identified. If the signal was too weak then detection was possible
via headphones.
The aim was to reach a detection distance of 400m because this would enable to hear
2 digital pingers simultaneously when they are correctly deployed (200m distance
between them).
The prototype PG1101 Ping Go has 3 modes of operation:

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1 ) The Click position is an envelope detector which monitors the high fre
quencies and converts them into something that is audible.
2 ) The Mixer position is a detector that functions somewhat like the other
but it also contains some information about the frequency of the test signal.
3 ) The position Audio is a listening position just to hear what is going on in
the water. It may also be useful for detecting analogue pinger signals of
around 10kHz.
Test setup:
The prototype of the new device was tested in 2007 / 2008 on three cruises (1. Danish
with Havörnen, and 2. German with Seeadler, Figures. 1 and 2). The tests were con
ducted with 3 pinger types.
Pingers were deployed on buoys and their functionality was tested from the vessels
Havörnen and Seeadler as well as from dinghies. Distances between the ships and the
buoys were measured by radar and GPS. Maximum detection distance was 900m for
analogue pinger types (Fumunda, Airmar) and 400 m for the digital AquaMark 100.
These detection distances were obtained from dinghies with engines turned off and
some distance away from the mother ships.
From the Danish inspection vessel Havörnen it was possible to detect the pingers
when only the auxiliary engine was running, but the detection distance was lower.
The same results were obtained with the German RV Solea while in harbour, how
ever, it was not possible to detect the pingers from onboard the German inspection
vessel Seeadler.
The optical indicators (LEDs) for the detected frequency of the signal functioned up
to a distance of 50m away from the pinger. When the noise level was too high or the
distance was larger than 50m, the detection was only possible via the headphones.
The field intensity indicators did not yet function in a satisfactory way, however they
are not required for the purpose of pinger control. Best results were obtained when
using the operation modus Mixer.
The tested device is a prototype and final modifications are still needed. This refers
especially to the waterproof design and the simplification of switches and visual indi
cations, and fine tuning the detection technique. A final version is envisaged to be
available in June 2008.
19.7 Iceland
Marine Research Institute Einar Hreinsson eihreins@hafro.is , Haraldur Ar-
nar Einarsson: haraldur@hafro.is , Ólafur Arnar Ingólfsson:
olafur@hafro.is .
Species selective demersal trawling
A separator trawl was tested in October 2007 for separating cod and haddock. A 64 m
stern trawler with 4000 hp main engine was used for the experiment. The vessels own
trawl was modified for the experiments. The trawl belly was cut 10.5 m behind the
bosom section of the fishing line and a divided trawl belly connected. The width of
the foremost part of the separator panel was 2/3 of the bottom panel. Cod, haddock
and saithe were measured, and other commercial species counted. An analysis was
made, investigating the vertical separation by fish length, depth, area (inshore, off
shore), diurnal variations (night, day, twilight) and mesh size in the separator panel.

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Another survey is ongoing at the same time as this FTFB meeting on the research ves
sel Árni Friðriksson. The plan is to film the trawl underwater and then make replicate
tows to measure how effective the cod and haddock separation in those two codends
and if there is any length based difference or different fish species composition.
Species selective Nephrops trawling
Last year a trial with grid in a Nephrops trawl was conducted. This grid, similar to the
Nordmøre grid used in shrimp fisheries, was designed to separate Nephrops and fish
in separate codends. A steel grid with 50 and 80 mm bar spacing's and a horizontal
separation panel were tested to separate fish from Nephrops in a demersal trawl. Two
codends were connected to the grid and panel. Almost all the Nephrops catch entered
the lower codend and most of the fish in the upper one. Fish separation varied among
species and fish sizes. The results show that a significant separation could be
achieved. There are also indications that by using a Nephrops grids in combination
with bigger mesh sizes in the fish codend and in the trawl belly, marketable fish
could be retained, while most undersized fish can be released. More trials are planed
this year on commercial fishing vessel.
Pelagic trawling in capelin fisheries
Information on trawl geometry and capelin behaviour was observed with underwater
cameras in a survey in 2007. In order to estimate the catching efficiency of this type of
pelagic trawl used in the capelin fishery, an evaluation of mean volume density for
capelin (in number per cubic metre) assumed entering the trawl, was compared with
recorded catch from the commercial fleet. Results showed low catching efficiency of
the capelin trawl. A new design of pelagic trawl for capelin fisheries is planned to be
tested later this year.
See in more detail (http://www.ices.dk/products/CMdocs/CM2007/Q/Q1207.pdf).
Sorting grids in blue whiting fishery
Development of a sorting grid system for blue whiting fishery is continuing. In last
years survey underwater filming was carried out to estimate how effective the sorting
grid was for releasing saithe and cod without lose of target species. The results were
clear, of the four grids tested none were effective but from the results a new design of
grids has already been made and will be tested and filmed in May this year.
Effect of hook size and bait size on size selectivity in the Icelandic longline fishery
Published results on the effects of hook and bait sizes on size selectivity of gadoid
fish have been inconclusive, probably partly due to a number of confounding effects.
To date, results from Icelandic waters are nonexistent. A designed experiment to
measure relative selectivity of cod and haddock for different hook and bait sizes will
be conducted in 2008. Several trips will be conducted throughout the year.
Development of pot fishery in Iceland
Within the last few years a trials has been carried out with large traps. They have
been used near coast inside fjords and bays, in relation to sea farming of cod and
haddock. Ina few of the trials, the small pots used for catching cod as well been done.
There is a growing interest in Iceland in this fishing method both in relation to fish
farming and commercial fisheries on a larger scale. An application for funding to test
traps and pots on a larger scale is being formulated and if funding is secured will be
gin later in 2008.

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19.8 Ireland
Dominic Rihan, Bord Iascaigh Mhara, Ireland, rihan@bim.ie
EU Degree Project
BIM carried out two series of flume tank trials with model doors to identify the char
acteristics which potentially allow the doors to be operated with lower seabed reac
tion forces. As it was not possible to make the doors lighter, reduced weight and
hence reduced reaction force was simulated by (i) increasing the towing speed, and
(ii) reducing the warp/depth ratio. Many different model doors were tested with suit
able trawls attached. This identified which doors worked well at different angles of
attack. All doors were tested when lifting off the seabed as this was considered to be
a more likely event of doors worked lighter on the seabed in practical fishing condi
tions.
A standard vee door was then tested in the flume tank, adjusting the warp and bridle
attachment points to correct poor behaviour when light on the seabed. This "re
balancing" using adjustments to the warp and bridle attachment points could be used
to correct other doors if necessary. Rebalancing involves altering the warp and bridle
attachments points in such a way that the desired angle of attack is maintained but
the centre of gravity of the door is not inside or outside the force lines of the warp
and bridle.
A series of three sea trials was carried out to examine these practical rigging prob
lems, and assess how the application of basic gear technology and training can be
used to help fishermen work existing doors better. These trials were carried out from
the ports of Greencastle in NW Donegal and also Castletownbere in Southwest Cork
and tested standard vee and Bison doors.
A project workshop was held in the flume tank in Hirtshals, Denmark in early March,
at which a demonstration of the "good" and "bad" door behaviour identified in the
earlier flume tank and sea trials was given to the project participants.
EU DEEPCLEAN project
BIM is currently involved in an EU funded study called DEEPCLEAN with the Ma
rine Institute, Galway, Ireland, CEFAS, Lowestoft, UK and Sea Fish Industry Author
ity, Hull, UK, which has the aim of recovering lost or abandoned nets in deepwater
gillnet fisheries > 200m and evaluating the effects of such "ghost fishing" by these lost
nets on these fisheries. In September BIM and CEFAS carried out a preliminary
analysis of whether it would be possible to fit an underwater camera system to the
net retrieval system being deployed. These trials were carried out in Norway and
were successful in that the camera could be mounted and orientated correctly but no
filming was carried out due to technical difficulties with the camera. A followup to
these trials is planned for May 2008 off the south west coast of Ireland on the Irish
vessel "India Rose". Following this survey a further 4 x 20 day retrieval campaigns
will be undertaken, covering Rockall, North, West and South Porcupine, Rosemary
Bank and areas to the west of Shetland. These surveys will be carried out over the
JuneSeptember 2008.
Environmentally Friendly Fishing Gears
Several sets of selectivity trials were undertaken during 2007/2008 as follows:

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1 ) Trials to assess the effect of reducing the number of meshes in the codend
circumference of standard nephrops trawls were carried out in Au
gust/September 2008. Two sets of catch comparison trials were completed
on board the Rossaveal based twinrig vessel "Maria Magdalene III", com
paring a standard 80mm x 6mm PE codend with 120 meshes in the circum
ference against an 80mm x 6mm PE codend with 100 meshes and 80
meshes respectively. The results showed reducing meshes round reducing
discards of whiting and haddock but a reduction in marketable nephrops
catches although there was a lot of inter haul variation making analysis
problematical.
2 ) Preliminary work with a flexible grid placed into the extension section of a
standard scraper trawl to release juvenile monkfish was completed in
January 2008. The grid used was designed by IFREMER in France. This
work was carried out on the Greencastle based single rig vessel "Cath
erineR" during a monkfish tagging survey being undertaken by the Irish
Marine Institute. Due to bad weather only a small number of tows were
completed but the results indicated that the grid did sort small monkfish <
34mm length. No handling difficulties on board the vessel were observed
with this grid. Further work is planned for later in 2008.
3 ) A project investigating the potential for incorporating flexible grids sys
tems into the codends of trawls for release of mackerel and horse mackerel
began in 2007, following approaches by industry. Extensive underwater
observations of two different grid designs was collected, allowing fine
tuning of the grids, as well as providing an insight into fish behaviour and
reaction to the grids. High levels of escapement were observed although
no assessment of escapement mortality has been carried out as early at
tempts using collecting bags placed over the grids were largely unsuccess
ful. This work is continuing.
4 ) Trials to generate selectivity data for a range of codends used in the Rock
all fishery began in April 2008. The selectivity of a standard 100mm x dou
ble 4mm PE codend will be compared to a 110mm x 4mm double codend;
a 100mm x 4mm double codend with a 120mm square mesh panel fitted 4­
7m from the codend; and a Russian style codend with 135mm x single
6mm codend with a 70mm x 4mm PE liner. This work is continuing and no
results as yet are available.
Environmental Management Systems
Working closely with Seafood Services Australia, BIM completed a pilot project in
2007 looking at the implementation of such a Seafood Environmental Management
System (EMS) in a number of pilot fisheries. These pilots involved individual fisher
men and 4 fishermen's cooperatives and following on from the work completed in
2007, an EMS manual has been produced and a target of implementing EMS systems
on 25 vessels has been set. Industry mentors have also been identified to assist fish
ermen work through the process. This work is being closely linked to looking at certi
fication/accreditation schemes currently being considered nationally.
Fuel Efficiency
As part of an EU project called "Energy Saving in Fisheries" (ESIF), which aims to
investigate potential technical and operational methods in addressing the need for
reducing energy consumption and associated costs in European fisheries, BIM in con

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junction with Engineer and Marine Surveyor Noel O'Regan of Promara Ltd have
been looking at a design for a "Green Trawler". A draft specification together with a
General Arrangement drawing describing a concept fishing vessel equipped for fish
ing with twinrigged trawls, single rig or as a pair trawler has been produced. This
concept vessel is designed to incorporate the highest level of efficiency available in a
practical form for use in the Irish fishing fleet. This concept, however, does not neces
sarily follow the design restrictions currently imposed by rules and regulations both
nationally and at EU level but strictly on design principles to maximise fuel effi
ciency.
New Fisheries
Two new fisheries were investigated during 2007/2008 as follows:
1 ) Exploratory fishing trials for deepwater rose shrimp () were completed in
August 2007 on board the Clogherhead vessel "Endurance". Extensive ar
eas off the west and southwest coasts of Ireland were explored but little or
no shrimp were caught.
2 ) Under a joint BIM and CEFAS project an assessment of the potential for
developing a fishery for hagfish in Irish and UK waters. The conclusion of
this study was that given the biology and stock structure in Irish and UK
waters it was unlikely a sustainable fishery could be developed.
Waste Management Project
In the latter part of 2007 and early 2008 following on from work carried out in 2006,
the Marine Technical Section set up a net recycling site in Tramore, Co. Waterford. A
net baling station has been installed at this site and over 20 tonnes of waste mono
filament gillnets, as well as salmon nets taken back from fishermen as part of the
Salmon Hardship Scheme have been successfully baled and transported to a Recy
cling firm, Petlon UK. Samples of PE netting have also been sent to Petlon for assess
ment as to whether this material can also be recycled into plastic products.
Gear marking
BIM recently have recently begun an EU funded project that aims to assess the cur
rent EU gear marking and identification regulations benchmark these against regula
tions in other countries and propose alternative designs that are practical, safe, cost
effective but also identifiable. A review of current regulations has been completed
and an inventory of available components for ear marking buoys has been made. Al
ternative technologies such as the use of RFID tags have been researched and its ap
plication to gear marking will be assessed in due course. This project is due to be
completed by October 2008.
Norman Graham, Marine Institute, Ireland, norman.graham@marine.ie
Monkfish Assessment and Tagging Programme
As a followup to work carried out in 2006 a followup monkfish assessment and tag
ging survey was completed in 2007. Two vessels were involved and allocated 14 days
charter each, these were the "Marliona" (SO 975), a 32.5m (LOA), 1243 Kw trawler
owned and Skippered by Cyril Harkin and the "Catherine R" (SO 956), a 30m (LOA),
741 Kw trawler owned and Skippered by Cara Rawdon. This fishery independent
survey is unique in that rather than providing a relative index of monkfish popula
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how the stock is biologically distributed. In addition to estimating the biomass,
monkfish have also been tagged in 2006 and 2007. This tagging exercise aims to
gather more detailed information on migration and diurnal behaviour.
Celtic Sea Cod Recruitment Survey
This project seeks to develop a collaborative Industry/Science herring and cod re
cruitment survey for the Celtic Sea stocks and to obtain data on migration patterns
and stock fidelity of cod through tagging experiments. Suitable areas and times in
which to measure the strength of incoming year class so that a recruitment index can
be built up over time were identified through discussion with industry. In addition a
new survey trawl was developed in collaboration with commercial net manufacturers
and BIM for the purposes of the survey. The trawl was designed with characteristics
that maximised the capture of cod and other demersal species but still adhered to the
recommendations SGSTS. Under the auspices of this proposal the survey design has
been developed and the trawl and associated hardware tested during winter/spring
2008. Surveys are planned to commence later in 208 subject to funding being made
available. In addition cod captured using short duration hauls have been tagged with
ribbon tags (~8000 fish) and a limited number (120) with electronic data storage tags
(DSTs) and tagged with high reward ribbon tags. Tagging was conducted in a num
ber of key areas, including the current Celtic Sea closed area, targeting both adult and
juvenile fish. This stratified approach will provide information on migration and fi
delity patterns of both juvenile (prefishery recruits) and adult fish as well as help
scientific evaluation of the current Celtic Sea area closures.
19.9 Netherlands
Wageningen IMARES (contact: bob.vanmarlen@wur.nl; tel. +31 317 48 71
81)
Reduction of cetacean bycatch in pelagic and fish bycatch in Nephrops fisheries EU-
project NECESSITY (NEphrops and CEtacean Species Selection Information and Tech-
nologY)
The project is finished and the final reports are being collated. A suite of discard re
duction devices were developed for the European Nephrops trawl fisheries. Acoustic
deterrents were developed for cetaceans in pelagic trawling as well as excluder de
vices showing potential to scare off the animals or release them from a trawl, but es
cape rates were still rather low and the conclusions were not definite, and therefore
followup research is recommended.
Development of fishing gears with reduced effect on the environment (EU-Project
DEGREE)
Additional experiments were proposed after questions were raised by ICES in 2006
concerning the use of electric pulses on species not caught that may come into contact
with the gear. Measurements were conducted on the generated stimulus in the facili
ties of the producing company VerburgHolland Ltd., and onboard the beam trawler
that fished commercially with the system MFV "Lub Senior" (UK153) to make sure
that the electrical stimulus of a pulse simulator to be used in the tank experiments is a
good match for the stimulus of the UK153 pulse trawl system in situ at sea. Tank ex
periments were then carried out at IMARES on cat sharks (Scyliorhinus canicula) using
this pulse simulator to appraise the survival, physical condition and behaviour of
these animals under stimulation. Further experiments are planned on cod (Gadus
morhua L.) and invertebrates. A more formal guidance structure from ICES than the

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present `ad hoc' topic and expert groups is needed and will be requested. The Dutch
fishing industry has plans to outfit a total of five vessels with pulse trawls and
winches likely beginning in September 2008 under derogation from the present ban
on using electricity in fishing of the EU (EC Reg. No 850/98 of 30 March 1988). This
involves substantial investments by the industry, which will partly be subsidized by
the Dutch government. Further implementation in the Dutch fleet depends on lifting
the EU ban, emphasizing the importance of a positive verdict from the scientific
community. Further work was also done on several other topics in the project, among
which adjusting the MAFCONSmodel to calculate the effects of new gear compo
nents on benthic invertebrates and relate their mortality with physical interactions on
various types of sediment.
EU-Project Energy Saving in Fisheries (ESIF)
A new project began in 2007 looking at potential energy savings in various segments
of the European fisheries, with participants from Denmark, Netherlands, Belgium,
France, United Kingdom, Ireland and Italy. This project aims at investigating poten
tial technical and operational methods to address the need to reduce energy con
sumption and associated costs in European fisheries. The study started with an
inventory of potential technical solutions and ongoing projects in the participating
nations. The economic performance of a number of selected fleet segments, using
data collected under the EU Data Collection Regulation (DCR), was analysed with
emphasis on the role of energy for individual fleet segments, a breakeven analysis
relating to fuel price, factors determining energy efficiency, the economic potential
for technological improvement, and scenarios for future outlook, particularly related
to possible development in the costs of fuel oil. Examples are given on a national ba
sis of research on reducing the drag of towed fishing gears, potential changes in gear
design, components and fish stimulation, as well as replacement by alternative gear
types, including static gears. In addition fishing vessel design and operation topics
will be addressed. The study will continue with an economic analysis of the merits of
these technical and operational changes.
National projects
A short study was conducted on the statistical problems associated with measuring
mesh sizes, and presented to an industry workshop. This work was done in relation
to the development of the OMEGAmesh gauge.
A project began in conjunction with industry on discard reducing techniques for
beam trawls. Three weeks of comparative fishing were carried out on FRV "Tridens"
in OctoberNovember 2007 using T90 and/or square mesh benthos release panels. A
major finding is that releasing benthic invertebrates can be achieved, but the penalty
is in many cases that marketable fish, particularly sole, are also lost to some extent.
The optimum solution is thought to be a panel that releases a fair amount of benthos
with only a relatively small loss in catch of target species and thus fishermen's in
come. Such losses might be compensated by an increase in days at sea as a bonus for
fishing more environmentally friendlier. The experiments will be continued in May
June 2008.
A number of new national projects were proposed by groups of fishermen in the Call
of March 2008 of the Dutch Fisheries Innovation Platform in which IMARES (together
with ILVO Ostend Belgium) plays a scientific guiding role. These proposals involve
the development of hydromechanical stimulation in beam trawling for flatfish, im
proving the catch rate on sole in fishing with outrigger trawls replacing beam trawls,

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and the optimization of a hydrodynamically shaped beam to replace the conven
tional cylindrical ones in beam trawling in order to reduce gear drag and fuel con
sumption. These projects, if granted, are expected to start after the summer of 2008.
19.10 Norway
Institute of Marine Research, Bergen
Unaccounted mortality of mackerel crowded and slipped in purse seine fisheries
Full scale survival experiments carried out in the North Sea in Aug/Sept 2006 and 07,
have for the first time revealed that the unaccounted mortality of mackerel (Scomber
scombrus) that have been exposed to crowding and slipping from a purse seine, may
be huge. In five parallel experiments, where mackerel was crowded until the fish
showed a panic reaction for 10­15 min, the mortality was monitored and compared to
that of an untreated control group. The mortality of the crowded fish was signifi
cantly higher than of the control groups. From 80 to 100% of the crowded fish died
within 2 to 6 days, while the mortality of the control groups varied between 0 and
46%. The experiments show that the mackerel is extremely sensitive to handling and
stress, and that the unaccounted mortality due to crowding/slipping in the purse
seine fisheries may be high.
Contact: Aud Vold Soldal; aud.vold.soldal@imr.no
Fish Welfare in Capture Based Aquaculture
In capture based aquaculture, wild fish are being held in net pens in order to supply
fresh fish with high quality throughout the year and thereby increase the value of the
catch, given a set boat quota. Welfare issues in CBA arise when handling stress and
adaptation costs to new environments are added to the capture stress, and the dura
tion of impact will increase dramatically contra traditional fishing. In spring 2007
fishing trials focusing on effect of swimbladder puncture on mortality, behaviour and
physiology have been conducted. Behaviour of cod (resting and acclimatization time)
in transport tanks and net pens has, for the first time, been quantified by use of elec
tronic data storage tags. Pressure tests of vacuum pumps onboard fishing vessels
used to move live fish from tanks to net pens revealed (coupled with data on swim
bladder healing) pressure reductions way in excess to repuncture cod swimbladder.
Preliminary data suggests that functionality of a punctured swimbladder is rapidly
restored, and that swimbladder puncture alone does not lead to longterm detrimen
tal chronic stress.
Contact: OddBørre Humborstad; Oddb@imr.no
Effect of gangion floats on bait loss and catch rates in longlining
Bait loss in bottom set longline by predation of scavengers such as bottom lice (am
phipods and isopods), crabs, hagfishes etc is a problem in the coastal fishery for cod
and haddock in northern Norway. By floating gangions 70 cm off the bottom, com
parative fishing trials showed a slight increase in cod catches, decrease in haddock
catches and reduction of flatfish and elasmobranch bycatch. Results may be explained
by less bait loss for floated longlines, higher visibility of floated baits, and species
specific differences in feeding strategies.
Contact: OddBørre Humborstad; Oddb@imr.no

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Reduce bycatch of king crab in the gillnet fisheries for lumpsucker
Trials with gillnets for lumpsucker which were equipped with a 70 cm high, fine
meshed panel at the lower part have been carried out. Compared to a standard gill
nets the bycatch of king crab were significantly reduced while the catch of lump
sucker only reduced by about 10%.
Contact: Dag Furevik; dag.furevik@imr.no
A new demersal survey trawl
IMR is working on a project with the objective to develop a new demersal survey
trawl. This two panel trawl is equipped with short bridles (15 m) and selfspreading
ground gear. Comparisons in the Barents Sea between the standard sampling trawl
and the new trawl indicates that the new trawl has lower efficiency for juvenile cod
and haddock, while the opposite was obtained for large cod.
Contact: arill.engas@imr.no
Development of midwater trawls for gadoids in the Barents Sea
Midwater trawling targeting gadoid fish has been banned in the Barents Sea since the
late 1970's due to high catch rates of juvenile fish. Due to increased concern about
bottom impact from demersal bottom trawling, research is carried out to verify if
midwater trawling techniques can be an economical and sustainable method for
catching gadoids. Low catch rates have been obtained with the midwater trawl com
pared to dermersal trawl carried out in the same area, mainly due to the difference in
distribution.
Contact: terje.joergensen@imr.no
The University of Tromsø, The Norwegian College of Fishery Science
Comparisons between traditional and mechanized de-hooking systems in coastal
longline fisheries
Experiments show that it is possible to use a simple device to dehook fish without
using the traditional gaff. Landed fish are hence without gaffmarks and quality and
outcome is improved. There are minor differences in efficiency between traditional
and the new technique, i.e. retention of fish with the new hauling system (known as
"automatic dehooking unit"). Fishermen claim that it is a great advantage during
hauling with reduced labour as no gaff is needed. Instead they can spend more time
in preserving fish quality. The results are reported in different presentations, reports
(in Norwegian) and via fisheries magazines. Further experiments with the automatic
dehooking unit will be carried out during summer 2008 on live fish landings from
the coastal longline fleet, targeting cod (Gadus morhua) and haddock (Melanogrammus
aeglefinus).
Improved retention of fish in the Norwegian mechanized longline (autoline) fisheries.
During 2006 and 2007 a system comprising a hauling well in the side of the vessel
was tested. The vessel used is one of the most modern Norwegian longliners, the 51
m M/V "Loran". Dehooking is made inside the well and the traditional gaff is re
moved during hauling. The idea behind the technology is to reduce incidental loss of
fish (outside the boat), to improve quality on landed fish (no gaffmarks) and to im
prove the comfort and safety for crew during hauling. In extreme weather conditions
the vessel can continue hauling the line with the traditional hauling hatch closed.

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During our experiments the focus was retention of fish, i.e. efficiency and reduction
of incidental loss of fish (and possible reduction in unaccounted mortality).
M/V "Loran" is currently the only vessel with this technology, which is a somewhat
simpler technical solution to the "moonpool" used on the M/V "Geir". The results are
reported in different presentations, reports (in Norwegian) and via fisheries maga
zines, including World fishing.
Results from two periods (autumn 06 and spring 07) show an increase in catch of 2 to
4% for cod (Gadus morhua), 6 to 10% for haddock (Melanogrammus aeglefinus) and 8 to
14% for Greenland halibut (Reinhardtius hippoglossoides) with the new hauling tech
nique. The results are accepted for publication.
Further experiments will be carried out during 2008 aiming at comparing a tradi
tional vessel to the vessel with new hauling method with focus on efficiency, fish
handling/quality and working conditions/safety for the crew during hauling.
Project Title: Size selectivity patterns in the North-east Arctic Cod and Haddock fishery
with sorting grids of 55, 60, 70 and 80mm
Sorting grids are compulsory for trawlers fishing for cod (Gadus morhua L.) and had
dock (Melanogrammus aeglefinus, L.) in Norwegian waters at the Barents Sea. Four dif
ferent sorting grids were tested onboard R/V Jan Mayen (64 m) during February
March 2007. The aim of the study was to determine the changes in selectivity parame
ters when increasing bar spacing from the compulsory 55 mm to 60, 70 and 80 mm. In
all cases, the codend used was a standard 135 mm codend. This study shows different
exploitation patterns on cod and haddock populations. The conclusions of the paper
are useful in order to help determining the optimal exploitation pattern for a certain
cod or haddock stock.
The results indicated that for haddock there is little variation in the selectivity pa
rameters when increasing bar spacing from 55 to 60 or 70 mm for haddock (2.7 cm
in the l50 while the SR is fairly constant around 5 cm). For cod, no differences were
found between the 55 and the 60 mm grids or the 70 and 80 mm grids, but the first
two differed from the latter. The mean l50 increases from 56.08 to 73.33 cm and the
mean SR from 7.46 to 14.28 cm when the bar spacing is increased from 55 to 80 mm.
The selection curves move to the right and tend to lose sharpness, and the 95% confi
dence areas increase gradually as the bar distance of the grid is widened. The rela
tionship between the l50 and grid bar spacing, based on this and previous studies, was
determined to be linear for both cod and haddock. The results are in a review proc
ess, Fisheries Research.
Further experiments on the importance of fish morphology on fish escape are
planned for 2008. In addition, the implications of using covered codend or paired
gear sampling methods for selectivity study purposes will be investigated.
SINTEF
Energy friendly Shrimp trawling
The development and testing of a new energy friendly trawl for fishing of shrimps
has been continued in the period during 2007­2008. A full scale trawl was con
structed and tested in a triple rig arrangement onboard a commercial trawler in the
Barents Sea. The fishing efficiency of the trawl showed to be poor with about 65­70%
of the catchability of the standard trawls towed by the vessel. Observations using
small mesh collecting bags showed that the shrimps escaped through the side panels

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and the larger meshers in the upper panel. An alternative design with more small
mesh in the upper panel has been constructed to solve this problem. More full scale
tests will be made to test this new design. The project has been funded by the Fish
eriea and Aquaculture research fund.
Model based surveillance of trawl systems
The submerged parts of the trawl systems can not be directly observed, and the
available measurements are often few and unreliable. To address this issue, SINTEF
Fisheries and Aquaculture are developing a state estimator based on a mathematical
model of the system. The mathematical model is used in a simulation running in par
allel to the real system. The simulation is thus able to improve existing measurements
in terms of both precision and update rate, as well as to provide information which is
not, or can not be, measured. The provided information may include any position
and velocity in the trawl system, such as trawl door orientation, wing spread and
wing positions, as well as e.g. information about the bottom pressure and symmetry
of the trawl. The model is improved and adapted to the actual system by using the
available measurements. This project is part of a project run by RollsRoyce Marine,
where the goal is to develop a control system for trawl winches which can take the
additional available information into account. Offshore Simulation Centre, Alesund is
also part of the project, responsible for the 3D visualization of the trawl system. Con
tact: KarlJohan Reite; karl.j.reite@sintef.no
Harvesting zooplankton by use of air bubbles
In recent years there has been increased interest in exploitation of marine zooplank
ton like copepods and krill. Trawls with very small meshes have a high towing resis
tance and problems with bycatch, and may not be suited for industrial harvesting of
such resources. Addressing this technical challenge is the goal of our project, where
we study the use of air bubbles to lift Calanus to the sea surface to be skimmed by an
oil spill recovery type skimmer, or to concentrate Calanus closer to the surface to be
collected by a trawl with reduced opening area. The air bubbles are released by a
sparger system towed at 40 m depth or less. The `lifting' can be achieved by two dif
ferent mechanisms, namely flotation and upwelling. Flotation means that air bubbles
attach to the Calanus body and lift it by buoyancy. Upwelling means that a lot of
bubbles are generated to induce an upward water transport, bringing everything that
naturally follows the water with it towards the surface. The project has included
laboratory studies of pure bubble hydrodynamics as well as high speed video captur
ing and analysis of interaction between bubbles and live Calanus. So far the upwell
ing mechanism appears most promising, although attachment and flotation of
individual Calanus has also been observed, and will be tested at sea in the summer of
2008.
Contact: Svein Helge Gjøsund; Svein.H.Gjosund@sintef.no
Triple trawls with asymmetric fastening of centre weights
Trawl systems with three nets are commonly used for prawn fisheries, and a widely
used configuration has four main wires connected to two trawl doors and two centre
weights, respectively. The centre weights are constructed with rollers to reduce tow
ing resistance. Asymmetric fastening of the main wires onto the weights has been
proposed to change the yaw angles and provide extra spreading forces on the
weights. The intention is to achieve a wider trawl system and increase the fishing ef
ficiency. Fullscale tests were performed with a commercial trawler at a water depth

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of approx. 260 metres, with symmetric and asymmetric fastening of the main wires.
Several forces and distances were measured, and statistically significant results
showed that asymmetry reduced the total distance between the trawl doors by 26
metres. The total distance between the trawl doors was about 180 metres. Contrary to
the intention, asymmetric fastening of the centre weights reduced the total width of
the trawl system.
Contact: Vegar Johansen; vegar.johansen@sintef.no
Optimization of bottom trawl gear with respect to energy consumption
Fundamental research has been performed to achieve more knowledge on hydrody
namic properties of net panels and rockhopper bottom gear, and improved mathe
matical descriptions of the hydrodynamic loadings will be developed based on the
experiments performed in the flume tank. Flume tank experiments with a trawl net
were carried out as well, and response forces were measured as a function of the
trawl opening's width and height. The hydrodynamic loading models will be verified
by comparing such experiments to numerical simulations with these new loading
models. A new computer tool for simulating net structures is being developed, and
will be used for this comparison. Model scale experiments with trawl door bottom
impact have also been performed, and these will form the basis for the development
of new structureseabed interaction models. In order to make such research results
available for daily operation of bottom trawls, a computer tool has been developed
for studying the effect of changes in the rigging of the gear. The latest models and
mathematical descriptions are included in the tool, enabling the fishermen to inves
tigate how changes in important parameters like weights, floaters, door sizes, net
mesh sizes etc. influence on the geometry and towing resistance. This computer tool
may help the fishing fleet to optimize the equipment to their current operation condi
tions. The project is funded by the Norwegian Research Council and The Norwegian
Fishery and Aquaculture Industry Fund.
Contact: Vegar Johansen; vegar.johansen@sintef.no
19.11 Spain
Institute: AZTI Tecnalia
Esteban PUENTE (epuente@suk.azti.es)
Fishing Technology related projects carried out at AZTI Fundación (Technological
Institute for Fisheries and Food; www.azti.es) by the Marine and Fishing Gear Tech
nology Research Area.
Field study to assess some mitigation measures to reduce bycatch of marine turtles in
surface longline fisheries (project Ref. No. FISH/2005/28A)
This project worked with fishermen to test hook and bait types in European surface
longline fisheries targeting swordfish in the Atlantic, eastern and western Mediterra
nean with the aim of assessing whether they reduce turtle bycatch. The trials were
conducted in collaboration with the fishing industry in the following fisheries:
· Greek longline fishery in the eastern Mediterranean,
· Spanish longline fishery in the western Mediterranean,
· Spanish distant water longline fishery in the southeast Atlantic Ocean,

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Two longlines were set each day, one with squid bait and one with mackerel bait, and
each with alternating magazines of J hooks, 0º offset 16/0 circle hooks and 10º offset
18/0 circle hooks. A total of 124 turtles were caught in the trials -- 9 leatherback tur
tles and 115 loggerhead turtles. More loggerhead turtles were caught in the Atlantic
and western Mediterranean (36 and 77 respectively) than in the eastern Mediterra
nean (2). Turtle bycatch was significantly affected by bait type. Turtles were consis
tently caught more frequently on squid bait than on mackerel bait, and 82% of all
loggerhead turtles were caught with squid. There was no significant difference in
turtle bycatch rates between circle hooks and J hooks, although there was an indica
tion that 18/0 circle hooks were less likely to be swallowed than J hooks or 16/0 circle
hooks and, in the western Mediterranean, that turtle catch rate on circle hooks was
slightly lower than on J hooks. Swordfish catch rates were not significantly affected
by bait type in any region. However, hook type did have an influence in the western
Mediterranean, with significantly higher catch rates of swordfish on J hooks com
pared to circle hooks. The size of swordfish caught was not affected by hook type, but
bait type did have an effect in the western Mediterranean, where larger swordfish
were caught on squid bait compared to mackerel bait. Effects of hook and bait on
other species caught during the trials as secondary target species or bycatch were also
monitored. Bluefin tuna catches were significantly lower on mackerel compared to
squid bait in the western Mediterranean.
Nephrops and Cetacean Species Selection Information and Technology (NECESSITY)
EC contract 501605
The overall aim of the project is to develop alternative gear modifications and fishing
tactics in collaboration with the fishing industry to reduce bycatches in the relevant
European Nephrops and pelagic fisheries without reducing significantly the catch of
target species. AZTI is involved in the part of the project aiming at the minimisation
of the cetacean bycatch, focusing in the VHO trawl fishery. After characterisation of
the incidental bycatch of cetaceans (levels of the bycatch, operational factors associ
ated with the bycatch, seasonality and geographical occurrence), the study has fo
cused in 2005 on the design and test at model scale of dolphin escape devices in the
flume tank. Tacking into account previous studies of dolphin behaviour inside a
trawl net, the escapement device has been designed with big diamond shaped orifices
in the upper part of the extension of the trawl net with overlapped small meshed net
ting covers, altogether with a rope barrier located at the same level of the net. During
2006, different configurations of the escapement devices have been fitted to a com
mercial trawl and tested in several fishing trials in the commercial fishery. Underwa
ter cameras were used to assess the hydrodynamic performance of the net, the
eventual dolphin escapement, as well as fish behaviour (target and non target spe
cies). The results of the trials shows that the escapement device designed do not affect
the behaviour of target species (hake) inside the trawl net. The video footages also
show that the escapement device provides an escapement orifice for dolphins in the
upper part of the net that can be open when pushed upwards from inside the trawl.
Unfortunately, given the low frequency of the dolphin bycatch occurrence, no en
counter of dolphins inside the net was recorded during the trials so the efficiency for
dolphin escapement still needs to be proven.
Development and testing of a semi- automated rod for the pole and line tuna fishery
(AZTI project ATM2006CAÑA_CIM).
The pole and line artisanal tuna fishery with live bait requires a large crew as it is es
sentially a manual fishing method manually. The aim of this project is to develop an

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automated rod prototype which can substantially reduce the manpower needed for
the fishing operation, as well as to minimize operational risks associated with hooks
and physical overeffort (back injuries). A first prototype has been designed, built and
tested in the commercial fishery during the summer tuna fishing in 2005. As a result
of the fishing trials with the prototype, several technical improvements have been
identified and defined in terms of technical specifications. Two more improved proto
types were built in 2006 based on the reviewed technical specifications. They have
been tested in the commercial tuna fishery in 2007 with success both in terms of re
duction of manpower for similar catching performance to the classic pole and line
manual operation and of increased safety during fishing operation.
Analysis of the acoustic spectrograms of tuna fishing vessels (AZTI project
ATM2006RUIDO)
Vessel noise is an important factor to be taken into account in the fishing performance
of artisanal tuna fishing vessels using trolling lines as well as pole and line with live
bait. This is to minimise fish avoidance to vessel as much as possible during fishing.
The objectives of the study are: to establish a standard procedure for the measure
ment of noise radiated by commercial vessels using hydroacoustic equipments; to
define the noise pattern of different categories of vessels; to define the noise charac
teristics that have an influence on fishing performance according to sound and vibra
tion sensitivity of tuna. Different measurement operations of commercial fishing
vessels were carried out along 2005, 2006 and 2007, building a database of noise re
cordings of the fleet. Noise recordings are processed to obtain sound pressure levels
and frequency spectral composition. The project is carried out in consultation with
technical staff that checks acoustically the fishing vessels every year by studying their
air radiated noise. The long term goal of the study is to be able to establish the un
derwater noise pattern of those mechanical deficiencies in the vessels detected by ae
rial noise recording.
Development of a fuel management system for improvement of the fuel consumption
pattern in fishing vessels
The main aim of the project is to improve the fuel efficiency in fishing vessels. In or
der to characterize accurately the pattern of fuel usage onboard, a complex consump
tion measuring system has been designed, capable of recording not only the fuel
consumption but also many other interesting variables, such as the wind force and
direction, the exhaust gas temperature, the rolling and pitch movements and the
speed among others. The information given by each sensor will be recorded every
second in a computer. This will allow calculating how much the fishing vessel con
sumes in each part of the fishing operation. The installation of the first measuring
system is being carried out and the same will be done in other three vessels during
the summer. As soon as the system is installed, analysis of the data files will be car
ried out so that possible improvements of the consumption pattern might be identi
fied.
Design and trial of a new trawl net to reduce fuel vessel consumption in the bottom
trawl fishery targeting multi-species in ICES VIIIabd
Thinner and robust netting materials are available in the market for the construction
of fishing nets that can reduce the drag of the trawl and hence improve the energy
consumption of fishing vessels. A modified design of a commercial bottom trawl net
has been designed and built with the half upper part of the trawl replaced by high
tenacity polyethylene netting except in the codend. Preliminary trials at sea have

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ICES WGFTFB REPORT 2008
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been carried out in 2006 to establish the working method for the assessment of the
hydrodynamic performance of the trawl system, its catching efficiency and the level
of fuel consumption of the towing vessel during fishing. The preliminary trials point
out that there is room for fuel consumption optimisation while maintaining similar
catch rates for the target species. Further improvements in trawl design and trawl
fishing system have been carried out in 2007 and modelled prior to trials at sea. Ex
perimental fishing trials are scheduled in 2008 to evaluate net geometry, catching per
formance, fuel efficiency and operation on deck.
Viability study on the potential to improve fuel efficiency in fishing vessels of the ap-
plication of renewable sources of energy (solar & eolian)
The trend to increasing fuel prices is one of the most serious threats that the fishing
sector has to face in the short term. This research project aims at studying the poten
tial of the use of renewable sources of energy (solar: photovoltaic plates; eolian: wind
vane layouts; sail assistance) to reduce fuel consumption on fishing vessels. The pilot
study focus on a trolling line type vessel, as these vessels have long running hours
over the course of the tuna season. The electric power generation of possible solar
plate and wind vane layouts has been calculated. Studies are being carried out to de
terminate the maximum sail area and describe the necessary changes so that adequate
stability is kept. Apart from estimating (or measuring in case of installing sails in a
prototype) the fuel saving achieved by the use of sails as an auxiliary power source,
the roll reducing effect of the sails will also be studied.
Technical and economical study on the potential fuel efficiency improvements of hull
and propeller modifications
When a boat is sailing at a constant speed, the driving force of the propeller is bal
anced by the force resisting motion. The main objective of this study is to evaluate the
suitability of changing the propeller and hull appendage designs in order to reduce
fuel consumption, either optimizing the propulsion or improving the hydrodynamic
characteristics of the hull. A classification in different groups has been carried out
among all the fishing vessels of the fleet attending to the hull design and the fishing
operation. A sample of several fishing vessels, representatives of each group, all the
possible modifications on the hull are being studied and designs of new propellers
are being looked at. Although many of the modifications studied will not be executed
during the course of this project, their improvement in fuel efficiency will be esti
mated based on naval engineering methods. Conclusions will be reached about the
potential of hull/propellers changes in the rest of the fleet after estimating (or measur
ing in those vessels where modifications will be carried out) the improvements in
terms of fuel efficiency achieved with each modification.

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ICES WGFTFB REPORT 2008
19.12 Scotland
Fisheries Research Services
Dave Reid (reiddg@marlab.ac.uk) for the FTFB team at FRS
Selectivity and other work in relation to Scottish Industry Science Partnership and
Scottish Government
FRS are running an ongoing programme linked to industry summaries in the table
below.
Funding General
Description
Conservation Area Vessel Survey
Driver
Type
Date
SISP
Selectivity of North Sea
Reduce whitefish
North
Twinrig
14­28
Nephrops gear using 100­
(cod, haddock and
Sea
vessel
April
(06/08)
120mm square mesh panels.
whiting) discards
2008
in mixed

Nephrops/whitefish
Aim identify mesh size for
fisheries.
SMP positioned in the taper
which will provide a
compromise between
allowing sufficient juvenile
cod, haddock and whiting to
escape while retaining viable
quantities of marketable fish
and Nephrops.
Method Selectivity of up to 3
configurations of SMP in two
different codends made from
netting of 80mm and 90mm
single twine. SMP at end of
tapered portion of net within
the legal maximum distance
from the end of the codend.

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ICES WGFTFB REPORT 2008
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Funding General
Description
Conservation Area Vessel Survey
Driver
Type
Date
SISP
Effect on selectivity of
Reduce discards
West
1. >500hp
3­12 June
(07/08)
different mesh sizes and
of juvenile fish in
Coast
Nephrops
2008
positions of square mesh
gears used to
twinrig
panel for vessels of large and
target Nephrops
vessel
small horsepower


2. l50­250
Aim improve selectivity for
hp single
juvenile fish in Nephrops
trawl
gears. Anecdotal evidence
vessel
smaller low powered vessels
more selective than higher
power vessels. Method
Large SMP for range of
different mesh sizes
(>140mm) tested on a larger
powered (>500hp) Nephrops
twin trawl vessel. Positioning
the panels at the end of the
trawl's tapered section. Also
tested on lower powered
vessel to assess effectiveness
at reducing discards but still
maintaining Nephrops
catches.
SISP
Selectivity of Nephrops gear
Reduce whitefish
North
Low

(08/08)
using square mesh panels on
(cod, haddock and
Sea
powered
Early
small vessels on North Sea
whiting) discards
(Inshore)
twinrig
August
inshore grounds.
in mixed
vessel
2008

Nephrops/whitefish
Aim identify the mesh size
fisheries
for an SMP positioned in the
taper which will eliminate
discards of cod, haddock and
whiting while retaining viable
quantities of Nephrops
Method measure selectivity
of up to 3 configurations of
SMP with an 80mm codend
on a lowpowered twinrig
trawler.
Method
SISP
Trial to reduce cod bycatch by
Reduce mortality
North
Whitefish

(09/08)
modification of a commercial
on cod, and
Sea
twinrig
23 June ­
whitefish trawl to incorporate
particularly
vessel
4 July
large meshes in the lower
juvenile cod
2008
wings and belly sheet
Aim To modify an existing
whitefish trawl by inserting
very large diamond mesh
netting panels into the belly
sheet and lower wings to
allow an escape route for
juvenile cod but still retaining
other commercially important
ground fish species.

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ICES WGFTFB REPORT 2008
Funding General
Description
Conservation Area Vessel Survey
Driver
Type
Date
SISP
West of 4 ­ Windsock
Evaluation of
NW of
Whitefish
10­19
0?/07
Aim to evaluate the effects
closure effect
Scotland
single
March
of windsock closure on catch
trawl
2008
rates within and without the
vessel
closed area
Method ­ The study will use a
charter vessel which has
worked the windsock and
adjacent area prior to closure
and has diary records of this.
The survey will then resample
these tows to establish catch
rate changes
SISP
GOV twinning.
Confidence in FRS
North
>1000hp
19 May1
0?/07
Aim ­ to investigate the
survey trawl
Sea
Whitefish
June 2008
potential for twin trawling the
especially for cod
twinrig
GOV with a similar sized
vessel
commercial net. To carry out
trials to illustrate the relative
catch rates of the two nets
Method ­ 10 days trials to
establish technical feasibility
of twinning the two nets,
followed by 10 days of tows
on IBTS and other stations
SGMD
Nephrops size selectivity using
Improve
North
>500hp

(SLA)
grids, meshes round or
selectivity for
Sea
Nephrops
Early
square mesh belly panels.
Nephrops
twinrig
December

vessel
2008
Aim ­ Evaluate a range of
proposed gear modifications
to allow escape of undersized
Nephrops
Method ­ Standard twin trawl
selectivity with small mesh
cod end on control and gear
modification on the test net

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ICES WGFTFB REPORT 2008
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Funding General
Description
Conservation Area Vessel Survey
Driver
Type
Date
SGMD
Selectivity of whitefish mixed
Reduce discards
North
>1000hp

(SLA)
fisheries, particularly cod
of cod in gears
Sea
Whitefish
Mid
selectivity
used to target
twinrig
February

whitefish
vessel
2009
Aim ­ to evaluate the use of a
flexible sorting grid combined
with the horizontal separator
panel. The horizontal panel
has been shown to be effective
in separating cod (plus
anglers and flats) below the
panel from haddock and
whiting above. The grid is
planned to allow retention of
large fish from the lower part
of the net while allowing
smaller and younger fish to
escape.
Method ­ A flexible grid will
be installed in the lower part
of the net. Orientation of the
grid and the behaviour of the
fish at the grid will be
monitored by TV camera.

Catchability in Survey trawls
FRS has just completed a 3 year project on the catchability of commercial fish in the
GOV & angler fish survey trawls. The core work was on quantifying herding and
ground gear escapes in the angler trawl. Additional work was centred on the GOV
and involved developments of the Levy et al intercalibration design and on ground
gear escapes. The work is reported in papers below.
Jones, E.G., Jones, M., Greig, T., Campbell, M. and Reid, D. G. Quantification of entrance posi
tion and catch rate of fish in a survey trawl in relation to season and time of day using
multibeam sonar and video cameras. Presented at ICES Symposium on "Fishing gear in
the 21st Century", November 2006, Boston, USA.
Kynoch, R.J., Peach, K. & Reid, D.G. To assess the effect of a GOV (Chalut 36/47) rigged with a
modified rockhopper ground gear on gear geometry and survey trawl catches using the al
ternate haul method Presented at ICES Symposium on "Fishing gear in the 21st Century",
November 2006, Boston, USA.
Reid, D. G., Bova, D.J., Peach, K., Jones, E.G., Kynoch, R.J. & Fernandes, P.G. Angler fish
catchability for swept area abundance estimates in a new survey trawl. Presented at ICES
Symposium on "Fishing gear in the 21st Century", November 2006, Boston, USA.
Reid, D. G., Kynoch, R. J., Penny, I., & Peach, K. (2007). Estimation of catch efficiency in a new
angler fish survey trawl. Presented at ICES Annual Science Conference, Helsinki, Finland,
September 2007. ICES CM2007/Q:22.
Fernandes, P. G., Armstrong, F., Burns, F., Copland, P., Davis, C., Graham, N., Harlay, X.,
O'Cuaig, M., Penny, I., Pout, A. C., & Clarke, E. D. (2007). Progress in estimating the abso
lute abundance of anglerfish on the European northern shelf from a trawl survey. Pre
sented at ICES Annual Science Conference, Helsinki, Finland, September 2007. ICES CM
2007/K:12.

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ICES WGFTFB REPORT 2008
Benthic impact of trawl components
This is an ongoing project linked to EU project DEGREE on modelling and filed trials
to allow the evaluation of benthic impact in terms of physical impact, biological im
pact and resuspension of sediments
Capacity, Effort and Mortality
As part of the ongoing EU project FRS are working on fine scale movements and fish
ing behaviour in the Scottish pelagic fleet, and on modelling the links between capac
ity, effort and mortality. Final report is programmed for February 2009.
Other publications from the group in 2007/08 are listed below:
Bez, N., Reid, D.G., Bouleau, M., Beare, D.J., Neville, S., Vérin, Y., Godø, O.R. and Gerritsen, H.
(2007) Acoustic data collected during and between bottom trawl stations: consistency and
common trends. Can. J. Fish & Aquat. Sci. 64, 166­180.
Bullough, L., Riley, D., Napier, I. R., Fryer, R. J., Ferro, R. S. T., & Kynoch, R. J., 2007. A year
long trial of a square mesh panel in a commercial demersal trawl. Fisheries Research 83
(2007):105­112.
Ferro, R.S.T., Jones, E.G., Kynoch, R. J., Fryer, R.J. & Buckett, B.E. (2007) Separating species us
ing a horizontal panel in the Scottish North Sea whitefish trawl fishery. ICES Journal of
Marine Science; 64: 1543 1550.
Fonteyne, R., Buglioni, G., Leonori, I. and O'Neill, F.G., (2007). Review of mesh measurement
methodologies. Fisheries Research, 85, 279 ­ 284.
Fonteyne, R., Buglioni, G., Leonori, I., O'Neill, F.G. and Fryer, R.J., (2007). Laboratory and field
trials of OMEGA, a new objective mesh gauge. Fisheries Research, 85, 197 ­ 201.
Graham, N., Ferro, R.S.T., Karp, W.A. and MacMullen, P. (2007).Fishing practice, gear design,
and the ecosystem approach--three case studies demonstrating the effect of management
strategy on gear selectivity and discards. ICES Journal of Marine Science: 64: 744­750;
Herrmann, B., Frandsen, R., Holst, R, O'Neill F.G. (2007). Simulationbased investigation of the
pairedgear method in codend selection studies. Fisheries Research, 83, 175 ­ 184.
Ingolfsson, O´. A., Soldal, A. V., Huse, I., and Breen, M. 2007. Escape mortality of cod, saithe,
and haddock in a Barents Sea trawl fishery. ­ ICES Journal of Marine Science, 64: 1836­
1844.
O'Neill, F.G., (in press). Source models of flow through and around screens and gauzes. Ocean
Engineering.
O'Neill, F.G. and Herrmann, B., (On line). PRESEMO ­ a predictive model of codend selectiv
ity­ a tool for fisheries managers. ICES J. Mar. Sci.,64: 1558 1568.
Reid, D.G., Allen, V.J., Bova, D.J., Jones, E.G., Kynoch, R.J., Peach, K.J., Fernandes, P.G. & Tur
rell, W.R. 2007. Angler fish catchability for swept area abundance estimates in a new sur
vey trawl. ICES J. Mar. Sci., 64: 1503 1511.
Reid, D.G., Annala, J. Rosen, S., Pol, M., Cadrin, S.X., and Walsh, S.J. 2007. Survey sampling
tools: Challenges, Themes and Questions. ICES J. Mar. Sci.; 64: 1607 1609.
Sala, A., O'Neill, F.G., Buglioni, G., Lucchetti, A., Palumbo, V. and Fryer, R.J. 2007. Experimen
tal method for quantifying the resistance to opening of netting panels. ICES J. Mar. Sci., 64:
1573 1578.
Anderson, J.T., Holliday, D.V., Kloser, R., Reid, D.G. and Simard, Y. (in press). Acoustic Seabed
Classification: Current Practice and Future Directions. ICES J Mar Sci.
Madsen, N., Skeide, R., Breen, M. Krag, M, L., Huse, I., Soldal, A.V. (In press). Selectivity in a
trawl codend during haulback operation--An overlooked phenomenon. Fisheries Re
search xxx (2007) xxxxxx

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ICES WGFTFB REPORT 2008
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O'Neill, F.G. and Neilson, R.D., (in press). A dynamic model of the deformation of a diamond
mesh codend of a trawl net. ASME Journal of Applied Mechanics.
O'Neill, F.G., Kynoch, R.J. and Fryer, R.J., (in press). Square mesh panels in North Sea demersal
trawls: separate estimates of panel and codend selectivity. Fisheries Research.
19.13 USA
Massachusetts Division of Marine Fisheries - Conservation Engineering
Program
Michael Pol (Report compiler) (mike.pol@state.ma.us), David Chosid and Mark
Szymanski
Further Testing of Cod-Avoiding Trawl Net Designs
Two flatfish trawl nets designed to reduce catch of Atlantic cod, the Ribas and Top
less nets, were compared against a standard flatfish net onboard a commercial fishing
vessel working around the clock. The Ribas net uses large mesh panels in its top sec
tion; the Topless net has the top section from the wings back to the belly removed.
The Topless net significantly reduced catches of Atlantic cod and sublegalsized yel
lowtail flounder; the Ribas net showed no differences. Significant diurnal differences
in the Topless net's catching efficiency for Atlantic cod Gadus morhua, sublegal yel
lowtail Limanda ferruginea, American plaice, and winter flounder were found. Our
results imply that light levels affect the behaviour and reaction of these species to
trawl nets. A manuscript titled, "Diurnal Variation within the Species Selective `Top
less' Trawl Net" was submitted to the Journal of Ocean Technology.
Development of the Five Point Haddock Trawl
Continued investigation of this semipelagic codavoiding haddock Melanogrammus
aeglefinus trawl focused on determining the stability of the net. Imaging of the net
with a Towed Underwater Vehicle and underwater cameras and net mensuration in
April 2008 demonstrated stability at varying speeds and over diverse bottom types.
Viewing of the footrope is planned for the future.
Experimental Haddock Demersal Longline Fishery in Coastal Massachusetts
Norbait© 700E, clams, and herring were tested for catch of haddock and Atlantic cod
using longlines in a cod conservation zone during April and May 2007. Trials on a
commercial fishing vessel demonstrated that Norbait had lower catches of cod than
either natural bait, and the lowest ratio of cod to legalsized haddock (0.38). Interac
tions of bait type, area of set, and trip confounded the effects of bait on catch. A
manuscript was submitted for the 2007 Haddock Symposium volume of Fisheries
Research.
Determining the best mesh size for gillnetting monkfish Lophius americanus
We fished three different (tieddown) gillnet mesh sizes for monkfish (10, 12, 14inch;
(254, 305, 356 mm) in collaboration with a commercial fisherman to determine selec
tivity curves, and to measure differences in monkfish length and/or weight. Final
field trips are currently being completed; preliminary data show increasing monkfish
length with increasing mesh size.

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ICES WGFTFB REPORT 2008
Factors Affecting Trap Hauler Design and Tuning
Minor changes to lobster gear hauling equipment can affect the length of service life
of nonbuoyant (sinking) groundline used to reduce risk if cetacean entanglement in
fixed fishing gear. Using a ropewear simulator equipped with an offshore lobster
trap hauler, the effect on rope damage of sheave profile and angle, the depth at which
the rope rides, sheave and knife material, and knife shape are under investigation.
Future Work
Primary work planned for 2008­2009 includes filming and development of a rigid
grid to exclude spiny dogfish (Squalus acanthias) in a smallmesh whiting (Merluccius
bilinearis) fishery and seasonal comparison of Newfoundland and Norwegian cod pot
designs.
NOAA Fisheries Northeast Fisheries Science Center - Cooperative Marine
Education and Research Program, Virginia Institute of Marine Science
The repulsive and feeding deterrent effects of an electropositive alloy (palladium
neodymium mishmetal) on juvenile sandbar sharks (Carcharhinus plumbeus)
Richard W. Brill (rbrill@vims.edu), Peter Bushnell, Leonie Smith, Coley Speaks, and
John Wang
This study was undertaken to measure changes in the behaviours of captive juvenile
sandbar sharks (Carcharhinus plumbeus) in the presence of an electropositive alloy
(palladium neodymium mishmetal). Our ultimate objective is to determine if electro
positive alloys might be used to reduce shark bycatch in the pelagic longline fisheries.
Palladium neodymium mishmetal clearly altered the swimming patterns of individ
ual animals and temporarily deterred feeding in groups of sharks. Individual sharks
would generally not approach ingots closer than 60 cm, nor attack pieces of cut bait
suspended within approximately 30 cm. The latter effect was, however, relatively
short lived perhaps due to social facilitation of feeding. Palladium neodymium
mishmetal clearly exhibits the potential to repel sharks from longline gear, although
optimal size and shape, distance to baited hooks, etc. remain to be determined. Be
havioural assays with captive juvenile sandbar sharks clearly provide an effective
stratagem for testing and optimizing the use of electropositive alloys as a shark by
catch reduction method.
MIT Sea Grant College Program Center for Fisheries Engineering Research
(CFER)
Cliff Goudey (cgoudey@mit.edu)
Reduced Impact Scallop Dredge
CFER has developed and tested a new scallop dredge design that eliminates the nor
mal cutting bar, using hydrodynamics to encourage the lifting and capture of scal
lops. The Hydro dredge design was developed under a $25,000 seed grant from the
Northeast Consortium (a funder of cooperative research in New England). The de
sign is based on towtank testing of the effectiveness of various hydrodynamic de
vices at raising scallops off the bottom. A prototype 2.1m dredge was constructed
and observed insitu and evaluated in fishing trials on Stellwagen Bank. Followon
research has occurred in collaboration with the University of Wales, Bangor and the
Dept. of Agriculture, Fisheries and Forestry on the Isle of Man. Testing of the new
dredge occurred out of the fishing port of Douglas both in April and August of 2007
in a commercial fishery for the great scallop (P. maximus). In these tests the Hy

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ICES WGFTFB REPORT 2008
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drodredge was less efficient at catching these scallops compared with the toothed
Newhaven dredges. However, the new dredge was found to be significantly less
damaging to the catch. In addition, the Hydrodredge was found to be especially ef
fective on queenies (A. opercularis), a scallop that, like the giant sea scallop (P. magel
lanicus), the New England species for which the design was originally intended, does
not burrow in the seabed.
Work in the US has ceased until additional funding for development and further test
ing can be secured. With CFER cooperation, a 4.6 meter Hydrodredge has been built
by a fishing company in Canada and it will be tested in April 2008 in the Canadian
fishery. Hydrodredge technology is also being evaluated in The Netherlands in col
laboration with Machinefabriek TCD/Visserijcoöperatie Urk and IMARES. A four
meter Holland beam trawl has been fitted with wheels and cups to evaluate their ef
fectiveness on flatfish.
Acoustic control of trawl door altitude
A system designed to eliminate the seabed impacts of trawl doors is under develop
ment with support from the MIT Sea Grant College Program. The system will control
the height of the trawl door using altitude measurements of a doormounted sonar.
Based on a setting established before the tow, the doors will descend to a specified
height and then "terrain follow." The technology will allow the exploitation of low
swimming pelagic species and higherswimming demersal species. It will operate
independently as long as the trawlwire scope and towing speed are kept within a
prescribed range. Therefore, the system will be useful to smaller vessels without the
complexity and cost of acousticlink sensors or an autotrawl system.
Tank tests of halfscale models were conducted in April 2008 at the St. John's flume
tank. Excellent performance of the system was revealed, both on highaspect midwa
ter doors and lowaspect bottom doors. The acoustic sensor, microprocessor control
ler, and DC motor actuators have been completed, but further development is on
hold. Our next steps are to implement the prototype system on a pair of 2.25 sq. m.
slotted trawl doors and demonstrate its functionality in the New England ground
fishery.
Whale-safe fishing gear
CFER continues its efforts to introduce the WhaleSafe Buoy into fixed gear fisheries
to reduce the entanglements of marine mammals and endangered species and the
loss of gear from buoyline weak links. By including a stem beneath the buoy with
gradual taper and stiffness, the gear is readily shed from whales at low tension in the
line, discouraging an encounter from progressing into an entanglement. Release loads
are typically less than 10% of the buoy line weaklink requirements under the Atlan
tic Large Whale Take Reduction Plan. This is not only beneficial to whales, but also
reduces gear loss from weaklink failures. Work will continue on this innovative
buoy as funding allows.
Energy Efficient, Novel Fishing Systems
CFER has formalized a program to explore opportunities to improve the energy effi
ciency of commercial fishing through the development of innovative methods and
technology. These initiatives range from wasteheat refrigeration, to passive midwa
ter fish traps, to fish attraction and control using light and acoustics, to the recapture
of acoustically trained fish released from hatcheries. CFER seeks collaborators to
broaden the scope of each of these programs.

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ICES WGFTFB REPORT 2008
University of Rhode Island ­ Rhode Island Sea Grant
Laura Skrobe (lskrobe@uri.edu), Kathleen Castro, David Beutel, and Barbara Somers
Bycatch Reduction in the Directed Haddock Bottom Trawl Fishery
After successful field testing (significant reduction of cod, yellowtail flounder, winter
flounder, witch flounder, and American plaice, as well as other species such as monk
fish and skate ­ with no reduction in haddock), the "Eliminator" trawl was submitted
to the World Wildlife Fund 2007 Smart Gear Competition and won the grand prize.
Underwater videoing of the net is being conducted, funded using a portion of the
Smart Gear prize. In addition, a grant was received through the NOAA Northeast
Fisheries Science Center (NEFSC) to investigate a smaller version of the Eliminator,
designed to fit fishing vessels with horsepower between 250 and 550. Sea sampling
will begin in 2008.
Fishery Independent Scup Survey of Eight Selected Hard Bottom Areas in Southern
New England Waters
This project is entering its fifth year of funding by the MidAtlantic Research Set
Aside (RSA). It is designed to collect scup from hard bottom sites in Southern New
England, which are unsampled by current state and federal finfish trawl surveys.
Two commercial vessels are conducting the fieldwork and the University of Rhode
Island Rhode Island Sea Grant (URI RISG) is leading the data analysis and report
preparation. Staff from the RI Department of Environmental Management Division of
Fish and Wildlife (RIDEM DFW) and the Massachusetts Division of Marine Fisheries
(MADMF) are collaborating on the project. The age distributions of the catch will be
statistically compared to each of the other collection sites, to finfish trawl data col
lected by the National Marine Fisheries Service (NMFS) and the RIDEM DFW.
Development of a Behavioural Assay to Estimate Discard Mortality of Summer Floun-
der and Winter Flounder
Funding was received through RISG to conduct research to develop and validate a
Reflex Action Mortality Predictor (RAMP) and visual marker index for predicting
delayed discard mortality of summer and winter flounder. The goals of the project
include: (1) Identify specific behavioural reflex actions and visual markers of summer
and winter flounder for use as indicators in a RAMP assay/index, and (2) validate the
accuracy of the RAMP and visual marker index for predicting delayed mortality of
trawl caught flounder. Research is expected to begin in the fall of 2008.
Fisheries Gear Research Database
The program developed and maintains a searchable database of fisheries research
and outreach projects, completed and ongoing, funded over the last thirty years by
various funding agencies: http://www.uri.edu/seagrant/fisheriesgear/. This valuable
tool covers information on fisheries related projects in monitoring, bycatch, gear type,
biology, essential fish habitat, cooperative research, and data collection. Searches can
be conducted on one category or multiple categories to view project details, reports,
and related websites.
Interactions between Sea Turtles and Vertical Lines in Fixed Gear Fisheries
A workshop was held to discuss interactions between sea turtles and the vertical lines
of fixed gear fisheries with NMFS support. The main objectives of the workshop
were: (1) to gain a common understanding of sea turtle interactions with the vertical

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lines of fixed gear fisheries, including the nature of the entanglements; (2) to explore
potential options for reducing the bycatch of sea turtles in vertical lines; and (3) to
explore ways to improve disentanglement response and reporting.
Emerging Strategies for Improving Fisheries Management
A workshop on "Emerging Strategies for Improving Fisheries Management" was
held with support from the Walker Foundation. This workshop was intended to
build upon the successful 2005 fisheries workshop held in California and the impor
tant initiatives that emerged among the participants of that conference. The goal of
the workshop was to advance the cause of fisheries selfgovernance by assembling
both commercial and recreational fishermen to discuss case studies of successful
management, research, and marketing. The workshop had an Atlantic Ocean focus,
but drew upon select examples from other North American, Icelandic, and Norwe
gian case studies. Further information can be found at the Walker Foundation web
site.
Sector Allocation as a Management Tool
The focus of this regional workshop was to provide education and information on
sector allocation as a management tool, and exploring how this method might be ap
plied to New England's quotamanaged fisheries. The workshop was intended to an
swer questions on how sectors function, and to discuss the pros and cons of this
approach. Presenters included commercial fishermen, fisheries managers, govern
ment agency spokespersons, and members of the private sector and academic institu
tions. The workshop was held in January 2008 and materials (including proceedings ­
when
completed)
are
available
on
the
website:
http://seagrant.gso.uri.edu/fisheries/sector_allocation/index.html.
Menhaden Science and Policy Symposium
A workshop on "Menhaden Science and Policy" was conducted in November 2007,
cosponsored by RISG and the RIDEM DFW. The objectives of the meeting were to
provide background information on the state of science of menhaden and to gather
information for effective management of the resource. Topics discussed included
menhaden life history, history of the menhaden fishery, current coastwide stock as
sessment, current stock assessment for Narragansett Bay, and the ecological value of
menhaden. Following the presentations, a panel of menhaden resource stakeholders
discussed resource allocation. Proceedings are available on the website:
http://seagrant.gso.uri.edu/fisheries/menhaden/index.html.
Gulf of Maine Research Institute ­ Portland, Maine
Shelly M.L. Tallack (stallack@gmri.org)
Can Rare Earth Metals Deter Spiny Dogfish? A Feasibility Study on the use of Misch-
metal to Reduce Dogfish Catches in Hook Gear in the Gulf Of Maine
Spiny dogfish, Squalus acanthias, are considered to be unacceptably abundant by
many inshore fishermen (commercial and recreational) during the summer and fall in
the Gulf of Maine. Finding a practical and economic dogfish deterrent for application
in various fishing gears is of strong interest. Industryscience collaboration afforded
six research trips during September 2007. Triangular slices of a cerium/lanthanide
alloy (`Mischmetal') were incorporated into baited hook gears (longlines and rod and
reel gear) and the catches were compared for `treatment' (Mischmetal present) versus
`control' (mischmetal absent). Some reduction in dogfish catch was recorded for rod

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ICES WGFTFB REPORT 2008
and reel (~2%) and longline (~9­25%), but these results were not statistically signifi
cant. One complicating factor was the high rate of Mischmetal dissolution, which led
to the rapid disintegration of the Mischmetal slices. In situ video footage verified that
dogfish feeding behaviour is persistent on bait, regardless of Mischmetal presence.
This footage also showed that bait pursuit by one dogfish would escalate to frenzied
feeding by multiple dogfish, with or without Mischmetal. Overall, there is little evi
dence to suggest that Mischmetal has the potential to reduce dogfish catches in either
commercial or recreational gear types in the Gulf of Maine.
New England Aquarium ­ Boston, Massachusetts
John W. Mandelman, Ph.D. (jmandelman@neaq.org)
The Shifting Baseline of Threshold Feeding Responses to Electropositive Metal Deter-
rents in Two Species of Dogfish
Due to the potential repercussions for fisheries, the use of electropositive rare earth
metals to deter sharks from interacting with baited fishing gears is undergoing exten
sive investigation across multiple species. This labbased study aimed to assess the
behavioural responses to rareearth metal variants in a squaloid, the spiny dogfish
(Squalus acanthias), and a triakid, the smooth dogfish (Mustelus canis), two species
commonly captured as bycatch in western North Atlantic commercial and recrea
tional fishing operations. In speciesspecific trials, tankacclimated animals were ex
posed to squidbaited hookgear setups. Either a lanthanide/cerium alloy
("mischmetal") or rareearth magnet (neodymiumironboride), and corresponding
chemically inert stainless steel decoys were deployed just above (mock) hooks to
"protect" associated baits. In total, 89 videotaped trials were conducted, in which the
response behaviour (e.g. approaches, flinches, general avoidances, complete disre
gard, bites) of dogfish around the baits/metals was carefully monitored. A nested re
peated measures design was utilized where animals were changed out weekly to
reduce the potential for learned behaviour, and to enhance the overall sample of ex
perimental animals. Relative to decoys, spiny dogfish were significantly more averse
(e.g. > rate of avoidances and flinches; lower bite rate) to alloys, and smooth dogfish
to magnets, when trials followed sameday routine feedings. However, bait selectiv
ity in both species progressively declined in trials following 2 and 4day periods of
food deprivation, whereby the repellents no longer had any effect. Animal density
(either three or 15 animals per tank trial) had no effect on selectivity regardless of
hunger level. Results suggest that once a threshold hunger level is surpassed, neither
metal variant appears to effectively repel these two dogfish species. The significant
interspecific variation in response to the two metals when satiated indicates possible
divergences in sensory processing of the metallic repellents and associated behav
iours between the two species.
University of New Hampshire
Pingguo He (pingguo.he@unh.edu)
Species Separation in Groundfish Trawls
A project to test a rope separator haddock trawl was completed. A raised footrope
haddock trawl was designed and tested at sea. The trawl rigging with its fishing lines
1 m off seabed seemed most suitable for reducing cod catch (by 63%) while maintain
ing haddock catch (9% reduction), when compared with regular rock hopper
groundgear with fishing lines 0.15 m off the seabed. A project to reduce small monk
fish in a monkfish trawl is being planned. The design incorporates various grid de

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ICES WGFTFB REPORT 2008
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signs to separate the monkfish by sizes, and to reduce small groundfish species. An
international haddock symposium was organized and held in 25­26 October, 2007 in
Portsmouth, New Hampshire, USA. Selected papers are being reviewed for publica
tion in a special volume in Fisheries Research.
Bycatch Reduction in Groundfish Gillnets
Demersal gillnets of various vertical heights, different hanging ratios and twine sizes
were tested to compare species composition of their catch to evaluate whether a
lower vertical nets with slack hanging and finer twine can be used to harvest floun
ders and reduce catch of cod.
Bycatch Reduction in Shrimp Trawls
A project to design and test a topless shrimp trawl to reduce pelagic species bycatch
was completed with success. The topless trawl was able to reduce herring and other
pelagic species without loss of shrimp. The design has since been used by a local fish
erman for commercial use and reported good results. Another shrimp trawl project to
modify the Nordmore grid was also completed. Three designs of modified grid sys
tems were tested. A sizesorting grid installed in from of the main Nordmore grid
was able to reduce small shrimps by 30 to 40 count/kg when shrimps caught by a net
with a regular grid were about 130 to 160 count/kg. A combined rope grid and size
sorting grid was able to reduce both small shrimps and finfish bycatch. Further work
on the sizesorting grid and modified Nordmore grid is being planned to optimize
the design for maximum reduction of small shrimps and finfish.
Reducing Seabed Impact of Trawling
A preliminary project to design and test a wheeled groundgear to reduce seabed im
pact in the whiting fishery has been completed. Further work is being planned to im
prove the design including flume tank testing and sea trials.
NOAA Fisheries Alaska Fisheries Science Center Fisheries - Behavioural
Ecology Program, Newport, Oregon, USA
Laboratory investigation of rare earth metal and magnetic deterrents with spiny dog-
fish and Pacific halibut
Michael
W.
Davis
(michael.w.davis@noaa.gov),
Allan
W.
Stoner
(al.stoner@noaa.gov), Steve M. Kaimmer (stevek@iphc.washington.edu)
Spiny dogfish (Squalus acanthias) comprise a significant unwanted bycatch on demer
sal longlines set for halibut and cod in shelf waters of the east and west coasts of
North America. In this laboratory study, attacks on baits were tested in the presence
of 2 different rareearth materials (neodymiumironboride magnets and cerium
mischmetal) believed to deter elasmobranch catch. Experiments were made with
spiny dogfish and with Pacific halibut (Hippoglossus stenolepis) in pairwise tests of the
rareearth materials and inert metal controls. Dogfish attacked and consumed baits
tested with cerium mischmetal at a lower frequency than controls. Times to attack the
baits were significantly higher in the presence of mischmetal, as were numbers of
approaches before first attack. The time differential between mischmetal and control
treatments and the number of baits consumed converged with increasing food depri
vation (1 hr, 2 d, 4 d), but treatment differences were always significant. Cerium
mischmetal appeared to be irritating to dogfish and may disrupt their bait detection
and orientation abilities. Magnets also appeared to irritate dogfish but provided no
protection for baits in feeding trials. Pacific halibut showed no reaction whatsoever to

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ICES WGFTFB REPORT 2008
the rareearth magnets or cerium mischmetal. Mischmetal, therefore, may be useful in
reducing spiny dogfish bycatch in the halibut fishery. Disadvantages in using
mischmetal in commercial operations are expense, hazardous nature, and relatively
rapid hydrolysis in seawater.
Assessing probability of discard mortality in two Alaska crab species using reflex im-
pairment
Allan W. Stoner (al.stoner@noaa.gov), Craig S. Rose, J. Eric Munk, Carwyn F.
Hammond, Michael W. Davis
Delayed mortality associated with discards of both crabs and fishes has ordinarily
been observed through tag and recovery studies or prolonged holding in deck tanks,
and there is need for a more efficient assessment method. Six reflexes were identified
in Chionoecetes bairdi (Tanner crab) and C. opilio (snow crab) that combine to provide a
useful index of crab condition and close relation to subsequent mortality. Crabs col
lected with bottom trawls in the Bering Sea were evaluated for reflex impairment and
injuries, and held to track mortality. Logistic regression revealed that reflex impair
ment provided the most parsimonious predictor of delayed mortality in C. opilio (91%
correct predictions). For C. bairdi, reflex impairment along with injury score resulted
in 82.7% correct predictions of mortality, and reflex impairment alone resulted in
79.5% correct predictions. The relationships were independent of crab gender, size,
and shell condition, and predicted mortality in crabs with no obvious external dam
age. Reflex Action Mortality Predictors (RAMP) provides substantial improvement
over earlier mortality predictors and will help to increase the scope and replication of
fishing and handling experiments. The approach should be equally valuable for a
wide range of crustaceans.
International Pacific Halibut Commission - Seattle, Washington
Effect of hook size and hook spacing on the setline catch of Pacific halibut
Bruce Leaman and Steve Kaimmer (stevek@iphc.washington.edu)
The 2007 experiment continued a 2005 experiment where fishing hook spacing's from
3.5 to 18 ft (1.1 ­ 5.5 m) and hook sizes from 13/0 to 16/0 were fished to estimate the
effects of these combinations on the weights and sizes of Pacific halibut on setlines.
Results generally show increasing catch rate by weight with increasing spacing, al
though higher fish densities diminish this effect. Hook size had little effect on the
catch of larger fish but smaller hooks caught smaller fish. The data are currently un
dergoing more detailed analysis.
Determining the hooking success of Pacific halibut on circle hooks on setline gear
Steve Kaimmer (stevek@iphc.washington.edu) and Steve Wischniowski
In 2007 we used a DIDSON sonar to observe hook attacks and hooking success of
Pacific halibut at 100 fm (183 m) water off Kodiak Island in Alaska. The 2007 effort
observed attacks on 16/0 circle hooks. In ten days, we observed 133 hook attacks re
sulting in 45 captured fish. Fish lengths ranged from 53 to 141 cm. The data collected
describe a hooking success curve that is very close to that predicted by our ongoing
stock assessment model, suggesting that the gear selectivity in this area is entirely a
function of fish size and hooking success. In 2008, we intend to collect more observa
tions with large fish on the 16/0 hooks, as well as a set of observations using the
smaller 13/0 hooks which are common in the Pacific cod (Gadus macrocephalus) fisher
ies in the area.

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ICES WGFTFB REPORT 2008
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Reducing the bycatch of spiny dogfish by using mischmetal on commercial setline
gear
Steve Kaimmer (stevek@iphc.washington.edu) and Allan Stoner (al.stoner@noaa.gov)
This was a cooperative project between the IPHC and NOAA Fisheries Alaska Fisher
ies Science Center, Fisheries Behavioural Ecology Program, Newport, Oregon. Fol
lowing a successful laboratory experiment, we fished halibut setline gear near
Homer, Alaska comparing hooks with and without pieces of mischmetal, an ioni
callyactive alloy of lanthanide metals, attached to the hooks. We did achieve a statis
tically significant 20% reduction in the catch of dogfish (Squalus acanthias) on the
mischmetal gear. There was no associated increase in the catch of halibut. Rapid dis
solution in seawater and the expense of the mischmetal would limit broad applica
tion of its use as a shark deterrent.
Assessing the effect of swivels on the setline catches of Pacific halibut and bycatch
species in British Columbia
Steve Kaimmer (stevek@iphc.washington.edu)
Most vessels using snapin gear to fish for halibut in British Columbia and southeast
ern Alaska have swivels attached to their gear, either near the snap or on the hook.
During 2008, we will assess the effects of swivels on the catches of halibut and by
catch, particularly rockfish. Based on fishermen's accounts, we expect to catch more
halibut, and perhaps much more rockfish, on the swivel equipped gear. It is believed
that on gear without swivels, many fish spiral during the retrieval process, twisting
and weakening the gangion, or wrapping up so tightly that continued spiralling re
sults in the fish coming off the hook.
Oregon Department of Fish and Wildlife - Marine Resources Program
Reducing bycatch in hook-and-line groundfish fisheries: evaluation of the effect of
increased bait height above bottom on the catch of demersal rockfishes (Sebastes)
Bob Hannah (bob.w.hannah@state.or.us), Troy Buell
We expanded our study of how increasing the height of angled baits above the bot
tom using long leaders (4.6 m) inserted between the lowermost bait and the terminal
weight (longleader gear) altered the species and size composition of the recreational
catch off the Oregon coast. Specifically, we expanded the study reported on last year
to include separate substudies of the effectiveness of longleaders when angling with
only small lures or flies or with large whole bait, and conducted additional work to
examine gear interaction effects. Sidebyside fishing with longleader and control
gear showed a strong reduction in the catch of demersal rockfishes, including yel
loweye rockfish, with longleader gear, with negligible effects on catch rates of target
species (Pacific halibut or black rockfish). Replicate drifts over the same habitat, with
and without the control gear, showed that when fishing only small lures or flies for
black rockfish the bycatch reduction effect was robust to which gear was presented
first. However, when fishing with large whole baits for Pacific halibut, the bycatch
reduction seen for yelloweye rockfish disappeared when longleader gear was pre
sented first. This suggests that there is a potential to use longleader gear to reduce
the bycatch of demersal rockfish in recreational fisheries, but only in fisheries that can
be successfully prosecuted with small lures and flies only, not large whole baits.

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ICES WGFTFB REPORT 2008
Evaluation of selective flatfish trawls as used in the nearshore groundfish fishery
Bob Hannah (bob.w.hannah@state.or.us), Nancy Gove (NMFS Northwest Fishery
Science Center)
We analyzed NMFS Northwest Fishery Science Center observer program data to
evaluate the effectiveness of selective flatfish trawls (required nearshore since 2005) at
reducing canary rockfish bycatch in the nearshore groundfish trawl fishery off Ore
gon and Washington. The data showed that some vessels were using selective flatfish
trawls effectively while some were not and the fishery as a whole had exceeded the
canary rockfish bycatch rates projected from research studies and a largescale fishery
test. Analyses aimed at determining if the nets being fished had excessive rise were
inconclusive, however anecdotal comments from fishers and net shops indicated that
nets with excessive rise were being fished by some vessels. A recommendation to
change the legal definition of selective flatfish trawls to better restrict overall rise was
forwarded to the Pacific Fishery Management Council.
Test of a combination BRD/sorting grate in the ocean shrimp (Pandalus jordani) trawl
fishery
Bob Hannah (bob.w.hannah@state.or.us), Steve Jones
We tested a rigidgrate BRD in the Oregon shrimp trawl fishery that incorporated a
lower section designed to allow the escapement of undersize shrimp and an upper
section that allows shrimp to pass into the codend but excludes all large and me
diumsized fish. The grate did increase the average size of shrimp in the codend, and
excluded fish well but also caused significant shrimp loss above that expected from
just the escape of very small shrimp. Underwater video showed that the narrowly
spaced sorting grid was causing excessive water flow towards the fish escape hole.
This research showed that rigidgrate BRDs that also sizesort shrimp are possible but
that a different design is needed.
ROV survey of soft-bottom habitats affected by shrimp trawling
Bob Hannah (bob.w.hannah@state.or.us), Steve Jones, and William Miller
We conducted an extensive ROV survey of mudbottom habitats in four areas near
Nehalem Bank to study the impacts of shrimp trawls on macroinvertebrate popula
tions. The four study sites have quite disparate trawling histories and two of the sites
are within the Nehalem Bank notrawl zone established in 2006. The study has two
main goals; determine if differences in macroinvertebrate populations correspond
with differences in trawling history as shown in logbook data and to establish a base
line macroinvertebrate survey that can be used to examine longterm changes in
macroinvertebrate populations going forward as two of the areas continue to be
trawled and two remain closed. Field work was completed in 2007.
20
New Business
20.1 Date and Venue for 2009 WGFTFB Meeting
The ICES­FAO Working Group on Fishing Technology and Fish Behaviour
[WGFTFB] (Chair: Dominic Rihan, Ireland) will meet in Ancona, Italy from 1822
May 2009
20.2 Proposals for 2009/2010 ASC ­ Theme Sessions
It is proposed to hold a theme session at the ICES ASC with following objectives:

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ICES WGFTFB REPORT 2008
| 109
1. Case studies on directed elasmobranch fisheries documenting catch levels
over time or changes in fishing patterns
2. Research with technical mitigation measures used to reduce the bycatch of el
samobranch species; and
3. Studies using other management strategies including spatial or temporal clo
sures, bycatch limits to protect elsamobranch species.
Conveners: Dominic Rihan (BIM, Ireland) and Chair of WGEF (TBC)
Scientific Justification
Fisheries for elasmobranchs are common throughout the world (Bonfil 1994). The life
histories of many of these species make them highly vulnerable to human exploita
tion or unintended mortality and therefore the incidental bycatch associated with
commercial fishing operations, leading in most cases to mortality, is an issue of global
concern. Historically, some of these fisheries have shown rapid declines in abun
dance, presumably linked to long gestation periods. It is fair to say that to date most
available mitigation techniques used to reduce charismatic species bycatch have been
directed at reducing the bycatch of marine mammals. Elasmobranchs including large
sharks and species such as manta ray are at risk due to conflicts with fishing opera
tions but to date have received limited bycatch mitigation attention. Nonetheless in
the course of research into mitigation devices for release of marine mammals, reduc
tion in elsamobranch bycatch have been observed e.g. Mauritanian pelagic fisheries.
A comprehensive review of such work has not been carried out. In addition, high
local abundances of small coastal sharks and dogfish species, particularly Squalus
acanthias, can impede commercial fisheries for other fishes, as large opportunistic
catches are quite common. Little or no research has been carried out into ways of re
ducing these catches yet there is increasing pressure from managers to do so.
20.3 ICES and other Symposia
ICES Symposium on the Ecosystem Approach with Fisheries Acoustics and Com
plementary Technologies will be held at the Institute of Marine Research in Bergen,
Norway, 16­20 June 2008. CoConveners: Egil Ona (Norway), Rudy Kloser (Austra
lia), and David Demer (USA).
An ICES Symposium on the Collection and Interpretation of Fishery Dependent Data
will be held during the summer 2010, in Galway, Ireland. Convenors: N. Graham
(Ireland), K. Nedreaas (Norway), and W. Karp (USA).
20.4 Any Other Business
From an FAO perspective, one of the objectives for FAO participation in WGFTFB is
to bring the collective expertise in fishing technology in developed countries within
reach of those in developing countries. To this end, FAO welcomes the opportunity
for WGFTFB to meet outside of the traditional ICES countries and therefore would
like the ICES Secretariat and FTC to carefully consider the offer made by SEAFDEC to
host WGFTFB in Thailand in 2010. FAO FIIT fully supports this initiative as it would
ensure the continued participation of those developing countries

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ICES WGFTFB REPORT 2008
Annex 1: List of participants
NAME
ADDRESS
PHONE/FAX
EMAIL
Abdelhak
Regional Centre of
Tel: +21228822985
abdelahmin2000@yahoo.fr
Lahnin
INRH,
Fax: +21228827415
BP 5221
Agadir, Morocco
Adnan Tokac
Ege University, Fisheries
Tel: +90 532
adnan.tokac@ege.edu.tr
Faculty,
6216580
Izmir, 35100,
Fax: +90 232
Turkey
3747450
Alain Frechet
Maurice Lamontagne
Tel: +418 7750628
Alain.Frechet@DFOMPO.GC.CA
Institute, ~
Fax: +418 7750679
850 Route de la mer,
MontJoli, G5H 3Z4,
Canada
Alessandro
CNRISMAR, Largo
Tel: +39 071
a.lucchetti@ismar.cnr.it
Lucchetti
fiera della pesca,
2078828
Ancona, 60125,
Fax: +39 071 55313
Italy
Altan Lok
Ege University Fisheries
Tel: +90 232
altan.lok@ege.edu.tr
Faculty,
3434000
Bornova, Izmir, 35100,
Fax: +90 232
Turkiye
3747450
Andres Seefoo
INAPESCA
Tel: +523143323750
Yaseefoo@yahoo.com
Mexico
Andy Revill
Cefas,
Tel: +44 1502 524
andrew.revill@cefas.co.uk
Pakefield Road,
531
Lowestoft, NR33 0HT,
Fax: +44 1502 526
UK
531
Antonio
Institute of Fishery and
Tel: +50622481196
porrasantonio@hotmail.com
Porras
Aquaculture,
Fax: +50622481585
Costa Rica
Benoit Vincent
IFREMER,
Tel : +33297873804
benoit.vincent@ifremer.fr
8 rue F Toullec,
Fax: +33 2 97873839
Lorient, 56100, France
Bent
DIFRES,
Tel: +45 3396 3200
bhe@difres.dk
Herrmann
North Sea Centre, Box
Fax: +45 3396 3260
101, Hirtshals, 9850,
Denmark
Bill Karp
Alaska Fisheries Science
Tel: +1 206 526 4000
Bill.karp@NOAA.GOV
Center (NOAA), 7600
Sand Point Way NE,
Seattle, 98115, USA
Bjarti
Faroese Fisheries
Tel: +298 353900
bjartit@frs.fo
Thomsen
Laboratory, Noatun 1, P
Fax: +298 353901
O Box 3051, Tórshavn,
Faroe Islands
Bob van
IMARES,
Tel: +31 317487181
bob.vanmarlen@wur.nl
Marlen
Haringkade 1,
Fax: +31 317487326
Ijmuiden, 1976 CP,
Netherlands
Bundit
SEAFDEC,
Tel: +66 2 4256100
bundit@seafdec.org
Chokesanguan
Suksawadee Rd.,
Fax: +66 2 4256110
Phrasamutchedi, Samut
Prakan, 10290,
Thailand

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ICES WGFTFB REPORT 2008
| 111
NAME
ADDRESS
PHONE/FAX
EMAIL
Christopher
University of New
Tel: +1 603 862 0122
chris.glass@unh.edu
Glass
Hampshire,
Fax: +1 603 862
39 College Road,
7006
Durham NH, 03824,
USA
Daniel
Institute of Marine
Tel: +4652318747
Daniel.Valentinsson@fiskeriverket.se
Valentinsson
Research,
Fax: +4652313977
P.O. Box 4,
Lysekil, S453 21,
Sweden
Dave Reid
FRS Marine Lab
Tel: +44 1224
reiddg@marlab.ac.uk
375 Victoria Road,
876544
AB9 11DB, Aberdeen,
Tel Direct: +44 1224
Scotland
295363
Fax: +44 1224
295511
Dirk
ILVO
Tel: +32496388127
dirk.verhaegle@ilvo.vlaanderen.be
Verheagele
Ankerstraat 1
8400 Ostende,
Belgium
Dominic
BIM,
Tel: +353 12144104
rihan@bim.ie
Rihan
Crofton Road,
Fax: +353 12300564
Dun Laoghaire, Co.
Dublin,
Ireland
Fabio Grati
CNRISMAR,
Tel: +39 071
f.grati@ismar.cnr.it
Largo fiera della pesca,
2078846
Ancona, 60125,
Italy
Francois
European Commission,
Tel: +32 2 298 03 28
Francois.Theret@ec.europa.eu
Theret
J 79 02/79, Brussels,
Fax: +32 2 299 48 02
1049, Belgium
Frank Chopin
FAO Rome
Tel: +3906 57055257
Francis.chopin@fao.org
Frodi B.
Faroese Fisheries
Tel: +298 353900
frodis@frs.fo
Shuvadal
Laboratory,
Fax: +298 353950
Noatun 1,
P O Box 3051,
Tórshavn,
Faroe Islands
Gerard
IFREMER,
Tel: +33 2 97 873830
gerard.bavouzet@ifremer.fr
Bavouzet
8 rue Francois Toullec,
Fax: +33 2 97873838
Lorient,
France
Gianni Fabi
CNRISMAR,
Tel: +39 071
g.fabi@ismar.cnr.it
Largo fiera della pesca,
2078825
Ancona, 60125,
Fax: +39 071 55313
Italy
Håkan
Swedish Board of
Tel: +46317430333
hakan.vesterberg@fiskeriverket.se
Vesterberg
Fisheries
Fax: +46317430444
Hans Polet
ILVOFISHERY
Tel: +3259569837
hans.polet@ilvo.vlaanderen.be
Ankerstraat 1
8400 Ostende,
Belgium
Harldur
Marine Research
Tel: +354 5752000
haraldur@hafro.is
Einarsson
Institute of Iceland,
Fax: +354 5752001
Skúlagata 4, 101,
Reykjavík,
Iceland

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ICES WGFTFB REPORT 2008
NAME
ADDRESS
PHONE/FAX
EMAIL
Huseyin
Mersin University
Tel: +90 532
ozbilginh@yahoo.com
Ozbilgin
Fisheries Faculty,
7061977
Yenisehir Campus,
Fax: +90 324
33169, Mersin,
3413025
Turkey
Irene Huse
Institute of Marine
Tel: +47 55236808
irene.huse@imr.no
Research,
Fax: +47 55236830
Nordnesgt 33,
N5817, Bergen
Norway
Jacques Sacchi
IFREMER,
Tel: +33 4 99 57 32
jacques.sacchi@ifremer.fr
Jean Monnet,
08
Sete, 34200,
France
James C.
Fisheries Dept.
Tel: +234806
Jamescogbonna@yahoo.com
Ogbonna
Nigeria
5775322
Janne
FAO, Rome
Tel: +390657052377
Janne.fogelgren@fao.org
Fogelgren
Jens Floeter
VTIOSF AG
Tel: +44 (0) 40
jens.floeter@vti.bund.de
Fischerieitechnik,
38905185
Palmelie 9,
D22767 Hamburg,
Germany
Jochen
ILVOFisheries,
Tel: +32 59 56 98 38
jochen.depestele@ilvo.vlaanderen.be
Depestele
Ankerstraat 1,
Fax: +32 59 33 06 29
Oostende, B8400,
Belgium.
Johan Lovgren
Institute of Marine
Tel: +4652318779
Johan.lovgren@fiskeriverket.se
Research,
Fax: +4652313977
P.O. Box 4,
S453 21 Lysekil,
Sweden
Jonathan O.
Bureou of Fisheries and
Tel: +6329294296
jod_bfar@yahoo.com
Dickson
Aquatic Resources,
PCA Annex Bldg, 4th
Floor Eliptical Road,
Diliman,
1100 Quezon City,
Philippines
Jose Alio
Instituto Nacional de
Tel: +58 293
jalio@inia.gob.ve
Investigaciones Agricola
4317557
Edif. INIA,
Fax: +58 293
Ave. Carupano,
4325385
Caiguire,
Cumana,Venezuela
Ken Arkley
Sea Fish Industry
Tel: +44 1482
k_arkley@seafish.co.uk
Authority,
327837
Seafish House,
Fax: +44 1482
St. Andrews Quay,
223310
Kingston upon Hull,
HU3 4QE, UK
Kris Van
ILVOFISHERIES
Tel: +3259569826
kris.vancraeynest@ilvo.vlaanderen.be
Craeynest
Ankerstraat 1
8400 Ostende,
Belgium

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NAME
ADDRESS
PHONE/FAX
EMAIL
Kristian
Faroese Fisheries
Tel: +298 353900
Krizac@frs.fo
Zachariassen
Laboratory, Noatun 1,
Fax: +298 353901
P O Box 3051,
Tórshavn,
Faroe Islands
Ludvik Krag
DIFRES,~
Tel: +45 3396 3200
lak@difres.dk
North Sea Centre,
Fax: +45 3396 3260
Box 101,
Hirtshals, 9850,
Denmark
Luis Marcano
Instituto Nacional de
Tel: +58 2934510723
lmarcano@inia.gob.ve
Investigaciones
Agriculas, Cumana,
Venezuela
Mario Rueda
Marine and Coastal
Tel: +(57) 5­4211380
mrueda@invmar.org.co
Research Institute
(INVEMAR),
Santa Marta Cerro Ponta
Betin,
Colombia
Michael Pol
Mass. Division of
Tel: +11 508
mike.pol@state.ma.us
Marine Fisheries,
9902860
1213 Purchase St,
Fax:+11 508
New Bedford, MA,
9900449
02740,
USA
Mike Breen
Fisheries Research
Tel: +44 1224
breenm@marlab.ac.uk
Services,
295474
375 Victoria Road,
Fax: +44 1224
Aberdeen, AB11 9DB,
295511
Scotland
Oumarue
IRAD/SRHOL
Tel: +27377619149
njifonjo@caramail.com
Njifonjou
PMB 77 Limbe,
Cameroon
Øystein
Aquaculture Research
Tel: +298 474756
oystein@fiskaaling.fo
Patursson
Station of the Faroes,
Fax: +298 474748
Faroe Islands
Pascal
IFREMER,
Tel : +33 297873841
pascal.larnaud@ifremer.fr
Larnaud
8 rue F Toullec,
Fax: +33 297873838
Lorient, 56100,
France
Paul Winger
Marine Institute,
Tel: +1 709 7780430
Paul.Winger@mi.mun.ca
155 Ridge Rd.,
Fax: +1 709 7780661
St. Johns, A1C5R3,
Canada
Peter Munro
Alaska Fisheries Science
Tel: +1 206 526 4292
peter.munro@noaa.gov
Center (NOAA),
Fax: +1 206 526
7600 Sand Point Way
6723
NE, Seattle, 98115,
USA
Philip
Seafish,
Tel: +44 1482
p_macmullen@seafish.co.uk
MacMullen
Saint Andrews Dock,
327837
Hull, HU3 4QE,
Fax: +44 1482
England
223310
Philip Walsh
Marine Institute,
Tel: +1 709 7780430
philip.walsh@mi.mun.ca
155 Ridge Rd.,
Fax: +1 709 7780661
St. Johns, A1C5R3,
Canada

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ICES WGFTFB REPORT 2008
NAME
ADDRESS
PHONE/FAX
EMAIL
Pingguo He
University of New
Tel: +1 603 8623154
Pingguo.He@unh.edu
Hampshire,
Fax: +1 603 8620243
137 Morse Hall,
Durham, NH, 03824,
USA
Rogvi K.
FRS, Tórshavn,
Tel: +298353900
rogvi@mfrs.fo
Rouritsen
Faroe Islands
Sofie
ILVOFISHERY
Tel: +3259569883
sofie.vandemaele @ilvo.vlaanderen.be
Vandemaele
Ankerstraat 1
8400 Ostende,
Belgium
Svein
Institute of Marine
Tel : +47 55236826
svein.lokkeborg@imr.no
Løkkeborg
Research,
Fax : +47 55236830
Nordnesgaten 50, N
5817Bergen,
Norway
Sven Gunnar
Swedish Board of
Tel: +4631609231
sven.gunnar.lunneryl
Lunneryl
Fisheries
Fax: +46317430444
@fiskeriverket.se
Tom
CEFAS,
Tel: +44 1502 524
Thomas.Catchpole@cefas.co.uk
Catchpole
Pakefield Road,
531
Lowestoft, NR33 0HT,
Fax: +44 1502 526
UK
531
Waldemar
Sea Fisheries Institute in
Tel: +48 58 7356258
moderhak@mir.gdynia.pl
Moderhak
Gdynia,
Fax: +48 58 7356110
ul.Kollataja 1,
Gdynia, 81­332,
Poland

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ICES WGFTFB REPORT 2008
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Annex 2: Agenda
21 April 08:30 ­ 09:00 Registration

09:00 ­ 09:15 Opening Address

09:15 ­ 09:30 Housekeeping Issues & Meeting Arrangements (Chair)
09:30 ­ 10:30 WGFTFB Advice & Requests during 2006/2007 (Chair)
10:30 ­ 10:50 Coffee Break
10:50 ­ 11:30 ICES Draft Science Plan & New Advisory Structure (B Karp)
11:30 ­ 12:00 Report from WGQAF (P.MacMullen)
12:00 ­ 12:15 Update on Gear Classification Topic (Chair/F.Chopin)
12:15 ­ 12:30 WWF Smart Gear Competition (A. Revill)
1300 ­ 14:00 Lunch Break
14:10 ­ 14:15 ToR a) Species Separation in demersal trawls (P He & M Pol)
14:15­ 14:30 Summary of Haddock Symposium 2007 as it relates to species
separation (M. Pol)
14:30­ 14:45 Can Yellowtail Flounder be harvested without bycatch of cod
and haddock on Georges Bank? Realtime spatiotemporal
fishing strategies (C. Glass).
14:45­ 15:00 UK trials with the eliminator trawl and a new simple method for
catch comparison analysis (A. Revill)
15:15 ­ 15:30 Questions & Discussions
15:30 ­ 16:00 Coffee Break
16:00 ­ 16:10 ToR b) on Advise to Assessment WG's (D Reid)
16:10 ­ 16:20 ToR c) on Static Gear Selectivity Manual (A Revill)
16:20 ­16:30 Size selectivity of basket traps for the gastropod Nassarius
mutabilis in the Adriatic Sea (G. Fabi)
16:30 ­16:55 ToR d) on Mitigation Measures for portected species (A
Lucchetti)
16:55­ 17:10 Turtle Excluder Device Experiments In The Central Adriatic Sea
(A. Lucchetti)
17:10 ­ 17:25 ToR d) Presentation 2 (TBA)
17:25 ­ 17:40 ToR f )Shrimp Trawl Efficiency (Chair)
17:40 ­ 18:00 ToR g) WGECO OSPAR QSR report (J Despestele)

22 April 09:00 ­ 09:10 Housekeeping (Chair)
09:10 ­ 10:30 FAO Shrimp Project Update (F Chopin)
10:30 ­ 10:45 Coffee Break
10:45 ­ 10:50 Introduction to Open Session (Chair)
10:50 ­ 11:05 Nordic Pelagic Project (F. Skúvadal)
11:05 ­ 11:25 Direct observations of large mesh capelin trawls; evaluation of
mesh escapement and gear efficiency (H. Einarsson)
11:25­ 11:45 Design and test of a topless shrimp trawl to reduce pelagic fish
bycatch in the Gulf of Maine pink shrimp fishery (P. He)
11:45­ 12:00 FISHSELECT a tool for predicting basic selective properties for
nettings (B. Hermann)
12:00­ 12:20 Technical and selective properties of T90 meshes codend
extension made of different netting stiffness (W. Moderhak)
12:20­ 12:40 Fuel Saving Initiatives in the French Fishing Industry (B.
Vincent)
12:40­ 13:00 Modeling flow through and around nets using computational
fluid dynamics (Øystein Patursson)

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ICES WGFTFB REPORT 2008
12:40 ­ 13:30 Lunch Break
13:30 ­ 15:30 Topic Group meetings
15:30 ­ 15:50 Coffee Break
15:50 ­ 17:30 Topic Group Meetings

23 April 09:00 ­ 17:00 Topic Group Meetings

24 April 09:00 ­ 09.10 Housekeeping (Chair)
09:10 ­ 10:20 Topic Group Meetings
10:20­ 10:50 Coffee
10:50 ­ 13:00 Topic Group Meetings
13:00 ­ 14:00 Lunch Break
14:00 ­ 14:30 Presentation of report, conclusions & recommendations on
Species Separation
14:30 ­ 15:20 Presentation of report, conclusions & recommendations on
Fisheries Advice
15:20 ­ 15:50 Coffee Break
15:50 ­ 16:30 Presentation of report, conclusions & recommendations on
Static Gear
16:30 ­ 17:30 Presentation of report, conclusions & recommendations on
Mitigation Methods

25 April 09:00 ­ 09:15 Housekeeping (Chair)
09:15 ­ 09:35 Report on SGPOT (B. Thomson & M.Pol)
09:35 ­ 10:20 Presentation of report, conclusions & recommendations on
Shrimp Trawls
10:20 ­ 11:00 Presentation of report, conclusions & recommendations on
WGECO request
11:00 ­ 11:15 Coffee Break
11:15 ­ 12:00 Report from WGQAF (P MacMullen)
12:00 ­ 12:30 TORs for 2009 (Chair)
12:30 ­ 12:40 Suggestions for ASC theme session topics 2009 (Chair)
12:40 ­ 12:50 Date and venue for WGFTFB 2009 meeting (Chair)
12:50 ­ 13:00 AOB and concluding remarks (Chair)
13:00 ­ 14:00 Lunch& Close Meeting

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Annex 3: Recommendations
The following table summarises the main recommendations arising from the
WGFTFB and identifies suggested responsibilities for action.
RECOMMENDATION
FOR FOLLOW UP BY:
1. WGFTFB recommends the publication of an ICES Cooperative
FTC, ICES Publications
Research Report on Species Separartion based on the work
Committee
carried out by the Topic Group.
2. The topic group will continue to collate this information on an
ACOM, AMAWGC, GFCM
annual basis, based on the issues related above and subject to
Assessment Chairs to note.
further revision of the questionnaire and better quantification of
the information where possible.
3. WGFTFB should continue to receive feedback from the
ACOM, AMAWGC, GFCM
different Expert Group's and AWAWGC, to assess the usefulness
Assessment Chairs to note.
of the information supplied and also target specific areas that are
identified of particular importance to individual assessment
WG's. WGFTFB are committed to assisting in the provision of
information to the new Benchmark workshops planned for
winter 2008/2009.
4. WGFTFB will expand the provision of information to other
ACOM, AMAWGC, GFCM
relevant groups such as GFCM in the Mediterranean.
Assessment Chairs to note.
5. WGFTFB recommend that the Topic Group work to the
FTC, FAO, ICES Publication
timetable outlined to drafte the gillnet selectivity manual. This
committee to note
will be presented to WGFTFB at the 2009 meeting.
6. WGFTFB recommend that the Compendium of Mitigation
FTC, FAOGFCM, SGBYC,
Methods deployed to minimise bycatch of protected species
WGMME, WGECO to note
developed by SGBYC and expanded on by WGFTFB should
continued to be updated as information on work being
undertaken globally becomes available.
7. WGFTFB recommend that GFCM encourage Mediterranean
FTC, FAOGFCM, SGBYC,
States instigate data collection programmes to provide a better
WGMME, WGECO to note
understanding of the bycatch issues in Mediterranean fisheries,
particularly in nonEU countries.
8. WGFTFB recommend that research in the Mediterranean on
FTC, FAOGFCM, SGBYC,
mitigation technologies be carried out under commercial
WGMME, WGECO to note
conditions and include consideration of socioeconomic effects of
introducing such technologies.
9. WGFTFB recommend as a matter of priority that GFCM
FTC, FAOGFCM, SGBYC,
instigate further development and testing of Turtle Excluder
WGECO to note
Devices in trawl fisheries in the Central Adriatic, Tunisia and the
Northeast Mediterranean given the level of turtle bycatch in
these areas.
10. WGFTFB recommend that GFCM instigate research and pilot
FTC, FAOGFCM, SGBYC,
projects to ascertain whether simple modifications to longline
WGECO to note
gears such as the use of circle hooks, different bait types and
setting depths used extensively in other parts of the world e.g.
US and Hawaii to reduce turtle bycatch are appropriate in the
Mediterranean.
11. WGFTFB recommends the issue of shrimp trawl efficiency be
SGGEM, NIPAG, STACREC,
addressed to SGGEM as a case study for consideration
FTC, ACOM
12. WGFTFB recommends further analysis of the Icelandic or
SGGEM, NIPAG, STACREC,
other suitable datasets by SGGEM.
FTC, ACOM

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ICES WGFTFB REPORT 2008
RECOMMENDATION
FOR FOLLOW UP BY:
13. WGFTFB recommends that SGGEM should consider whether
SGGEM, NIPAG, STACREC,
horizontal wingend spread can be used as an effort parameter for
FTC, ACOM
this fishery.
WGFTFB recommends that WGECO use the findings of the case
FTC, WGECO, ACOM
studies presented in the context of the OSPAR QSR 2010.
WGFTFB recommends that the case studies presented by
FTC, WGECO, ACOM
WGFTFB be used to assist in the development of a framework
that can be used to assess the efficacy of gearbased technical
measures introduced to reduce the environmental impact of
fishing.
WGFTFB recommend that definitions and terms associated with
FTC, WGQAF, WGECO, ACOM
catch, bycatch and discards be collated and assessed and the
drafting of a new definition(s) of terms used to describe the
various catch components be considered.

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ICES WGFTFB REPORT 2008
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Annex 4: WGFTFB terms of reference for the next meeting
The ICESFAO Working Group on Fishing Technology and Fish Behaviour
[WGFTFB] (Chair: Dominic Rihan, Ireland) will meet in Ancona, Italy from 18 ­ 22
May 2009 to address the following ToRs:
a ) Incorporation of Fishing Technology Issues/Expertise into Manage
ment Advice. Based on the questionnaire exercise carried out in
2005/2006, 2006/2007 and 2007/2008.
Conveners: Dave Reid (FRS, Scotland); Norman Graham (Marine Institute, Ireland);
and Dominic Rihan( BIM, Ireland)
b ) A WGFTFB topic group of experts will be formed with the following
ToRs:
i ) Identify all seine net fisheries globally and describe the gears being
used in terms of net design, rope material and construction, as well as
areas being worked.
ii ) Critically assess these fisheries, identifying the positive aspects in
terms of reduced fuel consumption, high fish quality and low bottom
impact as well as the negative aspects with respect to gear selectivity
and technological creep.
iii ) Evaluate methods for determining selectivity in these gears to allow
comparison with conventional towed gears e.g. otter trawls
iv ) Make recommendation for research/monitoring work to substantiate
(or otherwise) claims for environmental friendliness, discarding, un
accounted fishing mortality.
Conveners: Ken Arkley (SFIA, UK); Rob Kynoch (FRS, Scotland); and Harldur
Einarsson (MRI, Iceland)
c ) A WGFTFB topic group of experts will be formed with the following
ToRs:
· To review and appraise the current selectivity characteristics of the
gears used in the Area VII Nephrops trawl fisheries and Beam trawl
fisheries for flatfish in ICES areas IV and VIId; and
i ) To propose potential gear modifications that could contribute to the
future technical conservation measures needed to achieve the targets
proposed by the European Commission, while also taking into ac
count fish survival from such gear modifications.
Conveners: Dominic Rihan (BIM, Ireland); Andy Revill (CEFAS, UK) and Hans
Polet (ILVO, Belgium)
d ) A WGFTFB topic group will be formed with the following ToRs:
· Review progress with better developing scientific collaboration of
WGFTFB with GFCM on fishing technology issues in the Mediterra
nean; and specifically
· Review new research with 40mm squaremesh codends introduced re
cently into EU legislation for the Mediterranean;
· Assess the efficacy of this measure in terms of improved selectivity
and fish survival;
· Identify whether from a technical perspective that the regulation needs
to be amended i.e. twine material, meshes in the circumference.

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ICES WGFTFB REPORT 2008
Conveners: Jacques Sacchi (IFREMER, France); Antonello Sala (CNRISMAR, Italy)
and Huseyin Ozbilgin (Mersin University, Turkey)
WGFTFB will report by 16 June 2009 to the attention of the Fisheries Technology
Committee.
Supporting Information


Priority:
The current activities of this Group will lead ICES into issues related to the
effectiveness of technical measures to change size selectivity and fishing
mortality rates. Consequently these activities are considered to have a very high
priority

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ICES WGFTFB REPORT 2008
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Scientific
Action Item 3.16, 3.17, 3.18, 5.8, 5.11, 5.16, 6.3 (a)
justification and
Action Item 3.2, 3.13, 4.11.3, 4.13, 5.11 (b)
relation to action
Action Item 3.16, 3.18, 4.13, 5.8, 5.12 (c)
plan:
Action Item 3.2, 3.5, 3.16,3.17,4.13, 5.8 (d)
Term of Reference a)
Fisheries management bodies are often dependant on catch per unit effort for
stock assessment purposes and fishery/fleet based advice. Identification and use
of gear parameters that effect fishing efficiency will most likely improve the use
of commercial catches for stock assessment purposes. The topic group has the
expertise to identify such parameters and will work intersessionally, reviewing
existing initiatives e.g. EC data collection regulation and provide a list for con
sideration during the 2008 WGFTFB meeting. The information collated by the
WGFTFB has been well received by ICES assessment and other Expert Groups.
It is intended to continue with the collation of this information but further de
velopments are needed. The topic group recommends a number of changes to
improve the utility and simplicity of this work. The next questionnaire will be
based on the emergent issues identified in this report, and focused on 2008/2009.
Feedback on the content and value of this years report will be sought from the
Assessment working groups and through AMAWGC and will be used to im
prove the survey in 2009. If possible, the EC should be asked to provide up to
date information on recent TCM regulations. These will be included in the sur
vey with a request to detail likely outcomes from these measures.
Term of Reference b)
Seining, either flydragging or anchor seining are considered to be
"environmentally friendly" fishing methods with a number of positive benefits.
Traditionally the gear used tends to be of much lighter construction and as there
are no trawl doors or warps has less impact on the seabed than trawling. The
use of such light gear also means the method is very fuel efficient. Another
positive aspect of the method is that fish are only caught in the very last part of
the capture process, and therefore are not in the codend of the net very long
leading to high catch quality of fish compared to trawled fish.
In the early 1990s, in countries such as Scotland and Ireland the number of ves
sels seining declined as vessels switched to twinrig trawling, targeting species
such as monkfish and nephrops, taking advantage of relatively low fuel prices. In
recent years, however, as fuel prices have steadily increased attention once
again has shifted to this method and there has been a switch back to this method
in some countries e.g. Scotland and Ireland and interest in developing the tech
nique in other EU countries, notably France and Netherlands and further a field
in countries such as the Philippines and South Africa.
While there is no doubting the positive benefits of seining as indicated, concerns
have been expressed that there are negative aspects associated with the method
that should be addressed, given the increased interest and adoption by
fishermen globally. For instance in Scotland and Ireland there is evidence of
high discarding and highgrading as seine netters aim to maximise returns. Also
as the pressure on grounds increase and seiners are forced into areas of harder
ground, there is evidence of technological creep in seine net design with much
heavier seine ropes and heavy hopper footropes now commonly used. There are
similarly concerns in some quarters in the adoption of seine net techniques by
French and Dutch vessels given these vessels are often targeting nonquota
species such as red mullet for which there is little or no scientific assessment.

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ICES WGFTFB REPORT 2008
Scientific
Term of Reference c)
justification and
In 2008 the European Commission will focus on mitigation of discards
relation to action
associated with a number of key fisheries in community waters. Part of this
plan:
process is to identify candidate technical measures suitable for these fisheries
which will achieve measurable targeted reductions. The target discard levels are
to be fishery specific and will be reduced over a specified period so as to achieve
a Maximum Allowed Bycatch Limit (MABL). In the recent nonpaper "On the
implementation of the policy to reduce unwanted bycatch and eliminate
discards in European fisheries" the commission has identified two key fisheries,
these are:
Bottom trawl fisheries in ICES area VII targeting Nephrops and;
Beam trawling for flatfish in ICES areas IV and VIId
Proposed MABL targets for fishery (i) are to be based on a baseline estimate of
50% (by weight) and 60% (by number) and are reduced over a period of five
years to be no more than 10% (by weight) and 15% (by number) of the total
catch (MABL). During year 1 and 2, the rates are to be reduced by 50% year on
year, while overall reductions of 60, 70 and 80% compared to the baseline level
will be expected in years 3, 4 and 5.
For fishery (ii) the baseline level is assumed to be70 and 80% by weight and
number respectively. The final target after 6 years is set at no more than 15 and
20% with reductions during the 3rd, 4th, 5th and 6th years of at least, 50%, 60%,
70% and 80% of the original baseline levels.
Clearly these represent significant reductions and stiff targets in overall discard
fisheries. However, in order to achieve these, modifications to the current range
of technical conservations measures are required.
Term of Reference d)
At the 2007 WGFTFB meeting a recommendation was made for better
collaboration between WGFTFB and GFCM on gear technology issues. It would
be opportune to determine if progress has been made on this objective in 2009.
In this context it woul also seem an opportune time to consider the new 40mm
square mesh codend regulations introduced into the Mediterranean.
Mediterranean demersal trawl fisheries traditionally operate using small
diamondshape meshes in the codend, which tend to retain almost all animals.
Furthermore, the use of such small mesh sizes leads to a bycatch which is of low
commercial value and often almost entirely discarded. In order to reduce
mortality rates for juveniles and discards of dying marine organisms by fishing
vessels, Council Regulation (EC) No. 1967/2006, concerning management
measures for the sustainable exploitation of fishery resources in the
Mediterranean, establishes that it is appropriate to provide for increases in mesh
sizes for trawl nets used for fishing for certain species of marine organisms and
for the mandatory use of squaremeshed netting.
Furthermore, the (EC) 1967/2006 establishes in Annex II point 7 that technical
specifications limiting the maximum dimensions of some parts of the trawl nets
along with the maximum number of nets in multirig trawl nets. Establishing
the maximum dimension and number of fishing gears per vessels represent a
way to control and limit the fishing effort. The effect and efficiacy of these
measures should be assessed.
Resource
The research programmes, which provide the main input to this group, are
requirements:
already underway, and resources are already committed. The additional
resource required to undertake additional activities in the framework of this
group is negligible.
Participants:
The Group is normally attended by some 50­70 scientists and invited experts.
Secretariat
None.
facilities:
Financial:
None required. Having overlaps with other meetings of expert groups of FTC
increases efficiency and reduces travel costs.

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Linkages to
The questions of bycatch reduction, fisheries information and survey
advisory
standardization are of direct interest to ACOM.
committees:
Linkages to other
This work is of direct relevance to the Working Group on Ecosystem Effects of
committees or
Fisheries, WG on Fishery Systems, WG on International Bottom Trawl Surveys,
groups:
Baltic Committee, Marine Habitat Committee, Resource Management Commit
tee and Living Resources Committee and the Assessment Working Groups.
Linkages to other
The work of this group is closely aligned with similar work in FAO and also the
organizations:
EU Regional Advisory Councils.

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ICES WGFTFB REPORT 2008
Annex 5: Study Groups
It is recommended that a Study Group on Turned 90° Codend Selectivity, focusing
on Baltic Cod Selectivity [SGTCOD] Chairs: Bent Hermann, DIFRES, Denmark and
Waldemar Moderhak MIR, Poland) be established and meet in to address the fol
lowing ToRs:
a ) To evaluate the effect of turning diamond netting by 90° (T90) on
codend selectivity.
b ) To improve knowledge on the size selection processes in T90 codends
compared to T0 codends (normal direction of diamond netting).
c ) To attempt to quantify the magnitudes of the effects of different factors
(construction, generic netting properties, stock specific morphology,
catch composition)
d ) To develop a guide on T90 codend constructions with respect to size
selection properties and optimal construction; and
e ) To review available data on fish survival and in particular cod escap
ing from T90 codends.
SGTCOD will report by xxxx for the attention of the Fisheries Technology Commit
tee.
Supporting Information


Priority:
The current activities of this Group will lead ICES into issues related to the ef
fectiveness of technical measures to change size selectivity and fishing mortality
rates. Consequently these activities are considered to have a very high priority
Scientific
Action Item 3.16, 3.17, 3.18, 5.8, 5.11, 5.16, 6.3
justification and

relation to action
The use of T90 codends is legal in the Baltic Sea cod fishery and there is an in
plan:
creasing global interest in using T90 for towed fishing gears. The basic mecha
nisms governing T90 performance are, however, not well understood or
quantified.

In order to address this it is proposed to set up a Study Group specifically to
look at all issues relating to the use of T90 netting as a means of improving se
lectivity. The objectives will be reached by combining field experiments (size
selectivity experiments), laboratory experiments with nettings (loading by dif
ferent forces comparing mesh openness), laboratory experiments with fish mor
phology specific on Baltic cod (FISHSELECT) and theoretical approach
(structural mechanic for bending of mesh bars under load and computer simula
tions). A case study on Baltic cod will be conducted.

We expect that the benefit of T90 on size selectivity will depend on the netting
panel construction (twine thickness, twine stiffness, single/double twine, ratio
between mesh sizes (mesh bar)/twine thickness). Therefore all T90 experiments
should be evaluated against a baseline of experiments with similar diamond
mesh codends (T0) made of the same netting and having the same number of
meshes around. For the comparison of results from sea trials regarding the per
formance of T90 it is important that the trawl designs in front of the codends (T0
and T90) are identical. It is also important that the experimental design take into
account potential confounding effects like vessel size. The level of unaccounted
mortality of cod escaping through T90 codends will also be considered specifi
cally for the Baltic.

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ICES WGFTFB REPORT 2008
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Resource
The research programmes, which provide the main input to this group, are al
requirements:
ready underway, and resources are already committed. The additional resource
required to undertake additional activities in the framework of this group is
negligible.
Participants:
The Study Group is likely to attract 10­15 participants from Baltic countries and
a further 5 experts in the field.
Secretariat
None.
facilities:
Financial:
No financial implications.
Linkages to
ACOM
advisory
committees:
Linkages to other
There is a very close working relationship with all the groups of the Fisheries
committees or
Technology Committee. It is also very relevant to the Working Group on
groups:
Ecosystem Effects of Fisheries and Baltic Fisheries Committee
Linkages to other
The work of this group is closely aligned with the EU and Baltic Sea Regional
organizations:
Advisory Council.

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Annex 6: Proposed Term of Reference JFTAB
It is proposed a Joint Workshop of the ICESFAO Working Group on Fishing
Technology and Fish Behaviour [WGFTFB] and the Working Group on Fisheries
Acoustics Science and Technology [WGFAST] will be held in Ancona, Italy on 20
May 2009 CoChairs: Paul Winger (Marine Institute, Canada), Emma Jones (NIWA,
New Zealand) and Julia Parish (University of Washington, USA) to address the fol
lowing ToRs:
a ) To explore the decisions (i.e. bahvioural tradeoff's) made by fish and
crustaceans during natural behaviour, vessel avoidance, and in re
sponse to fishing gear and other platforms.
Supporting Information


Priority:
The current activities of this Group will lead ICES into issues related to the ef
fectiveness of technical measures to change size selectivity and fishing mortality
rates. Consequently these activities are considered to have a very high priority
Scientific
Action Item 3.16, 3.17, 3.18, 5.8, 5.11, 5.16, 6.3
justification and

relation to action
The second ICES Symposium on fish behaviour, entitled "Fish Behaviour in
plan:
Exploited Ecosystems" was recently held in Bergen, June 2003. Scientific research
was presented across 5 key theme sessions, culminating in 27 peerreviewed
papers (Fernö et al. 2004) with Discussion Sessions recorded by Bjordal and
Gerlotto (2004), Huse (2004), Glass and Gunn (2004), Walsh et al. (2004), and
Thiele and Fernö (2004).
One of the dominant conclusions from several of the theme sessions was the
need to challenge our traditional approaches to the study of fish behaviour. No
one would argue that the field hasn't grown rapidly, nor that our observational
techniques haven't improved remarkably. They have. But what is clear, is that
there continues to be too much observation and description of animal behaviour
without an attempt to understand why fish do what they do (Bjordal and Gerlotto
2004; Glass and Gunn 2004; Walsh et al., 2004).
This joint session presents a forum for discussion on new approaches and
interpretation of animal behaviour. We invite presentations and posters that
emphasize the functional explanations behind behavioural expression, whether
it be natural behaviour, vesselinduced behaviour, or animal behaviour in
relation to fishing gear. We want to explore the costs and benefits associated
with the decisions that animals make and how we can predict the probable (or
optimal) decision under different conditions? For example, what are the
behavioural tradeoffs that fish make in response to an attractive odour plume
when simultaneously engaged in spawning, or by contrast, what is the optimal
avoidance distance to an approaching trawler when actively engaged in
feeding?
Resource
The research programmes, which provide the main input to this group, are al
requirements:
ready underway, and resources are already committed. The additional resource
required to undertake additional activities in the framework of this group is
negligible.
Participants:
The Joint Session is likely to attract 50­100 participants from WGFTFB,
WGFAST and invited experts.
Secretariat
None.
facilities:
Financial:
No financial implications.
Linkages to
ACOM
advisory
committees:

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ICES WGFTFB REPORT 2008
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Linkages to other
There is a very close working relationship with all the groups of the Fisheries
committees or
Technology Committee and the joint sessionw ill continue to consolidate these
groups:
links.
Linkages to other
None
organizations:

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ICES WGFTFB REPORT 2008
Annex 7: Outline of CRR Report on Species Separation
1. Introduction
2. Review of recent literature on fish behaviour and species separation
(Pingguo He)
This section will review relevant information on fish behaviour and species separa
tion methods which may be potentially useful for application in separation of
groundfish species. Actual application and design of species separation devices and
strategies will be elaborated in Section 3.
Spatial and temporal differences in behaviour and distribution
Swimming ability
Fish reaction to gear components
Recent research on species separation in demersal trawls
3. Fish behaviour and strategies for avoiding and separating species in
demersal trawls
3.1 Fish behaviour and species separation species using spatial and temporal
separation (Dave Reid/Chris Glass)
· Principles
· Strategies
· Effectiveness
· Avoid encounter with unwanted species
· Employ spatial and temporal distribution characteristics to fish for target
species and to avoid bycatch species
· Use real time voluntary or nonvoluntary bycatch reporting network to
avoid area of bycatch concentration
· Use remote identification of species using acoustics, video or other sensors
· Conduct test tows
· Use specialized or alternate gear
· Vessel noise characteristics
3.2 Fish behaviour and species separation between the doors, bridles and the
mouth of the trawl (Emma Jones and Paul Winger)
· Principles
· Strategies
· Effectiveness
· Trawl Doors ­ Colour and sand cloud, bottom contact ­ sand cloud
· Trawl door design
· Quasi / Semipelagic fishing
· Nonherding trawls
· Altering sweep lengths and angles
· Modifying Wings of the net
· Counterherding devices

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Others to consider may include:
· Guide undesired species out of the trawl path
· Alter warpdepth ratios
· Reduce herding efficiency for unwanted species through
· Reduce towing speed
· Electrical stimulus
· Alter sand cloud with semipelagic doors
· Alter noise of doors, floats, etc.
· Alter visual stimuli of components of trawl mouth
· Modify contact of sweeps and bridles with spacers
· Avoid herding by increasing swept area using multiple rigs instead of
sweeps with single rig.
· Use of tickler chains
3.3 Fish behaviour and Species separation at the mouth of the trawl (Mike Pol
/Ludvig Krag /Bob van Marlen)
· Principles
· Strategies
· Modifications to the top of the trawl net
· Modifications to the net overhang
· Modifications to top panels (large mesh top panels)
· Cut back headline (topless) trawls
· Modify headline height
· Modifications to the headline of the trawl
· Modifications to the net mouth
· Modifications to the bottom of the net
· Modify height of fishing line
· Modify type or construction of ground gear
· Increase spaces between discs or bobbins
· Dropout panels
· Other modifications
· Alternative stimulation
3.4 Fish behaviour and species separation in the extension and codend (Haraldur
Einarsson/Ken Arkley)
· Principles of separations within the codend and how it compares with the
rest of the gear.
· Biological factors influencing species separations.
· Separations process is possibly throughout all capture process.
· Clarifications of extension (influence of separations).
· Uncounted mortality.
· Behaviour of stressed fish.
Rigid Devices & Sorting Devices
· Grids, SortX (Norway), SortV (Norway ­ Iceland)

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ICES WGFTFB REPORT 2008
· TEDs, JTEDs (FAO), Eurogrid, Flatfish grid (Faeroese Flexigrid)
· Yellow flounder grid
· Flexible arrangements
· Latitudinal ropes
· Horizontal panels
· Use of horizontal and inclined separator panels or ropes
· Inclined panels, Ireland's grid panel.
· Escape windows
· Provide exit openings/funnels
· Use square mesh windows
· Provide escape openings (e.g. Fish eye, radial escape panel)
· Use square mesh windows (e.g. BACOMA window)
· Different mesh in side panels in fourpanel net
· Longitudinal ropes
· Visual stimuli: dark tunnels
· Codend design
· Drop out panel location and colours in bottom of trawl (Milliken)
· Alternative mesh configurations (e.g. hexagonal meshes)
· Alternative mesh colours and characteristics
· Alter taper of net construction
· Alternative meshes including T90 and hexagonal meshes
· Alternative mesh configurations such as composite codends (square and
diamond, etc)
· Surface characteristics and construction of mesh materials
· Additional consideration for improvement
· Remote observation and release of catch
· Manipulation of water flow
4. Conclusions, future work and recommendations
· Conclusions
· Knowledge gaps
· Recommendations
5. References

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Annex 8: WGFTFB Information for other ICES Expert Groups ­ Question-
naire sent to WGFTFB members
Incorporation of Fishing Technology Issues/Expertise into Management Ad-
vice
Rationale:
Over the past few years, the nature of the advice ICES has been requested to provide
by the client commissions e.g. Norway, EU, and NAFO etc has changed considerably.
ICES is now asked to provide advice that is more holistic in nature, including infor
mation on the influence and effects of human activities on the marine ecosystem.
From the fishing technology perspective this includes information on how fishermen
are responding and adapting to changes in regulatory frameworks e.g. the introduc
tion of effort control; technological creep; fleet adaptations to other issues e.g. fuel
prices etc.
In response to this WGFTFB initiated a ToR in 2005 to collect data and information
that was appropriate for fisheries and ecosystem based advice, cosponsored by
Dominic Rihan (Ireland), Dave Reid (Scotland) and Norman Graham (Ireland).
In 2006, the FAOICES WGFTFB was formally requested by the Advisory Committee
on Fisheries Management (ACFM) to provide such information and to submit this to
the appropriate assessment working group.
This type of information is becoming more and more important at both international
and national levels. It demonstrates that the community of gear technologists have an
important role to play in this and that our expertise is considered to be highly valued.
Please note that this is intended for WGFTFB members from countries that receive
their stock/fisheries advice from ICES.
It would be greatly appreciated if you, in collaboration with whoever necessary, fill
out the questionnaire.
Thank you for your time and effort
Norman, Dave and Dominic
Introduction
This contains a series of questions relating to recent changes within the fleets in you
particular country that you may have observed. It also gives you the opportunity to
raise any issues that you think are important but are not currently recognised.
If at all possible, please try to quantify your statements or state how the information
has been derived e.g. common knowledge, personal observations, discussions with
industry etc.
a. Changes in Fleet Dynamics between 2006 and 2008
Have there been any major shifts between mesh categories (e.g. from 100mm+ to
70 ­ 90mm) and in which ICES area has this occurred?
What are the principal driving factors for this change? (e.g. effort allocation, and
fuel costs).

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ICES WGFTFB REPORT 2008
Is there a geographical shift in activity (e.g. between IV to VI ­ give the subdivi
sion if possible)?
Within a particular mesh/gear category, has there been any shift in target species
(e.g. from demersal gadoids to anglerfish; sardine to tuna etc)
Has there been any removal of effort through decommissioning schemes, of so
which fleets have been affected and has the decommissioning affected older or
newer vessels or a combination of both?
What proportion of the fleet has opted for decommissioning (express as a percent
age of the total fleet)?
b. Technology Creep
Include such issues as new gear handling methods/equipment; switch from single
to multiple trawling for example; changes in vessel design that could affect effort
etc; new fish finding equipment.
Have there been any significant changes in gear usage in specific fisheries, if so
what are the changes (e.g. switch from twin to single rig trawling, beam trawl to
seine net).
In which fishery has this occurred and in what ICES areas?
Have any other technical changes occurred in particular fleets that will have re
sulted in changes in catching efficiency (e.g. changes in fishing pattern, new gears
or navigational equipment) has the change in catchability been quantified?
c. Technical Conservation Measures
Other important information could include what is the level of uptake if volun
tary, has the selectivity of these been determined and if so how does it compare
with the earlier estimates, are there any other wider benefits e.g. reduced fuel
costs, ecosystem benefits etc.
Have any new TCM's been introduced into specific fisheries? If so what are the
measures and which fleets and/or areas are affected?
Have any incentives been introduced to promote the use of more selective gears?
If so which fleets/areas are targeted and what are the incentives (e.g. additional ef
fort allocations for use of Swedish grids/SMPs)
Can the changes in selectivity (size or species) be quantified relative to `standard'
gears; if so what are the changes (e.g. shift in L50, % reduction in bycatch)
What proportion of the fleet has opted to use new TCMs (0 5; 5 highest)
Please specify regulation (national or otherwise) and fishery.
d. Ecosystem Effects
Are there any fisheries where there are known impacts on nontarget species in
cluding birds and marine mammals, ghost fishing etc?
Are there any mitigation measures in place and how effective have they been?
e. Development of New Fisheries
Briefly describe any new fisheries developed?
Have these new fisheries removed effort from others, and if so can you provide
an estimate (in terms of numbers of vessels) of how many?

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Please return both files prior to the WGFTFB meeting by email to Norman Graham
(norman.graham@marine.ie) and use a country code identifier in the file name e.g.
Norway.doc. Your information will then be collated during the WGFTFB meeting
into a common format.
ANNEX 8a: FTFB Report to WGSSDS & WGHMM
This report outlines a number of technical issues relating to fishing technology that
may impact on fishing mortality and more general ecological impacts. This includes
information recent changes in commercial fleet behaviour that may influence com
mercial CPUE estimates; identification of recent technological advances (creep); eco
system effects; and the development of new fisheries in the Southern Shelf
Assessment Area including the Celtic Sea and hake, monkfish and megrim stocks.
It should be noted that the information contained in this report does not cover fully
all fleets engaged in Southern Shelf fisheries; information was obtained from Ireland,
Belgium, Spain (Basque Country) and France.
Changes in Fleet Dynamics between 2007 and 2008
· Effort associated with French purse seine vessels targeting anchovy and
bluefin tuna has transferred to targeting red mullet, squid and whiting
with Danish Seines in the Bay of Biscay. A similar trend has been observed
in Ireland, with a switch from demersal trawling for monkfish and megrim
to Danish Seining for roundfish. It is estimated that this has increased the
Irish Seine net activity from 5 to 10 vessels in the space of one year (France:
Implications: shift in target species and gear type).
· French vessels targeting Nephrops are now reverting back to the use of a
single trawl rig to reduce fuel consumption (France: Implications: Reduced
LPUE; changes in bycatch species and length composition [Breen et al,
1996]).
· Effort in the pelagic pair trawl fisheries for sea bass, tuna and anchovy has
reduced and transferred to megrim and monkfish using demersal trawl in
VIIIa and VIIIb (France and Spain: Implications: Changes in effort and gear
type).
· Economic losses associated with French quota reductions of traditional
species such as cod, whiting and plaice in VIId and IVc have been partially
compensated for by increased catches of red mullet, sea bass and squid
(France: Implications: Increased landings of nonquota and nonassessed
species).
· French trawlers targeting whiting which traditionally operate in VIId have
switched effort into IVb due to reduced catch rates in VIId and to reduce
fuel consumption by decreasing the number of individual trips but increas
ing duration. (France: Implications: Switch in effort between assessment
areas possible issues for raising metrics).
· During 2007/2008 5% of the Belgian beam trawl fleet was removed through
decommissioning.
· During 2008 Ireland introduced a further decommissioning scheme which
aims to remove 11,140GT from the fleet register. This is targeted at vessels
over 10 years and >18m. To date applications represent ~45% of the total
target, which is expected to be over subscribed. The majority of applica

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ICES WGFTFB REPORT 2008
tions emanate from East and west coast ports from vessels which tradi
tionally target Nephrops with uptake from the South East also. No applica
tions have so far been received from vessels from the South West which
traditionally target whitefish. It is expected that much of the actual effort
removed from the decommissioning scheme may be partially negated
through the introduction of ~21 modern second hand vessels (mostly ex
French) into the fleet. These have either replaced existing older, less effi
cient vessels, or have taken advantage of `semidormant' tonnage of which
a further ~3000GT remains. (Belgium and Ireland: Reductions in Fleets).
· A portion of the Basque demersal trawl fleet now targets mackerel during
the winter months in ICES areas VIIIabd (Spain: Implications: partial
switch in effort).
· Approximately 25% of the Basque VHVO demersal fleet opted for decom
missioning during 2007/2008. This has affected older vessels. In addition
10­20% of the remaining side trawlers have been replaced by modern stern
trawlers (Spain: Implications: reduction in fleet capacity partially negated
by fleet modernisation).
· As reported in 2007 effort levels by Irish vessels in the Porcupine Bank
Nephrops fishery have increased significantly with approximately 12­14
boats consistently participating in this fishery in 2006­2008. Landings are
reported to be stable with most vessels landing 8­10 tonnes of Nephrops for
7­10 day trips. 3­4 vessels are now freezing Nephrops on board and landing
to lucrative markets in Spain. Fishermen report that nephrops have tended
to be of a much smaller size range in 2007. There was also a high percent
age of females (> 75%) in some areas and this has resulted in lower returns
to vessels (average of 9/kg for males compared to 5/kg for females). (Ire
land: Implications: Shift of effort into different fisheries).
· Despite the closure of the hake gillnet fishery in Areas VIIbk in depths >
200m for part of 2006, and subsequent regulations introduced in 2007 that
restrict the length of gear and soak time in the hake fishery, Irish gillnet
fishermen reported that the 2007/2008 hake fishery was in fact quite poor
contrary to the scientific advice. Irish gillnetters tend to work in depths be
tween 200­300m. Many vessels switched back to trawling due to poor
catches and there are now only 7­8 gillnet vessels > 12m left in the fleet
and 3­4 of these have applied for decommissioning reflected the poor re
turns in recent years. (Ireland: Reduction in effort).
· 4­5 Irish whitefish vessels (all 24m+ vessels) have increased effort in the
Rockall fishery in 2006, moving from the monkfish and mixed monkfish,
megrim, hake fisheries in Areas VIIbk to VIb. (Ireland; Implications:
Quota restrictions/Changes in fleet Dynamics).
· There has been a recent shift in effort by 4­5 Irish vessels from traditional
grounds in VIIj,g to areas further south to west of the Sicily Isles and into
Area VIIh. This is to try and avoid catching cod and these vessels are tar
geting a combination of mixed demersal species, primarily hake and non
quota species such as John Dory, red mullet. (Ireland: Implications: Shift in
effort to other areas).
· The UK beam trawlers have reduced fishing activity levels due to high fuel
prices. Many are now focussing on scalloping as opposed to fish. (UK: Im
plications: reduced fishing effort).

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ICES WGFTFB REPORT 2008
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· The Irish scallop fleet based in the south east of Ireland has been rebuild
ing after a bleak number of years and since decommissioning was intro
duced in 2005. After a period of reduction or stagnation there is now 8 >
10m vessels (1 vessel < 15m) and 3­4 < 10m vessels either participating or
preparing to participate in the scallop fishery. This adds up to around
1850kw (> 10m), which is still well under the capacity limit of 4,800kw. In
dications are that many fishermen are looking at this fishery as an attrac
tive option and this illustrates that there is a need to introduce
management measures to protect scallop stocks before effort increases to
fill the capacity limit (Ireland: Implications: shift of effort into scallop sec
tor).
Technological Creep
· There is renewed interest in seining by vessels on the south coast. Several
20­24m vessels have switched from trawling (monkfish) back to seining to
reduce operating costs. However, there are reports of discarding/high
grading by seiners due to low/fluctuating prices for round haddock and
also due to quota restrictions. There are now 10 or more seiners on the
south coast compared to only 4­5 in 2006. These vessels use 90mm north of
51° N and 100mm south of 51°N. (Ireland: Implications: Move to different
fishing method).
· As reported in 2007 an Irish vessel is currently testing an automatic Neph
rops tailing machine. This vessel works almost exclusively in the Irish Sea
and this fishery is almost a targeted tail fishery given the small size of
Nephrops. The prototype machine has proven quite effective but many fish
ermen involved in the Irish Sea nephrops fishery have expressed reserva
tions at the widespread utilisation of such machines as it may lead to
increased levels of effort in areas with an abundance of small nephrops. An
introduction of a voluntary ban on landing tailed nephrops above a certain
count per kg (80­100 tails/kg) have been muted by fishermen and co
operative managers to counter this and discourage the targeting of small
nephrops. (Ireland: Increased efficiency).
Technical Conservation Measures
· Vessels targeting Nephrops in ICES areas VIIIa and VIIIb are now given the
option to used one of three methods to improve size selectivity of Nephrops
i) increased mesh size (70 to 80mm), ii) drop out panel (60mm square mesh
belly panel) or, iii) a semirigid grid (13mm). It is unclear what the uptake
is of each device, but reduction of Nephrops discards (<9cm TL) for each
device are estimated as follows: 35% for the 13mm grid, 30% for 80mm,
25% for square mesh drop out panel (France: Implications: changes in
length profile of Nephrops catches).
· In 2006, square mesh panel (100 mm inner opening) on the top of the rear
tapered section of the trawl, to decrease catches of juvenile hakes in Neph
rops fishery in the Bay of Biscay [Council regulation (EC) n° 51/2006 (22
December 2005) and 41/2007 (21December 2006); Council regulation (EC)
n° 40/2008 (16 January 2008) and 41/2007 (21December 2006)]. It is esti
mated that this has resulted in a 25% reduction in the retention of under
size hake.

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· Belgium beam trawlers operating in VIIg are reported to be using larger
mesh (150mm) belly panels in order to reduce retention of weed and other
benthos. Belgium fishermen's organisations are promoting the use of ben
thic drop out panels and full square mesh codends and uptake is likely to
steadily increase. One vessel is currently using these devices voluntarily
but other vessels are scheduled to adopt these modifications during 2008
(Belgium: Implications: reduced bycatch of nontarget species and im
proved gadoid selectivity).
· Belgium beam trawlers have tended towards the use of chain matrix gear
over traditional tickler chain nets due to the lower towing speed and asso
ciated reductions in fuel consumption (Belgium: Implications: reduction in
overall swept area).
· Encouraged by access rights, Basque vessels which target mixed demersal
species in VIIIabd close to the French coast, are voluntarily using square
mesh panels to reduce discards (Spain: Implications: discard reduction).
· Effort in the deepwater gillnet fisheries for hake has remained very high in
2007, particularly in the southwest Porcupine area. There are still repeated
claims by Irish fishermen that there is widespread use of 100mm mesh
nets, which is illegal in Area VII. The Irish Naval Service has arrested sev
eral of these vessels for breaches of regulations including the use of under
size mesh. (Ireland: Implications: Reduced selectivity through the use of
small mesh size).
Ecosystem Effects
· Predation of fish catches by Grey seals from gillnet/tangle net fisheries has
become an increasing problem on the south coast of Ireland. Many inshore
gillnet fishermen are considering shifting into other fisheries as the prob
lems has become so bad. One fisherman (12m vessel) reported 100% losses
from tangle net gear targeting monkfish, ray and turbot from one particu
lar set and average losses to seals of between 50%75% as commonplace.
There has also been an increase in gear damage. As many as 20 or more
vessels maybe affected by this phenomenon. (Ireland: Implications: Preda
tion to fish catches).
· There has been a considerable increase in the quantities of small nephrops
on the Smalls grounds in 2007 and 2008 leading to very high landings by
boats from the East coast with a high proportion of tails to whole nephrops.
There are a number of boats (up to 10 vessels) that have participated in this
fishery but do not tail due to low crew numbers and this has lead to high
discarding/upgrading. It is also reported that the seasonal Cod Closures in
the Celtic Sea have lead to a shift in effort by nephrops vessels to the west
side of the ground leading to the size of nephrops noticeably reducing as ef
fort increases. When the boxes have reopened, initial landings taken within
the box on the east of the ground have comprised a high proportion of lar
ger whole nephrops. The introduction of these boxes has completed shifted
the previous pattern in the Smalls fishery. (Ireland: Implications: Negative
impacts of technical measure e.g. closed area).
· High discarding of cod in Area VIIbk was reported in Q3 and Q4 in 2007
due to exhaustion of quota. This has been repeated in 2008, when 80%+ of
the quota in the Celtic Sea Area was caught by midMarch. Discarding has
been widespread across all Irish demersal fleets. An example of the scale is

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ICES WGFTFB REPORT 2008
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reports from the owner of one seine net vessel, who discarded over 30
boxes of marketable cod (1­1½ tonnes) from one 5­6 day trip. The prob
lems in 2008 have been put down to poor quota management which effec
tively led to unrestricted landings during FebruaryMarch. Heaviest
landings were made by the Irish gillnet fleet of around 6­8 vessels. Heavy
landings led to very low prices and cod were sold as low as 1.20­1.40/kg
during this period. (Ireland: Discarding).
· As in 2007, vessels are now discarding 0­500g and 500­1kg monkfish to
meet quota restrictions. This discarding is reportedly at quite a high level,
particularly in around 200m400m. (Ireland: Discarding).
Development of New Fisheries
· A portion of the Belgium beam trawl fleet operating in VIId and VIIe has
targeted squid and cuttlefish during the winter months (Belgium: Implica
tions: partial switch towards nonquota and nonassessed species).
· Despite poor results from experimental trials carried out in 2007 by BIM, a
potential fishery for deepwater rose shrimp is being explored by an Irish
vessel off the south west coast. This vessel has landed samples of frozen
rose shrimp from 400­800m using standard scarper trawls with 80mm
codend mesh size and is reportedly gearing up with two specially de
signed shrimp trawls with 32mm codend mesh size. (Ireland: new fishery
for nonquota species).
Annex 8b: FTFB report to WGBFAS
This report outlines a number of technical issues relating to fishing technology that
may impact on fishing mortality and more general ecological impacts. This includes
information recent changes on ecosystem effects in the Baltic Sea and Kattegat. No
other relevant information was given.
It should be noted that the information contained in this report does not cover fully
all fleets engaged in Baltic; information was obtained from Sweden only.
Changes in Fleet Dynamics 2007 to 2008
· In the first quarter of 2008, the number of vessels fishing in the Kattegat
has decreased due to an increased effort cost (2.5 days at sea per effort day
deployed). This effort has mainly been reallocated to the Skagerrak and the
Baltic Sea. Vessels without the possibility to change area have mainly tar
get Nephrops using gridequipped trawls (This gear type is not subject to
the new effort limitation). (Sweden: Implications: reallocation of effort
from Kattegat towards the Baltic and Skagerrak.)
· In the recent years there has been an increase in the numbers of Swedish
Nephrops vessels. This has contributed to subsequent increases in effort and
landings during 2006­2007 with the highest historical catch rates. The in
crease in number of vessels may be attributed to input of new capital trans
ferred from pelagic fleets after the introduction of an ITQsystem for
pelagic species. (Sweden: Implications: increased effort).
Technical Conservation Measures
· In the Swedish trawler fleet there has been a steady increase in uptake of
the Nephrops grid since introduction into legislation in 2004. Approxi

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ICES WGFTFB REPORT 2008
mately 75% of the Nephrops trawlers operating in IIIa used the grid at some
time of the year during 2006 and 2007 (40% of Nephrops trawl landings).
This can be explained by the fact that use is mandatory on coastal waters
and that there are strong incentives due to unlimited days at sea. (Sweden:
Implications: Improved selectivity in Nephrops fisheries).
· During the first Quarter of 2008 a "day at sea" in Kattegat without the grid
was counted as 2.5 days. This has further increased the incentives to use
the sorting grid to the point were 80% of all Nephrops landings in the first
quarter of 2008 were caught with sorting grids (20% previous years).
(Sweden: Implications: changed effort allocation from cod towards Neph
rops, decreased discard rates of roundfish).
Ecosystem Effects
· The Swedish Baltic cod trawl fishery has been concentrating effort close to
the coastal areas of 25W, both due to a high abundance of fish and high
fuel prices. This costal area has been considered to be an important nursing
area for predominately juvenile cod and discarding maybe high. (Implica
tions: potential increased discard rates of juvenile cod).
Annex 8c: FTFB report to WGNSDS
This report outlines a number of technical issues relating to fishing technology that
may impact on fishing mortality and more general ecological impacts. This includes
information recent changes in commercial fleet behaviour that may influence com
mercial CPUE estimates; identification of recent technological advances (creep); eco
system effects; and the development of new fisheries in the Northern Shelf
Assessment Area including the Irish Sea.
It should be noted that the information contained in this report does not cover fully
all fleets engaged in Northern Shelf fisheries; information was obtained from Ireland,
the UK, Belgium, Netherlands and France.
Changes in Fleet Dynamics 2007 to 2008
· There has been a shift for Scottish vessels from using 100mm110mm for
whitefish on the west coast ground (area VI) to 80mm Nephrops codends in
the North Sea (area IV). Fuel costs are a major driver, in this and all fisher
ies. (Scotland: Implications: Effort shift Via to Iva, and less selective gear,
bycatch/discards).
· There is a new 2008 Scottish Conservation Credits scheme, with a number
of implications:
· In early 2008, a onenet rule was introduced in Scotland as part of the new
Conservation credits scheme. This is likely to improve the accuracy of re
porting of landings to the correct mesh size range. Another element of the
package is the standardisation of the mesh size rules for twin rig vessels so
that 80mm mesh can be used in both Areas IV and VI (north of 56°N) by
twin rig vessels ­ previously the minimum mesh size for twin rig in area
VI was 100mm. As a result there may be some migration of twin riggers
from area IV to area VI, thus switching effort from IV to VI. (Scotland: Im
plications: Selectivity is not expected to change greatly for prawns because
80mm nets must be made of 4mm single twine whereas 100mm nets were
allowed to use 5mm double twine. Whitefish selection may improve be

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cause from July 2008, all nets in the 80mm range will have to have a
110mm square mesh panel installed).
· Scottish seiners have been granted a derogation from the 2 net rule until
end Jan 2009 to continue to carry 2 nets (e.g. 100­119mm as well as
120+mm). They are required to record landings from each net on a separate
logsheet and to carry observers when requested. (Scotland: Implications:
Potential for misreporting by mesh category).
· From February 2008 there has been a concerted effort not to target cod.
Real time closures and gear measures are designed to reduce cod mortal
ity. The implication is that there will be greater effort exerted on haddock,
whiting, monk, flats and Nephrops. (Scotland: Implications: Switch in effort
to other species).
· During 2008 Ireland introduced a further decommissioning scheme which
aims to remove 11,140GT from the fleet register. This is targeted at vessels
over 10 years and >18m. To date applications represent ~45% of the total
target, which is expected to be over subscribed. The majority of applica
tions emanate from East and west coast ports from vessels which tradi
tionally target Nephrops with uptake from the South East also. No
applications have so far been received from vessels from the South West
which traditionally target whitefish. It is expected that much of the actual
effort removed from the decommissioning scheme may be partially ne
gated through the introduction of ~21 modern second hand vessels (mostly
exFrench) into the fleet. These have either replaced existing older, less ef
ficient vessels, or have taken advantage of `semidormant' tonnage of
which a further ~3000GT remains. Ireland: Implications: Reductions in
Fleets but actual impact unknown).
· The increased effort by Irish vessels in the Rockall fishery reported in 2007
has continued in 2008. There are now 9­10 Irish vessels targeting this fish
ery and it is anticipated that quotas for haddock, monkfish and megrim
will be exhausted by July/August. Current regime is 30 tonne of haddock
per month, which is barely viable for the larger vessels and is reportedly
leading to highgrading given the volatility of the round haddock market.
Two of the largest Irish whitefish vessels (34m/2000hp) have shifted effort
from deepwater species (black scabbard, orange roughy, and grenadier) in
Area VIa and VIIbk to the Rockall in 2007. One of these vessels has been
subsequently sold out of the fleet but at least 4 additional (24m+/750hp)
vessels have participated in this fishery. These vessels generally targeted
monkfish in Area VIa and VIIbc. (Ireland: Implications: Shift of effort into
Rockall fishery).
· Irish vessels have reported increased activity by the Russian fleet prosecut
ing a small mesh fishmeal fishery for haddock both inside and outside the
EU 200 mile limit at Rockall. These vessels have been observed on the
grounds much earlier than in previous years. There was a peak in haddock
abundance in April but in early May haddock were reported scarce and
the Russian vessels left the grounds) (Ireland: Implications: Increased ef
fort on Rockall haddock stock).
· As reported in 2007 effort levels by Irish vessels in the Porcupine Bank
Nephrops fishery have increased significantly with approximately 12­14
boats consistently participating in this fishery in 2006­2008. Landings are
reported to be stable with most vessels landing 8­10 tonnes of Nephrops for

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7­10 day trips. 3­4 vessels are now freezing Nephrops on board and landing
to lucrative markets in Spain. Most boats still work 80mm on Porcupine
Bank and nephrops have tended to be of a smaller size range in 2007.
There was also a high percentage of females (> 75%) in some areas and this
has resulted in lower returns to vessels (average of 9/kg for males com
pared to 5/kg for females). (Implications: Increased effort).
· During 2007/2008 5% of the Belgian beam trawl fleet was removed through
decommissioning. (Belgium: Implications: Reductions in Fleets but actual
impact unknown).
Technology Creep
· Shift from fish/monkfish twin trawling to single rig and an increase in the
use of pair trawl/seine. Also a shift by large powered whitefish vessels to
Nephrops and targeting North Sea grounds with double bag trawls. This is
very much driven by fuel costs. (Scotland: Implications: Probable reduc
tion in LPUE, possible increase in discarding).
· In January 2008, multirigs (more than 2 nets) were banned under new
Scottish legislation. However, a derogation to end April 2008 was granted
to vessels currently fishing multirigs to continue. Applies to all Scottish
boats everywhere. (Scotland: Implications: again some possible reduction
in LPUE).
· With increasing fuel prices there has been a significant switch by Irish
trawlers to reduce gear size in some cases by as much as 20%. There is also
evidence of larger vessels of once again switching from twinrigging to
single rigging to reduce fuel consumption. In the 24m+ range vessels are
now working at around 50­60% of their total power in a bid to reduce fuel
costs. (Ireland: Implications: reduction in LPUE).
· As reported in 2007 an Irish vessel is currently testing an automatic Neph
rops tailing machine. This vessel works almost exclusively in the Irish Sea
and this fishery is almost a targeted tail fishery given the small size of
Nephrops. The prototype machine has proven quite effective but many fish
ermen involved in the Irish Sea nephrops fishery have expressed reserva
tions at the widespread utilisation of such machines as it may lead to
increased levels of effort in areas with an abundance of small nephrops. An
introduction of a voluntary ban on landing tailed nephrops above a certain
count per kg (80­100 tails/kg) have been muted by fishermen and co
operative managers to counter this and discourage the targeting of small
nephrops. (Implications: Increased efficiency).
Technical Conservation Measures
· Some of the Nephrops fleet have been using SMP's with mesh sizes in the
100mm to 110mm still using a codend mesh size of 80mm x single 4mm
twine. Also vessels have been installing the smp into the end of the tapered
section of the trawl. This position offers more stability for the panel and
reduces the chance that it can twist. Note: for current year: all twinrig gear
in the 80­99mm category will have to use a 110mm square mesh panel at
15­18m from the codline. This will also apply to singlerig gears from July
2008. (Scotland: Implications: Improved selectivity).
· The option of 18 extra days if a 120mm SMP at 4­9m was used with a
95mm x 5mm double codend was not taken up by the Scottish Nephrops

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fleet in 2007. The main reasons were that fishermen claim that Nephrops
would be lost due to twisting and too many marketable haddock and whit
ing lost which the extra days would not compensate for. In 2008 this option
attracts 39 extra days but is in competition with the Scottish Conservation
Credits option whereby 21 extra days are available when a 110mm SMP is
used with an 80mm codend so again uptake is zero. (Scotland: Implica
tions: No uptake of selective gear option).
· There is possibly a 30% increase in L50 of haddock, whiting, and saithe
due to use of 110mm SMP. Smaller increase in L50 of perhaps 10% for cod
(Scotland: Implications: Improved selectivity).
· A large number of 110mm SMPs have been bought in the first months of
2008 by the prawn fleet so that they qualify for the basic Conservation
Credits scheme. Probably affects most (~80%) of the fleet. (Scotland: Impli
cations: Uptake of selective gear).
· Problems with the introduction of the 5% bycatch limits for dogfish (Squa
lus acathias) on west coast and North Sea grounds. They can be encoun
tered in large congregations but it is almost impossible for vessels to
identify them using sonar etc so they are difficult to avoid. (Scotland: Im
plications: likely discarding when encountering large aggregations).
· Regulations introduced at the start of 2008 preventing the targeting of
spurdog have created problems, particularly for inshore gillnetters off the
North Galway and Mayo coasts. Some 10 vessels which had earned an av
erage of 20k per vessel in 2007 from spurdog now have no other demersal
fishery that they can diversify into and therefore have no alternative but to
target lobster and crab with pots. Most of these vessels relied on spurdog
in 2007 to compensate earnings lost from the closure of the salmon driftnet
fishery. This regulation has also affected a small number of vessels on the
south coast and has also caused problems for trawlers which at times catch
large quantities of spurdog occasionally. The regulation may lead to dis
carding of this species. (Ireland: Implications: Discarding of dogfish and
shift of effort into different fisheries).
· Effort in the deepwater gillnet fisheries for hake has remained very high in
2007, particularly in the southwest Porcupine area. There are still repeated
claims by Irish fishermen that there is widespread use of 100mm mesh
nets, which is illegal in Area VII. The Irish Naval Service has arrested sev
eral of these vessels for breaches of regulations including the use of under
size mesh. (Ireland: Implications: Reduced selectivity through the use of
small mesh size).
· High discarding of cod in Area VIIbk was reported in Q3 and Q4 in 2007
due to exhaustion of quota. This has been repeated in 2008, when 80%+ of
the quota in the Celtic Sea Area was caught by midMarch. Discarding has
been widespread across all Irish demersal fleets. An example of the scale is
reports from the owner of one seine net vessel, who discarded over 30
boxes of marketable cod (1­1½ tonnes) from one 5­6 day trip. The prob
lems in 2008 have been put down to poor quota management which effec
tively led to unrestricted landings during FebruaryMarch. Heaviest
landings were made by the Irish gillnet fleet of around 6­8 vessels. Heavy
landings led to very low prices and cod were sold as low as 1.20­1.40/kg
during this period. (Ireland: Implications: High discarding).

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· As in 2007, vessels are now discarding 0­500g and 500­1kg monkfish to
meet quota restrictions. This discarding is reportedly at quite a high level,
particularly in around 200m400m on the Achill grounds and Stanton
Banks (Ireland: Implications: High discarding).
Ecosystem Effects
· Reports of problems with discarded longlines and gill nets along the Scot
tish west coast deep water grounds. A lot of longline activity reported at
south end Rockall plateau. (Scotland: Implications: Potential for gear con
flicts).
· Despite the closure of the hake gillnet fishery in Areas VIIbk in depths >
200m for part of 2006, and subsequent regulations introduced in 2007 that
restrict the length of gear and soak time in the hake fishery, Irish gillnet
fishermen reported that the 2007/2008 hake fishery was in fact quite poor
contrary to the scientific advice. Irish gillnetters tend to work in depths be
tween 200­300m. Many vessels switched back to trawling due to poor
catches and there are now only 7­8 gillnet vessels > 12m left in the fleet
and 3­4 of these have applied for decommissioning reflected the poor re
turns in recent years. (Ireland: excessive gear lengths and soak times).
· Under Natura 2000, UKScotland has proposed a SAC on the Stanton
Banks off the northwest coast of Donegal in Area VIa. The proposed area,
which would be closed to trawling, dissects the grounds fished extensively
by Irish vessels. While the number of vessels working this area has de
creased in the last number of years to around 5 vessels (parttime) the im
pact would nonetheless be adverse. Through the NWWRAC a case has
been made to reduce the impact of this proposed closure (Ireland: Compli
ance with regulation).
Development of New Fisheries
· Despite poor results from experimental trials carried out in 2007 by BIM, a
potential fishery for deepwater rose shrimp is being explored by an Irish
vessel off the south west coast. This vessel has landed samples of frozen
rose shrimp from 400­800m using standard scarper trawls with 80mm
codend mesh size and is reportedly gearing up with two specially de
signed shrimp trawls with 32mm codend mesh size. (Ireland: Implications:
Effort in small mesh fishery with potential for high discards).
· There has been increased catches of squid reported at Rockall in Q2 of
2008. In previous years catches of squid had been much reduced on 1990
levels but one 34m/1200hp Irish vessel is now freezing squid on board.
This vessel is landing upwards of 2­3 tonne of frozen squid per trip in ad
dition to quantities of fresh squid caught on the last days of the trip. This is
becoming of increasing importance and as quotas become exhausted at
Rockall; vessels will undoubtedly begin to target this fishery more. (Ire
land: Implications: targeting nonquota species).

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Annex 8d: FTFB report to WGNSSK
This report outlines a number of technical issues relating to fishing technology that
may impact on fishing mortality and more general ecological impacts. This includes
information recent changes in commercial fleet behaviour that may influence com
mercial CPUE estimates; identification of recent technological advances (creep); eco
system effects; and the development of new fisheries in the North Sea and Skagerrak.
It should be noted that the information contained in this report does not cover fully
all fleets engaged in North Sea fisheries; information was obtained from Scotland,
EnglandUK, Northern Ireland, France, Belgium, Netherlands, Sweden and Norway.
Changes in Fleet Dynamics 2007 to 2008
· There is a gradual shift from beam trawling on flatfish to twin trawling on
other species e.g. gurnards, and Nephrops, etc. in the Dutch fleet. A number
of beam trawlers decided to shift to other techniques such as outrigging or
flyshooting in the British Channel. Caused by TAC limitations of plaice
and sole and rising fuel costs. A detailed report on trends in the NL fleet is
attached as Annex 1 to this section. (Netherlands: Implications: reduction
in effort/landings of flatfish, transfer of effort to other species).
· There has been a shift for Scottish vessels from using 100mm110mm for
whitefish on the west coast ground (area VI) to 80mm prawn codends in
the North Sea (area IV). Fuel costs are a major driver, in this and all fisher
ies. (Scotland: Implications: Effort shift Via to Iva, and less selective gear,
bycatch/discards).
· There is a new 2008 Scottish Conservation Credits scheme, with a number
of implications:
· In early 2008, a onenet rule was introduced in Scotland as part of the new
Conservation credits scheme. This is likely to improve the accuracy of re
porting of landings to the correct mesh size range. Another element of the
package is the standardisation of the mesh size rules for twin rig vessels so
that 80mm mesh can be used in both Areas IV and VI (north of 56°N) by
twin rig vessels ­ previously the minimum mesh size for twin rig in area
VI was 100mm. As a result there may be some migration of twin riggers
from area IV to area VI, thus switching effort from IV to VI. (Scotland: Im
plications: Selectivity is not expected to change greatly for prawns because
80mm nets must be made of 4mm single twine whereas 100mm nets were
allowed to use 5mm double twine. Whitefish selection may improve be
cause from July 2008, all nets in the 80mm range will have to have a
110mm square mesh panel installed).
· Scottish seiners have been granted a derogation from the 2 net rule until
end Jan 2009 to continue to carry 2 nets (e.g. 100­119mm as well as
120+mm). They are required to record landings from each net on a separate
logsheet and to carry observers when requested. (Scotland: Implications:
Potential for misreporting by mesh category)
· From February 2008 there has been a concerted effort not to target cod.
Real time closures and gear measures are designed to reduce cod mortal
ity. The implication is that there will be greater effort exerted on haddock,
whiting, monk, flats and Nephrops. (Scotland: Implications: Switch in effort
to other species).

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ICES WGFTFB REPORT 2008
· 24 boats were decommissioned in the beginning of 2008 from the Dutch
fleet. There is also a general tendency to opt for smaller multipurpose ves
sels replacing the conventional beam trawler for fishermen left in the fleet
(Netherlands: Implications: Reduced fleet size and shift of effort into other
sectors).
· 5 beam trawlers left the Belgium fleet in 2007 (approx 5%) (Belgium: Impli
cations: Reduced effort).
· In the first quarter of 2008, the number of vessels fishing in the Kattegat
has decreased due to an increased effort cost (2.5 days at sea per effort day
deployed). This effort has mainly been reallocated to the Skagerrak and the
Baltic Sea. Vessels without the possibility to change area have mainly tar
get Nephrops using gridequipped trawls (This gear type is not subject to
the new effort limitation). (Sweden: Implications: reallocation of effort
from Kattegat towards the Baltic and Skagerrak.)
· In the recent years there has been an increase in the numbers of Swedish
Nephrops vessels. This has contributed to subsequent increases in effort and
landings during 2006­2007 with the highest historical catch rates. The in
crease in number of vessels may be attributed to input of new capital trans
ferred from pelagic fleets after the introduction of an ITQsystem for
pelagic species. (Sweden: Implications: increased effort).
· The Farne deeps Nephrops fishery has been very poor in 2008. The Nephrops
disappeared very early, so the season was very short. This will shift effort
into other fisheries for whitefish (UK: Implications: increased effort in
other fisheries).
Technology Creep
· A number of Dutch beam trawlers are continuing to investigate the `out
rigging' method as an alternative to beam trawling, similar to the work in
Belgium and UK. Some boats have also moved over to seining (fly
shooting) (mainly in the English Channel). (Netherlands: Implications:
change in effort from flatfish to range of other species).
· The Dutch Beam trawler UK153 who was trialling the electrified pulse
trawl was sold, and the skipper has opted for a smaller multipurpose ves
sel. (Netherlands: Implications: Electric bam trawl method may be obsolete
as an alternative method).
· Belgian Beam trawlers are generally fishing more with Rnets and chain
matrices than with Vnets, using tickler chains. Fishing speed for beam
trawls with Rnets is generally lower. Due to high fuel prices fewer beam
trawler use of Vnets. Fewer vessels are using the outrigger trawls. Some
beam trawlers have changed to twin trawls. All driven by fuel price. A
Numbers of national project investigations of beam trawl modifications are
continuing. (Belgium: Implications: Not clear, but fleet is in flux, and inves
tigating many alternative options for fuel and discard reduction).
· Shift in the Scottish fleet from fish/monkfish twin trawl to single rig and an
increase in the use of pair trawl/seine. Also a shift by large powered white
fish vessels to Nephrops and targeting North Sea grounds with double bag
trawls. This is very much driven by fuel costs. (Scotland: Implications:
Probable reduction in LPUE, possible increase in discarding).

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· In January 2008, multirigs (more than 2 nets) were banned under new
Scottish legislation. However, a derogation to end April 2008 was granted
to vessels currently fishing multirigs to continue. Applies to all Scottish
boats in all areas. (Scotland: Implications: again some possible reduction in
LPUE).
· There has been an increasing emphasis on the use of T90 trawls in Iceland.
Bottom trawls made entirely of T90° except in the codend are now being
constructed and 14 stern trawlers targeting cod and haddock have shifted
to T90 trawls. Some other vessels are experimenting in other fisheries as
well (Nephrops and shrimp) in area Va. Changes in catchability/efficiency
are not known but this is being driven by high fuel costs as these trawls
have reportedly reduced drag. It is known nine T90° trawls have been sold
to different Europe countries (Iceland: Implications: not known but possi
bly reduced fuel consumption).
Technical Conservation Measures
· The Dutch beam trawl fleet is sensitive to the bad reputation of beam trawl
and this is stimulating research into selective nets and reduced bottom im
pact. Combined research activities were started in 2007, mostly catch com
parison experiments but there is an industry focus to solve this image
problem (Netherlands: Implications: Improved selectivity and reduced
bottom impact potentially).
· Some of the Nephrops fleet have been using SMP's with mesh sizes in the
100mm to 110mm still using a codend mesh size of 80mm x single 4mm
twine. Also vessels have been installing the smp into the end of the tapered
section of the trawl. This position offers more stability for the panel and
reduces the chance that it can twist. Note: for current year: all twinrig gear
in the 80­99mm category will have to use a 110mm square mesh panel at
15­18m from the codline. This will also apply to singlerig gears from July
2008. (Scotland: Implications: Improved selectivity)
· The option of 18 extra days if a 120mm SMP at 4­9m was used with a
95mm x 5mm double codend was not taken up by the Scottish prawn fleet
in 2007. The main reasons were that prawns would be lost due to twisting
and too many marketable haddock and whiting lost which the extra days
would not make up for. In 2008 this option attracts 39 extra days but is in
competition with the Scottish Conservation Credits option whereby 21 ex
tra days are available when a 110mm SMP is used with an 80mm codend.
(Scotland: Implications: Possibly a 30% increase in L50 of haddock, whit
ing, saithe due to use of 110mm SMP. Smaller increase in L50 of perhaps
10% for cod).
· A large number of 110mm SMPs have been bought in the first months of
2008 by the prawn fleet so that they qualify for the basic Conservation
Credits scheme. Probably affects most (~80%) of the fleet. (Scotland: Impli
cations: Uptake of selective gear).
· Problems with the introduction of the 5% bycatch limits for dogfish (Squa
lus acathias) on west coast and North Sea grounds. They can be encoun
tered in large congregations but it is almost impossible for vessels to
identify them using sonar etc so they are difficult to avoid. (Scotland: Im
plications: likely discarding when encountering large aggregations).

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ICES WGFTFB REPORT 2008
· In the Swedish trawler fleet there has been a steady increase in uptake of
the Nephrops grid since introduction into legislation in 2004. Approxi
mately 75% of the Nephrops trawlers operating in IIIa used the grid at some
time of the year during 2006 and 2007 (40% of Nephrops trawl landings).
This can be explained by the fact that use is mandatory on coastal waters
and that there are strong incentives due to unlimited days at sea. (Sweden:
Implications: Improved selectivity in Nephrops fisheries)
· During the first Quarter of 2008 a "day at sea" in Kattegat without the grid
was counted as 2.5 days. This has further increased the incentives to use
the sorting grid to the point were 80% of all Nephrops landings in the first
quarter of 2008 were caught with sorting grids (20% previous years). (
Sweden: Implications: changed effort allocation from cod towards Neph
rops, decreased discard rates of roundfish)
· One Belgian beam trawler (1200hp) is using a combination of T90codend,
benthos release panel, big meshes in the top panel and roller gear. This is a
research project but it is expected that more vessels will be using larger
mesh sizes in the top panel of the beam trawl and/or T90 or square mesh
codends (80mm) and/or the benthos release panel. Fishermen's organisa
tion is taking initiatives to motivate fishermen to use modifications that
reduce beam trawl discards. Four beam trawlers are planning to use tech
nical modifications in 2008. The driving factor for changes is generally re
duced fuel consumption. Implications: The use of bigger meshes in the top
panel is expected to increase the species selectivity, i.e. reduce the bycatch
of roundfish species, especially haddock and whiting. (Belgium: Implica
tions: improved selectivity and voluntary use of TCM).
Ecosystem Effects
· Bycatch of benthic fauna and several nontarget fish species (e.g. gobies) in
beam trawls. Voluntarily use of longitudinal release holes in the lower
panel of the trawl, which open when nets are filled with benthos, and of
Benthic Release Panels. Research is being carried out with the industry to
optimise a Benthic Release Panel for the Dutch beam trawling segment.
Similar initiatives in Belgium (Netherlands & Belgium: Implications: re
duced benthic impact).
· Reports of problems with discarded longlines and gill nets along the Scot
tish west coast deep water grounds and in the northern North Sea. A lot of
longline activity reported at south end Rockall plateau. (Scotland: Implica
tions: potential for gear conflicts/ghost fishing).
Development of New Fisheries
· There has been an increase by Dutch vessels in Nephrops fisheries using
twin trawls. Outrigger trawls are also replacing beam trawls, or flyshoot
ing (seining) mainly for nonquota species such as red mullet and cuttle
fish. (Netherlands: Implications: These are not new fisheries but represent
new trend in Dutch fishing resulting in effort and target species shift. Full
implications not yet known).
· Belgium: wide range of experimental new fisheries being tried in Belgium
­ see Annex 2
· Squid fishery in Moray Firth continues to develop when species available
on grounds, using very unselective 40mm mesh. Not much takeup in 2007

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due to few squid. (Scotland: Implications: 40 mm mesh means potential
high bycatch of young gadoids esp. cod and haddock. This fishery may
provide an alternative outlet for the Nephrops fleet seasonally, and hence
reduce effort in that sector).
Economic report on Netherlands fishing fleet 2007
This information is taken from:
Taal, C., Bartelings, H., Klok, A., van Oostenbrugge, J.A.E. 2007. Fisheries in figures 2007. The
Hague, LEI, 2007, Report PR 07.04; ISBN 978­90­8615­192­9.
General
The revenue of 438 million euros generated by the Dutch highsea and coastal fisher
ies in 2006 was slightly lower than in the previous year. The total turnover, including
the fish farming sector (48 million euros), amounted to 486 million euros.
The cutter fleets revenue increased (by 7%) to 256 million euros. The large highsea
fishing fleet recorded a landing value of 125 million euros, a decline of almost 9% as
compared to 2005. The mussel farming sectors revenue fell by 7 million euros to 49
million euros (12%).
The active highsea and coastal fishing fleet was comprised of 440 vessels, almost the
same number as in the previous year. The number of jobs provided by the fisheries
sector declined by almost 8% to about 2,100. Following the extremely low invest
ments in 2005, the sectors investments almost trebled to 30 million euros in 2006.
The turnover of the Dutch fish auctions increased slightly to 336 million euros, whilst
the volume of landings declined by 3%. In particular, the volume of sole landed in
2006 was lower (23%), whereas the volume of plaice increased slightly (+3%). The
volume of the landings of almost all other types of fish was lower. The average land
ing price at the auctions rose by 3% to 3.42 euros per kg. The landings of shrimp in
creased slightly (2%); however, the price increased by 4%.
Cutter fisheries
The cutter sector once again recorded a net loss in 2006 (for the fifth consecutive
year). The economic loss amounted to ten million euros, almost the same as in the
previous year.
The landing value increased by almost 7% to 256 million euros. Although the de
ployment of the fleet declined by 2.5%, the total costs increased by the same percent
age as the revenue (+7%). The major cost item gas oil increased by 17% in 2006. The
average price of gas oil increased to 41 Euro cents per litre (2005: 35 Euro cents per
litre). The revenues from sole increased by 2 million euros; although the price in
creased by 22%, landings fell by 16%. The revenues from plaice increased by 4 million
euros: the price was 3% higher, and landings increased by 7%. The landing value of
shrimps increased to 38 million euros, the net result of the 3% increase in volume of
landings and the 6% increase in price. The total labour income from cutter fishing
(landing value less the technical costs) increased slightly to 54 million euros.
The number of vessels in the active cutter fleet fell to 344 cutters, and the total engine
power declined by 8% to 304,000 horse power. The number of crew members also
declined further by almost 5%, especially on the large beamtrawling cutters. Gasoil
consumption remained at roughly the same level, due to the virtually unchanged de
ployment of the fleet.

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Cutters in the 261­300 HP categories (primarily Euro cutters) recorded a total landing
value roughly equal to the level in 2005. This group exhibits a very large variation in
the costs and landing values: the highest daily landing value was 43% above average,
and the lowest 33% below. On average, the cutters operated at a net loss. The earn
ings of the crew members amounted to 42,000 euros, the same level as in the previous
year.
The largest category of large beamtrawling cutters (2,000 HP) accounted for more
than 53% of the total engine power. The deployment of these cutters increased in
2006. Although the average landing value increased by 21%, this was insufficient to
offset the greatly increased costs (fuel). Consequently, the operations, as in 2005, re
corded a loss (89,000 euros).
Shrimp cutters with an engine power of up to 261 HP recorded a 9% increase in reve
nue in 2006, and the net profit amounted to 7,000 euros per vessel.
The financial position of the cutter sector deteriorated slightly as compared to the
previous year, a year in which the sectors solvency had already exhibited a substan
tial decline. The overall cutter fisheries sectors equity at the beginning of 2005 aver
aged about 0% of the total balance sheet capital. Investments were at a low level, and
the level of loans increased slightly. The longterm borrowed capital now amount to
270 million euros, more than 960,000 euros per company. The net cash flow was nega
tive in the year under review (11 million euros).
The initial forecasts for the cutter fisheries sector in 2007 indicate a result equal to or
slightly higher than that in 2006, although on balance the sector will still operate at a
loss. The total deployment of the fleet is expected to remain virtually unchanged, at
just under 54 million HP days. Estimates based on the data until the end of Septem
ber 2007 indicate that the sectors revenue will probably be slightly higher, and will
amount to a maximum of 260 million euros.
Only a small fraction of the beamtrawler fleet will be able to operate at a profit. The
prospects for this major segment of the cutter fisheries sector remain gloomy. The
shrimp fisheries sector would appear to be having a good year; shrimp prices have
returned to a high level for the first time in many years (a few dozen percent higher),
and it would seem that the problems encountered by the sector for many years have
come to an at least temporary end. The smaller shrimp cutters, in particular, will be
able to close the year with a profit. In analogy with the previous year, the twinrigs
and snurrevod (Danish nets) would once again be appearing to achieve reasonable to
good results.
The cutter fisheries sectors labour income and net results have, in general, remained
stagnant during the past years. These are estimated to amount to about 54 million
euros, roughly the same level as in 2006.
A restructuring round is scheduled for the end of 2007, and consequently the size of
the fleet will probably decline by some 24 cutters (primarily beamtrawlers) to a total
active fleet of 320 vessels. When expressed in terms of capacity (in HP), the size of the
fleet will probably decrease by at least 15% (when expressed in terms of the flatfish
fleet, about 20%).
Large-scale high-seas fishing (pelagic fleet)
The size and composition of the large highsea fishing fleet changed once again, in
analogy with 2005, following the sale of a further two vessels outside the Nether
lands. The fleet now totals 13 freezer trawlers. With the exception of a limited num

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ber of relatively minor renovations of the vessels, virtually no further investments
were made in the fleet. The total deployment in terms of days at sea was 12% lower,
primarily due to the reduced size of the fleet. Fishing declined, in particular in Afri
can waters. A new development was the deployment of one trawler in the fishing
grounds around Chile and Peru (international waters). Landings decreased as com
pared to the previous year by 19%, to a little over 378,000 tonnes of fish. Landings of
herring, blue whiting and sardinella, in particular, exhibited a substantial decline.
Only Atlantic horse mackerel landings increased.
The total costs fell by 9%, primarily due to the reduced deployment. Following the
great increase in the price of fuel (fuel oil), this cost item now accounts for 18% of the
revenue. The average price of fuel oil was 29 Euro cents per litre.
The landing value decreased by 9% to more than 125 million euros, a decline of more
than 11 million euros. The fleet closed 2006 with a net profit of almost 7 million euros.
Table showing changes in the Belgian Fleet 2006­2008.
2006/2007
2007/2008
Outrigger trawl fisheries
4 beam trawlers
2 beam trawlers (and 1 on
(mixed fisheries)
project scale, aiming for squid,
see below)
Handline fisheries for seabass
1 catamaran
2 catamarans (one new vessel,
(seasonally: MayOctober,
replacing a beam trawler)
ICESSubarea IVc)
Scallop dredging in ICES
None.
1 beam trawler is now scallop
Subarea VIId and VIIe
dredging.
(seasonally, during winter
months)
Squid fisheries (project scale)
Several beam trawlers target
Next to those beam trawlers, 2
squid and cuttlefish in winter
beam trawlers will target squid
months in ICESSubarea VII
and cuttlefish (one with an
outrigger trawl and one with a
twintrawl)
Fisheries on project scale:
None.
3 netters (generally using
i.
Gill net fisheries for
trammel nets for sole and/or
turbot (ICESSubarea
gill nets for cod) will conduct
IVc)
experimental trials for the
mentioned passive fishing
ii.
Gill net fisheries for
methods.
cuttlefish (ICES
Subarea IVc)
iii.
Gill net fisheries for
sole (ICESSubarea
VIIf)
iv.
Whelk pots (ICES
Subarea VIIe)
v.
Pots for cuttlefish
(ICESSubarea IVc)
vi.
Longlining for seabass

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Annex 8e: FTFB report to WGWIDE
This report outlines a number of technical issues relating to fishing technology that
may impact on fishing mortality and more general ecological impacts. This includes
information recent changes in commercial fleet behaviour that may influence com
mercial CPUE estimates; identification of recent technological advances (creep); eco
system effects; and the development of new fisheries in pelagic fisheries for horse
mackerel, mackerel, anchovy, sardine, herring and blue whiting.
It should be noted that the information contained in this report does not cover fully
all fleets engaged in pelagic fisheries; information was obtained from Ireland, Nether
lands, UKScotland, Spain (Basque Country), Norway, Faroe Islands and France.
Changes in Fleet Dynamics 2007 to 2008
· The size and composition of the large Dutch highseas pelagic freezer fleet
has changed, in analogy with 2005, following the sale of a further two ves
sels outside the Netherlands. The fleet now totals 13 freezer trawlers.
Landings of herring, blue whiting and sardinella, in particular, exhibited a
substantial decline. Only Atlantic horse mackerel landings have increased
(Netherlands: Reduced number of vessels).
· The Scottish fleet stands at 23 vessels and new builds are continuing to
take place. Average age of vessels is now 6­8 years (Scotland: Improved ef
ficiency).
· No changes are reported in the Norwegian Pelagic Fleet.
· Rising fuel prices has meant that a very high percentage of the total quotas
for pelagic species have been landed locally by Irish vessels this season.
Proximity of fish to port is now a driving factor in determining port of
landing compared to a few years ago when Irish vessels preferred to steam
to Norway or Scotland to land due to higher prices for mackerel. This has
been a positive development to the processing industry in Killybegs (Ire
land: Implications: shift in fishing effort).
· Most of Irish blue whiting quota in 2008 has been frozen for human con
sumption instead of reduction to fish meal. This has been a very positive
development and the fish processing factories for the first time have re
ported making profits from the blue whiting fishery. Irish landings have
been supplemented by Norwegian, Danish and Faroese vessels (Ireland:
Implications: increasing focus on blue whiting fishery).
Technological Creep
· Two Icelandic pelagic trawlers and three bottom trawlers have changed
from using steel wires to dynex warps. Changes in the type of warps in the
pelagic fishery for blue whiting and to some extent for herring in area Va,
Vb, VIa and VIb. Some reports of this in Scottish and Irish pelagic fleet
also. (Iceland: Implications: Not known, probably improved in fuel effi
ciency).
Technical Conservation Measures
· In the Blue whiting fishery, both Icelandic and Faroese vessels are using
flexible grids with 55 mm between bars to exclude cod and saithe from

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catches of blue whiting. Trials with this approach being conducted in
Norway, no uptake yet. (Iceland & Faroe Islands: Implications: There are
predominantly large cod and saithe in the areas where the Blue whiting is
caught, thus the grid is believed to reduce bycatch of those species by
>90%. 80% uptake)
· Pelagic vessels in Scotland and Ireland have been fitting escape
grids/panels. These are believed to allow release of juvenile mackerel,
horse mackerel and herring. Recent trials gave equivocal results. Uptake
around 50% in Irish fleet and 10% in Scottish fleets. (Scotland and Ireland:
Implications: possible reduced mortality on recruiting year classes, but no
data on survival rates from escaping fish is available and therefore could
be a source of unaccounted mortality).
Ecosystem effects
· As reported in 2006 and 2007, management regulations in the scad fishery,
restricting the bycatch of mackerel to 5% has lead to widespread slipping
in the pelagic fisheries when catches have been mixed. This discarding is
reported to be substantial. There is also evidence of high grading in the
mackerel fishery as due to economic pressures vessels are only landing
mackerel of 300g+ and discarding catches of smaller fish. Again the levels
of discarding are quite high compared to actual reported landings (Scot
land: Implications: discarding).
· Norwegian trials estimated mortality of mackerel after crowding and slip
ping in purse seines has been continuing. Three trials were completed in
2007, crowding for 10­15 min, gave mortality rates of 80­100%. Work will
continue with herring in 2008 and a large project is planned for 2009,
which will also include new design of the purse seine, cooperation with
the industry (Norway: Implications: unaccounted fishing mortality).
New Fisheries
· Up to eight of the pelagic vessels have continued to fish for boarfish
(Capros aper) during Q4 2007 and Q1 2008. Two vessels fished for this spe
cies in 2006 and approximately 8 vessels in 2007. With the very short fish
ing time now on all of the pelagic species this new fishery has been
identified as an opportunity to extend the vessels operating time. The fish
are suitable only for fishmeal production with a good quality oil content
(between 8­10%) but discharging from the vessels and handling in the fac
tories is proving very difficult with the discharge in particular an ex
tremely slow process. Nonetheless landings by Irish vessels have
continued to increase and are now probably in excess of 5,000­6,000 tonnes
valued at around 1 million. An initial biological study reports that fishing
effort has not had any significant impact on the stock but without man
agement measures the stock may come under pressure quite quickly given
it is a relatively slow growing pelagic species. (Ireland: Development of
new fishery for species with limited scientific data available).

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Annex 8f: FTFB Report to AFWG
This report outlines a number of technical issues relating to fishing technology that
may impact on fishing mortality and more general ecological impacts. This includes
information recent changes in commercial fleet behaviour that may influence com
mercial CPUE estimates; identification of recent technological advances (creep); eco
system effects; and the development of new fisheries in the Arctic Fisheries areas.
It should be noted that the information contained in this report does not cover fully
all fleets engaged in fisheries; information was obtained from Iceland, Faroe Islands
and Norway.
Changes in Fleet Dynamics 2007 to 2008
· In the Faroese pair trawler fleet mainly targeting saithe there has been a
substantial change in resent years. One of the major shipowner with eight
vessels (four pairs) was allowed by the Fisheries Ministry to replace these
old vessels with six new vessels. The new vessels were slightly larger but
by reducing the number from eight to six vessels the total size (length,
width, depth) and power (kW) should be maintained. The first new pair
was introduced in late 2002. After one year in operation these two vessels
were able to land twice as much fish as an old pair (FTFBWG, 2004). The
second pair started fishing in October 2007 and the third pair in December
2007. No estimate has been made of the increase in fishing capacity of the
latter two pairs compared to old vessels (Faroe Islands: Implications: In
creased efficiency).
· In the Faroese fleet of small trawlers (Hp<500) vessels are now using spe
cific trawls in specific fisheries as compared to general standard trawls
used for many different fish species. The motivation for this is high fuel
prices (Faroe Islands: Implications: more targeted fisheries).
· As a result of increasing fuel prices several large Faroese DeepSea trawl
ers have plans to move to pair trawling (Faroe Islands: Implications: shift
to different fisheries).
· There has been a reduction of 2% by tonnage in the Icelandic large stern
trawler fleet and a reduction of 45 by number and 5% by tonnage in the
rest of the dermersal fleet between 2006 and 2007. There were 107 Icelandic
boats that opted for decommissioning in 2007 or 11.8% of the fleet (Iceland:
Implications: reduced vessel numbers).
· At least five large Icelandic stern trawlers have switched from single to
twin rig trawling targeting cod and haddock (Iceland: Implications re
duced LPUE)
Technology Creep
· Faroese pairtrawlers are planning experiments with double trawls instead
of a single trawl (Faroe Islands: Implication: increased gear efficiency).
· The fishingday management system has been in place in the Faroes since
1996. Several stakeholders in the fishing industry have raised their con
cerns that the management system is undermined due to technical creep in
the Faroese fishing fleet. The Fisheries Ministry has appointed a committee
to describe developments and estimate technical creep in the different

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parts of the Faroese fishing fleet. This committee will report in June 2008
(Faroe Islands: Implications: identification of technology creep impacts).
· Three Icelandic bottom trawlers have changed from using steel wires to
dynex warps to improve fuel efficiency (Iceland: Implications: reduced fuel
consumption).
· There has been an increasing emphasis on the use of T90 trawls in Iceland.
Bottom trawls made entirely of T90° except in the codend are now being
constructed and 14 stern trawlers targeting cod and haddock have shifted
to T90 trawls. Some other vessels are experimenting in other fisheries as
well (Nephrops and shrimp). All in area Va. Changes in catchabil
ity/efficiency are not known but this is being driven by high fuel costs as
these trawls have reportedly reduced drag. It is known nine T90° trawls
have been sold to different Europe countries (Iceland: Implications: not
known but possibly reduced fuel consumption).
· Two Icelandic boats are using an underwater camera system as an aid in
the Sea cucumber fishery using dredges (Iceland: Implications: increased
efficiency).
Ecosystem effects
· In Iceland changes in length distributions on the fishing grounds with lar
ger rates of small haddock reported in some areas. Due to the amount of
small haddock, Mls regulations were reduced from 45cm to 41cm. This
meant some closed areas were opened although many remained closed
due to high catch of small cod (<55cm) (Iceland: Implications: increased ef
fort on haddock stock).
· Following reduction in cod quotas but increased quotas for haddock, the
Icelandic fleet has begun targeting haddock with all demersal fishing
gears. Most vessels avoid catching cod, which is now taken as bycatch (Ice
land: Implications: increased effort on haddock).
· Some Icelandic gillnetters have shifted over to longlines. Exact numbers
are not known. This reduction has been a result of pressures over bycatch
of seabirds and small cetaceans. The level of bycatch is not known but is
felt to be quite high given the shifts in fishing method (Iceland: Implica
tions: reduced impact on marine mammal and seabird bycatch).
· One Norwegian vessel has carried out experiments using pelagic trawl
doors fished off the seabed (approx. 5 m) with a clump (weight) connected
50 m behind the doors to ensure proper bottom contact. This method is be
ing used to target demersal trawl fishing for gadoids in the Barents Sea but
with reduced seabed contact (Norway: Implications: reduced bottom im
pact).
Development of New Fisheries
· A new fishery has developed in Iceland for sea cucumber. This new fishery
has not significantly removed effort from other fisheries. But after a col
lapse in the scallop stock (Breiðafjörður 2003 Chlamys islandica) some
smaller fish boats previously targeting scallops have now shifted to the cu
cumber fisheries (Iceland: Implications: shift of effort from scallop fisher
ies).

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Annex 8g: FTFB Report to WGECO/WGMME/WGDEEP
Ecosystem effects
· Predation of fish catches by Grey seals from gillnet/tangle net fisheries has
become an increasing problem on the south coast of Ireland. Many inshore
gillnet fishermen are considering shifting into other fisheries as the prob
lems has become so bad. One fisherman (12m vessel) reported 100% losses
from tangle net gear targeting monkfish, ray and turbot from one particu
lar set and average losses to seals of between 50%75% as commonplace.
There has also been an increase in gear damage. As many as 20 or more
vessels maybe affected by this phenomenon. (Ireland: Implications: Preda
tion to fish catches)
· There has been a considerable increase in the quantities of small nephrops
on the Smalls grounds in 2007 and 2008 leading to very high landings by
boats from the East coast with a high proportion of tails to whole nephrops.
There are a number of boats (up to 10 vessels) that have participated in this
fishery but do not tail due to low crew numbers and this has lead to high
discarding/upgrading. It is also reported that the seasonal Cod Closures in
the Celtic Sea have lead to a shift in effort by nephrops vessels to the west
side of the ground leading to the size of nephrops noticeably reducing as ef
fort increases. When the boxes have reopened, initial landings taken within
the box on the east of the ground have comprised a high proportion of lar
ger whole nephrops. The introduction of these boxes has completed shifted
the previous pattern in the Smalls fishery. (Ireland: Implications: Negative
impacts of technical measure e.g. closed area).
· High discarding of cod in Area VIIbk was reported in Q3 and Q4 in 2007
due to exhaustion of quota. This has been repeated in 2008, when 80%+ of
the quota in the Celtic Sea Area was caught by midMarch. Discarding has
been widespread across all Irish demersal fleets. An example of the scale is
reports from the owner of one seine net vessel, who discarded over 30
boxes of marketable cod (1­1½ tonnes) from one 5­6 day trip. The prob
lems in 2008 have been put down to poor quota management which effec
tively led to unrestricted landings during FebruaryMarch. Heaviest
landings were made by the Irish gillnet fleet of around 6­8 vessels. Heavy
landings led to very low prices and cod were sold as low as 1.20­1.40/kg
during this period. (Ireland: Discarding)
· As in 2007, vessels are now discarding 0­500g and 500­1kg monkfish to
meet quota restrictions. This discarding is reportedly at quite a high level,
particularly in around 200m400m. (Ireland: Discarding)
· Reports of problems with discarded longlines and gill nets along the Scot
tish west coast deep water grounds. A lot of longline activity reported at
south end Rockall plateau. (Scotland: Implications: Potential for gear con
flicts).
· Despite the closure of the hake gillnet fishery in Areas VIIbk in depths >
200m for part of 2006, and subsequent regulations introduced in 2007 that
restrict the length of gear and soak time in the hake fishery, Irish gillnet
fishermen reported that the 2007/2008 hake fishery was in fact quite poor
contrary to the scientific advice. Irish gillnetters tend to work in depths be
tween 200­300m. Many vessels switched back to trawling due to poor
catches and there are now only 7­8 gillnet vessels > 12m left in the fleet

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and 3­4 of these have applied for decommissioning reflected the poor re
turns in recent years. (Ireland: excessive gear lengths and soak times).
· Under Natura 2000, UKScotland has proposed a SAC on the Stanton
Banks off the northwest coast of Donegal in Area VIa. The proposed area,
which would be closed to trawling, dissects the grounds fished extensively
by Irish vessels. While the number of vessels working this area has de
creased in the last number of years to around 5 vessels (parttime) the im
pact would nonetheless be adverse. Through the NWWRAC a case has
been made to reduce the impact of this proposed closure (Ireland: Compli
ance with regulation).
· Bycatch of benthic fauna and several nontarget fish species (e.g. gobies) in
beam trawls. Voluntarily use of longitudinal release holes in the lower
panel of the trawl, which open when nets are filled with benthos, and of
Benthic Release Panels. Research is being carried out with the industry to
optimise a Benthic Release Panel for the Dutch beam trawling segment.
Similar initiatives in Belgium (Netherlands and Belgium: Implications: re
duced benthic impact).
· As reported in 2006 and 2007, management regulations in the scad fishery,
restricting the bycatch of mackerel to 5% has lead to widespread slipping
in the pelagic fisheries when catches have been mixed. This discarding is
reported to be substantial. There is also evidence of high grading in the
mackerel fishery as due to economic pressures vessels are only landing
mackerel of 300g+ and discarding catches of smaller fish. Again the levels
of discarding are quite high compared to actual reported landings (Scot
land: Implications: discarding).
· Norwegian trials estimated mortality of mackerel after crowding and slip
ping in purse seines has been continuing. Three trials were completed in
2007, crowding for 10­15 min, gave mortality rates of 80­100%. Work will
continue with herring in 2008 and a large project is planned for 2009,
which will also include new design of the purse seine, cooperation with
the industry (Norway: Implications: unaccounted fishing mortality).
· In Iceland changes in length distributions on the fishing grounds with lar
ger rates of small haddock reported in some areas. Due to the amount of
small haddock, Mls regulations were reduced from 45cm to 41cm. This
meant some closed areas were opened although many remained closed
due to high catch of small cod (<55cm) (Iceland: Implications: increased ef
fort on haddock stock).
· Following reduction in cod quotas but increased quotas for haddock, the
Icelandic fleet has begun targeting haddock with all demersal fishing
gears. Most vessels avoid catching cod, which is now taken as bycatch (Ice
land: Implications: increased effort on haddock).
· Some Icelandic gillnetters have shifted over to longlines. Exact numbers
are not known. This reduction has been a result of pressures over bycatch
of seabirds and small cetaceans. The level of bycatch is not known but is
felt to be quite high given the shifts in fishing method (Iceland: Implica
tions: reduced impact on marine mammal and seabird bycatch).
· One Norwegian vessel has carried out experiments using pelagic trawl
doors fished off the seabed (approx. 5 m) with a clump (weight) connected
50 m behind the doors to ensure proper bottom contact. This method is be

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ICES WGFTFB REPORT 2008
ing used to target demersal trawl fishing for gadoids in the Barents Sea but
with reduced seabed contact (Norway: Implications: reduced bottom im
pact).
· In the last years it is reported that there is a growing number of sea turtles
are accidentally caught by bottom and pelagic trawlers in the Central
Northern Adriatic Sea. It is estimated that in this area more than 4000 tur
tles per year are caught by trawls, longlines and bottom gillnets. Pelagic
sharks are also caught. No mitigation measures are currently enforced al
though research has been continuing (Mediterranean: Implications: By
catch of targeted species).
· In Italy there has been considerable experimentation with a new type of
beam trawl to replace the traditional Rapido trawl. This trawl is much
more environmental friendly gear and can reduce bottom impacts. Around
4/5 fishermen from the Central Adriatic coast are currently using this new
trawl design (Italy: Implications: reduced bottom impact).
Development of New Fisheries
· A new fishery has developed in Iceland for sea cucumber. This new fishery
has not significantly removed effort from other fisheries. But after a col
lapse in the scallop stock (Breiðafjörður 2003 Chlamys islandica) some
smaller fish boats previously targeting scallops have now shifted to the cu
cumber fisheries (Iceland: Implications: shift of effort from scallop fisher
ies).
· Up to eight of the pelagic vessels have continued to fish for boarfish
(Capros aper) during Q4 2007 and Q1 2008. Two vessels fished for this spe
cies in 2006 and approximately 8 vessels in 2007. With the very short fish
ing time now on all of the pelagic species this new fishery has been
identified as an opportunity to extend the vessels operating time. The fish
are suitable only for fishmeal production with a good quality oil content
(between 8­10%) but discharging from the vessels and handling in the fac
tories is proving very difficult with the discharge in particular an ex
tremely slow process. Nonetheless landings by Irish vessels have
continued to increase and are now probably in excess of 5,000­6,000 tonnes
valued at around 1 million. An initial biological study reports that fishing
effort has not had any significant impact on the stock but without man
agement measures the stock may come under pressure quite quickly given
it is a relatively slow growing pelagic species. (Ireland: Development of
new fishery for species with limited scientific data available).
· There has been an increase by Dutch vessels in Nephrops fisheries using
twin trawls. Outrigger trawls are also replacing beam trawls, or flyshoot
ing (seining) mainly for nonquota species such as red mullet and cuttle
fish. (Netherlands: Implications: These are not new fisheries but represent
new trend in Dutch fishing resulting in effort and target species shift. Full
implications not yet known).
· Squid fishery in Moray Firth continues to develop when species available
on grounds, using very unselective 40mm mesh. Not much takeup in 2007
due to few squid. (Scotland: Implications: 40mm mesh means potential
high bycatch of young gadoids esp. cod and haddock. This fishery may
provide an alternative outlet for the Nephrops fleet seasonally, and hence
reduce effort in that sector).

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· Despite poor results from experimental trials carried out in 2007 by BIM, a
potential fishery for deepwater rose shrimp is being explored by an Irish
vessel off the south west coast. This vessel has landed samples of frozen
rose shrimp from 400­800m using standard scarper trawls with 80mm
codend mesh size and is reportedly gearing up with two specially de
signed shrimp trawls with 32mm codend mesh size. (Ireland: Implications:
Effort in small mesh fishery with potential for high discards).
· There has been increased catches of squid reported at Rockall in Q2 of
2008. In previous years catches of squid had been much reduced on 1990
levels but one 34m/1200hp Irish vessel is now freezing squid on board.
This vessel is landing upwards of 2­3 tonne of frozen squid per trip in ad
dition to quantities of fresh squid caught on the last days of the trip. This is
becoming of increasing importance and as quotas become exhausted at
Rockall vessels will undoubtedly begin to target this fishery more. (Ireland:
Implications: targeting nonquota species).
· In France new pot fisheries for Nephrops, octopus, crawfish, whelk and
also for fish (dorado and conger) in coastal and continental slope waters
are being tried (France: Implications: Development of new fisheries).

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ICES WGFTFB REPORT 2008
Annex 8h: FTFB Report to GFCM
This report outlines a number of technical issues relating to fishing technology that
may impact on fishing mortality and more general ecological impacts. This includes
information recent changes in commercial fleet behaviour that may influence com
mercial CPUE estimates; identification of recent technological advances (creep); eco
system effects; and the development of new fisheries in the Mediterranean Sea.
It should be noted that the information contained in this report does not cover fully
all fleets engaged in fisheries; information was obtained from France and Spain.
Changes in Fleet Dynamics between 2006 and 2008
· In France there has been a shift by the Bluefin tuna purse seine fleet from
fishing areas off Balearic islands to Libyan and Eastern African waters
(France: Implications: Shift in effort).
· In France a targeted decommissioning programme for the Mediterranean
fleet began last year and has begun slowly to reduce the number of older
trawlers as well as some more modern vessels. The reduction in the num
ber of trawlers is estimated at 20%. This programme is also targeted at the
French tuna purse seiners and driftnetters. (France: Implications: Reduc
tion in overall effort).
· In France and Italy the ban on pelagic driftnets in the EC has forced the
small scale fleets involved to shift their activity to other techniques target
ing large pelagic species with longlines and purse seines by the Italian
fleets. Some French vessels have also shifted effort to demersal species
mainly hake and sole with gillnet and trammels nets. (France and Italy:
Implications: Shifts of effort that may have impacts on pressure stock spe
cies).
· In France there have been increasing attempts to develop pot and trap fish
ing particularly in non trawling areas and deep slope and reefs (France:
Implications: Use of more environmentally friendly fishing methods).
Technology Creep
· In France since 2006 a number of vessels have used high opening trawls to
target midwater fish such as hake, sea bream and sea bass. Some of these
vessels are using a specialist 4door rig with small pelagic doors mounted
on the top wings to open the trawl. This has been driven by market de
mand for these species (France: Implications: Increased efficiency).
· Recently some Italian bottom trawlers, mainly in the central and southern
Italian coasts have switched from single to twinrig trawling, and some
others have changed to a new "Atlantic" shapes named by the Italian fish
ermen: "Americana trawl" (Italy: Implications: Increased efficiency).
· The increase of fuel price has forced the French trawl fleets to reduce the
size of their gear and for some of them have shifted from high opening bot
tom trawl for hake to twin trawl for sole and monkfish (France: Implica
tions: Improved fuel efficiency).
· Both in Italy and France in the Mediterranean fisheries there has been in
creasing use of high specification sonars for pelagic gears and gear moni

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toring sensors for demersal trawls. (France and Italy: Implications: In
creased efficiency).
· Both French and Italian fishermen are increasingly fitting econometeres to
monitor fuel consumption and using thinner twines to reduce net drag.
Some vessels have also removed Kort nozzles to improve fuel efficiency
(France and Italy: Implication: Improved fuel efficiency).
· In Italian static gear fisheries there is increasing use of net stacking ma
chines decreasing setting time. Also there is increasing use of sewing ma
chines for mounting the headline and leadline reducing construction times
(Italy: Implications: Improved operating efficiency).
Technical Conservation Measures
· In the Mediterranean new EU regulations have been introduced requiring
the use of 40mm square mesh codends. The implications are not known at
present but in Italy this represents a large increase in mesh size from
codend mesh sizes currently used. Other regulations are planned to limit
fishing effort through limitations on bollard pull and on gear size by re
stricting the headline length and trawl circumference; limiting the number
of hooks for longlines and maximum lengths for static nets. (Italy and
France: Implications: Not known but potentially increased selectivity).
· In France enforcement of new EC regulations for the Mediterranean sea
has meant French Mediterranean trawlers replacing their illegal but widely
used 28 or 35 mm mesh codends with legal 40 mm diamond mesh codends
(France: Implications: Improved selectivity).
· There has been increasing efforts by French vessels in the Mediterranean to
target small hake because of market demand but this conflicts with the
new Mediterranean regulations in terms of mls and may well have an im
pact on the French fleet (France: Implications: Potential discard problems if
mls regulations are enforced).
Ecosystem Effects
· In the last years it is reported that there is a growing number of sea turtles
are accidentally caught by bottom and pelagic trawlers in the Central
Northern Adriatic Sea. It is estimated that in this area more than 4000 tur
tles per year are caught by trawls, longlines and bottom gillnets. Pelagic
sharks are also caught. No mitigation measures are currently enforced al
though research has been continuing (Mediterranean: Implications: By
catch of targeted species).
· In Italy there has been considerable experimentation with a new type of
beam trawl to replace the traditional Rapido trawl. This trawl is much
more environmental friendly gear and can reduce bottom impacts. Around
4/5 fishermen from the Central Adriatic coast are currently using this new
trawl design (Italy: Implications: reduced bottom impact).
Development of New Fisheries
· In France new pot fisheries for Nephrops, octopus, crawfish, whelk and
also for fish (dorado and conger) in coastal and continental slope waters
are being tried (France: Implications: Development of new fisheries).

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160 |
ICES WGFTFB REPORT 2008
Annex 9: Compendium of Mitigation Technologies
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Active
Pingers
Gillnets
porpoises
Cetaceans
US, EU,
effective
Required

Larsen, 1999;
acoustic
Mediterranean
Kraus 1997
devices
Gillnet fisheries
Active
Pingers
Driftnets
sea lions
Pinnipeds
California
Effective
Required

Barlow &
acoustic
swordfish and
Cameron 2003
devices
sharks fishery
Active
Pingers
Gillnets
harbour
Pinnipeds
Washington
Ineffective
Required

Gearin et al., 2000
acoustic
seals
salmon and
devices
sturgeon fishery
Active
Pingers
Gillnets
Franciscana
Cetaceans
Argentinian
reduced


Bordino et al.,
acoustic
river
fishery
bycatch but
2002
devices
dolphin
dinner bell for
sea lions
Active
Pingers
Bottom
dugongs
Dugongs
Australian
Inconclusive
Not

Anon., 2003
acoustic
trawl?
fishery
required
devices
Active
Pingers
Fish traps
Humpback
Cetaceans
Newfoundland
Effective


Lien et al., 1992
acoustic
whale
cod and pollack
devices
Active
Pingers
Gillnets
Hectors
Cetaceans
New Zealand
Effective


Stone et al., 1997
acoustic
Dolphin
fishery
devices
Active
Pingers
Gillnets
Common
Birds
Puget sound
Not significant

Reduced
Melvin et al., 1999
acoustic
Murre,
salmon, NW US
bycatch of
devices
Rhinoceros
Pacific
Common
auklet
Murre, but not
the Rhinoceros
auklet

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ICES WGFTFB REPORT 2008
| 161
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Active
Pingers
Gillnets,
Bottlenose
Cetaceans
Mediterranean
Inconclusive &
Not


acoustic
longline
Dolphins,
Sea
inconsistent
required
devices
harbour
porpoise
Active
Modified/Interactive
Pelagic
Common
Cetaceans
IRL, DM, FR
Inconclusive &
Not

Anon., 2006
acoustic
Pingers
trawls
dolphins
pelagic trawls
Inconsistent
required
devices
bass albacore,
bowriding
Active
Modified/Interactive

Bottlenose
Cetaceans
IRL,
Effective
Not

Leeney et al., 2007
acoustic
Pingers
Dolphins
Bowriding
required
devices
experiments
Active
Oil Filled tubes
Purse Seine
Dolphins
Cetaceans
Japanese and
Short term,


SGFEN, 2001.
acoustic
Tunisian
followed by
devices
fisheries
habituation
Active
pyrotechnics

killer whales
Cetaceans
Alaska Sablefish
Ineffective
Illegal
Also ineffective
Dahlheim, 1998
acoustic
for California
devices
Sea Lion
Active
Transponder signaled
Trawls



Operationally
Not

Pennec &
acoustic
closed codends
possible, yet to
required
Woerther, 1993
devices
be tested in sea
trials
Active
Arcdischarge
Trawls,
fur seals
Pinnipeds
South Africa
Some effect in


Shaughnessy et
acoustic
transducer
Purse
Hake fishery
trawls, Not
al., 1981
devices
Seines
effective in P.
seines
Active
AHDs
Gillnets,
harbour seal,
Pinnipeds
Oregon Salmon
Worked for
Ineffective

Geiger &
acoustic
trawls
fur seals
fishery, New
porpoises in
Jefferies, 1987;
devices
Zealand hoki
Bays in British
Stewardson &
Columbia
Cawthorn, 2004

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162 |
ICES WGFTFB REPORT 2008
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Active
Predator sounds
Area tests
Gray whale
Cetaceans
California Coast,

effective

Cummings &
acoustic
(Killer whales)
Beluga
Alaska, Japan
Thompson 1971;
devices
whale Dall's
Fish & Vania
Porpoise
1971; Jefferson
and Curry, 1996
Active
Predator sounds
Purse
California
Pinnipeds
Washington
Scordino &
Ineffective

Cummings &
acoustic
(Killer whales)
Seine?
Sea Lion
Pfeifer, 1993
Thompson 1971;
devices
Fish & Vania
1971; Jefferson
and Curry, 1997
Active
AHDs
Traps and
Grey Seal
Pinnepeds
Baltic Sea

Not
Mixed results.
Fjalling et al.,
acoustic
gillnets
required
Testing driven
2006
devices
by increasing
predataion by
seals
Active
Pingers
Gillnets
Grey Seal
Pinnepeds
Baltic Sea

Ineffective
Negative
Stridh, 2008
acoustic
results. Dinner
devices
bell and
increased
predation
observed
Alternative
Break away lines, light
Traps and
Northern
Cetaceans
US and Canada
more data


Werner et al.,
buoy ropes
messenger ropes, glow
Gillnets
Right whales
fisheries
required
2006
ropes, acoustic
triggers

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ICES WGFTFB REPORT 2008
| 163
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Bait & Lure
Dyed bait (blue)
Longlines
albatross
Birds
Hawaiian
Effective


McNamara,
Alterations
spp
swordfish/tuna
1999 ; Boggs, 200;
Gilman et al.,
2003a
Bait & Lure
Dyed bait (blue)
Longlines
loggerhead,
Turtles
Costa Rica,
Ineffective


Swimmer et al.,
Alterations
leatherback
West Atlantic
2005 ; Watson et
turtles
al., 2002
Bait & Lure
Weighted Bait
Longlines
albatross
Birds
Atlantic
Effective


Boggs, 2001
Alterations
spp
swordfish
Bait & Lure
Novel Bait switch to
Longlines
loggerhead,
Turtles
Atlantic
No effect

Noxious bait no
Watson et al.,
Alterations
mackerel
leatherback
effect on
2005
turtles
California Sea
Lion either
Bait & Lure
Streamer Lines &
longlines
albatross
Birds
Hawaiian
effective


Boggs, 2001;
Alterations
towed buoys
other
swordfish,
Lokkeborg, 2001;
seabirds
Norwegian
McNamara et al.,
Longline
1999
Bait & Lure
Circle Hooks
Longlines
turtles
Turtles
Global Longline
effective but
Required in
Other: Deeper
Gilman et al.,
Alterations
fisheries
may increase
some
sets, single bait
2005 ; Gilman et
shark catches
instances
hooking,
al., 2006 ; Watson
minimising day
et al., 2004
soak time,
Bait & Lure
Circle Hooks
Longlines
Turtles
Turtles
Mediterranean
Some success
Not
Experimental
FTFB, 2008
Alterations
Sea
with circle
required
stage
hooks
Exclusion
TEDs
Trawls
turtles,
Turtles
Global Shrimp
extremely
Required

Clark et al., 1991;
Devices
sharks, rays
fisheries
effective
Shiode and Tokai,
2004

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164 |
ICES WGFTFB REPORT 2008
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Exclusion
TEDs
Bottom
Turtles,
Turtles
Mediterranean
Effective at
Not
Experimental
Sala et al., 2008
Devices
trawls
sharks, rays
Sea
reducing turtle
required
and needs
(project LIFE 04
bycatch and
further
NAT/IT/000187)
reducing
development
and E.Taskavak
debris. Losses
and S. Atabey
of marketable
(Turkish study)
fish a problem
Exclusion
TEDS
Shrimp
Turtles
Turtles
Cameroon
Not yet
Proposed
Experimental

Devices
trawls
evaluated
but extensive
testing of super
shooter, double
flap cover.
Exclusion
TEDS
Shrimp
Turtles
Turtles
Nigeria

Required
Big incentives in

Devices
trawls
(Super
US market
shooter,
certification;
double flap
socioeconomic
cover) US
effects need to
certified
be studied
Exclusion
TEDS
Shrimp
Turtles
Turtles
Mexico
Effective in
Required


Devices
trawls
reducing turtle
(Super
bycatch
shooter,
double flap
cover) US
certified
Exclusion
TEDS
Shrimp
Turtles
Turtles
Venezuela
Effective in
Required
50% of
Marcano et al.,
Devices
trawls
reducing turtle
(Super
commercial
1998.
bycatch
shooter,
catch is lost
double flap
through the use
cover and
of TEDs
single cover
net) US
certified

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ICES WGFTFB REPORT 2008
| 165
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Exclusion
TEDS
Shrimp
Turtles
Turtles
Columbia
Effective in
Required
Big incentives in

Devices
trawls
reducing turtle
(Super
US market
bycatch
shooter,
certification;
double flap
socioeconomic
cover) US
effects need to
certified
be studied; 20­
40% loss of
marketable fish
catch
Exclusion
TEDS
Shrimp
Turtles
Turtles
Costa Rica
Effective in
Required
Big incentives in

Devices
trawls
reducing turtle
(Modified
US market
bycatch
Super
certification;
shooter
socioeconomic
with a
effects need to
separation
be studied
between
bars of 6
inch, double
flap cover)
US certified
Exclusion
TEDs
Shrimp/Fish
Turtles
Turtles
Trindad &

Not
Extensive

Devices
Trawls
Tobago
required
experimentation
with different
designs
Exclusion
TEDs
Shrimp/Fish
Turtles
Turtles
Bahrain

Not
Extensive

Devices
trawls
required
experimentation
with different
designs

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166 |
ICES WGFTFB REPORT 2008
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Exclusion
TEDs
Shrimp/Fish
Turtles
Turtles
Iran

Required


Devices
Trawls
(super
shooter,
double flap
net cover &
AUSTED)
Exclusion
TEDs
Shrimp
Turtles
Turtles
Indonesia

Required


Devices
trawl
(super
shooter,
double flap
net cover)
US Certified
Exclusion
TEDs
Shrimp
Turtles
Turtles
Southeast Asia
Effective in
Required


Devices
trawls
(Thailand)
reducing turtle
(TTFD); US
bycatch
certified
Exclusion
TEDs
Shrimp
Turtle,
Turtles
Madagascar
Effective in
Required
Big incentives
Report on TED
Devices
trawls
sharks, rays
reducing turtle
(Super
following
implementation
bycatch;
shooter,
certification by
to the fishermen's
double flap
US.
association
cover); US
Certified
Exclusion
TEDs
Shrimp
Turtles,
Turtles
French Guyana
Effective in
Proposed


Devices
trawls
sharks, rays
reducing turtle
(Nordmore
bycatch
grid, double
flap net
cover)
Exclusion
TEDs
Shrimp
Totoaba
Fish
Upper Gulf of
Effective in
Required in
Bycatch
Managament
Devices
Trawls
mcdonaldi
California
reducing turtle
MPA (Fish
reduction of
plan for fishing
(Mexico)
bycatch
eye)
40%
in the Upper Gulf
of Claifornia
(Mexico)

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ICES WGFTFB REPORT 2008
| 167
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Exclusion
SEDs
Pelagic
fur seals, sea
Pinnipeds
Australia, NZ,
effective, esp.
Required ?

Gibson and
Devices
Trawls
lions
Tasmaina, squid,
with top
Isaken, 1998;
hoki, blue
escape hatch in
Cawthorn &
grenadier
large mw
Starr, in prep;
fisheries
trawls
Anon., 2003.
Exclusion
REDs (Rigid)
Pelagic
Common
Cetaceans
UK Bass, French
inconclusive
Not

Anon., 2006
Devices
Trawls
dolphins
albacore
required
fisheries
Exclusion
Net panels
Pelagic
Common
Cetaceans
Dutch N. Africa,
Inconclusive,
Not

Anon., 2006
Devices
trawls
dolphins,
UK and FR Bass
difficult to
required
other MF off
fisheries
handle, major
Africa
loss of target
species
Exclusion
Net panels
Purse Seine
dolphins
Cetaceans
Eastern Tropical
effective

Called the
Werner et al.,
Devices
Pacific yellowfin
Medina panel
2006
tuna fishery
Exclusion
Turtle chains/modified
Scallop
turtles
Turtles
US scallop
effective


Smolowitz, 2006
Devices
dredges
dredge
fisheries
Exclusion
Trap guards (bungee
Traps
bottlenose
Cetaceans
Indian River
effective


Noke and Odell,
Devices
cord)
(crabs)
dolphins
Lagoon
2002
Operational
Night Sets
Longlines
seabirds
Birds
Hawaii fishery
effective


McNamara et al.,
Practices
1999; Boggs, 2003
Operational
Side Sets
Longlines
Albatross
Birds
Hawaiian
effective


Gilman et al.,
Practices
spp
swordfish/tuna
2003a; Gilman et
Western North
al., in press;
Pacific
Yokota and
Kiyota, 2006

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168 |
ICES WGFTFB REPORT 2008
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Operational
Underwater Sets
Longlines
seabirds
Birds
Hawaiian tuna,
effective

Increased catch
Lokkeborg, 2001;
Practices
(chutes)
Norwegian
rate for target
Gilman et al.,
Longline
species
2003 b
Operational
Underwater Sets
Gillnets
Bottlenose
Cetaceans
North Australia
effective


Hembree &
Practices
(subsurface)
and Long
multi species
(reduction
Harwood, 1987
snouted
~50%)
spinner
Operational
Discarding offal
Longlines
Albatross
Birds
Hawaiian
effective

Distracted the
McNamara et al.,
Practices
during shooting
spp
swordfish/tuna
birds so
1999
presume was
effective?
Operational
Time area closures
Gillnets
Hectors
Cetaceans
New Zealand
highly
Required

Read et al., 2006
Practices
Dolphins
fisheries
effective
Operational
Decoys (anchored
Static Gears
Grey Seal
Pinnepeds
Baltic
Short term
Not

Fishermen's
Practices
boats)
effects noted
required
Information
Operational
Dropping headline of
Pelagic
Small
Cetaceans
NE Atlantic/Bay
Not assessed
Voluntary
Main
NECESSITY
Practices
pelagic trawls
Trawls
cetaceans
of Biscay
motivation is to
project
target larger
tuna
Passive
Reflector devices

small
Cetaceans
SA Beach
effective for
Not

SGFEN, 2001.
acoustic
cetaceans
protection
short period
required
devices
Passive
Reflector devices
Gillnets
porpoises
Cetaceans
EU gillnet and
Tested in
Not


acoustic
(Aquatec)
tangle net
Albacore tuna
required
devices
fisheries
fishery but
inconclusive
results

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ICES WGFTFB REPORT 2008
| 169
Mitigation
Specific Device
Fishing
Species Species Test forum
Performance
Regulatory
Comments References
Methods
Gear
Category
status
Passive
Reflector devices,
Gillnets,
Bottlenose
Cetaceans
NZ Gillnets,
metallic head


Hembree &
acoustic
metallic heads,
float lines
Dolphins,
Simulated
ineffective,
Harwood, 1987;
devices
barriers
porpoises
gilllnets
Scotch exp.
Goodson &
Scotland, float
Effective,
Mayo, 1995;
lines Canada
Porpoises
Koschiski &
ineffective
Culik 1997
Passive
Reflector nets
Gillnets
porpoises
Cetaceans
Bay of
mixed results,
Not
Use with
Koschinski et al.,
acoustic
barium/iron oxide
Fundy,Canada
generally
required
pingers/TADs
2006; Larsen et
devices
fisheries, North
effective, but
recommended,
al., 2007 ; Trippel
Sea,
not in UK
also effective for
et al., 2003,
North Sea
Shearwaters in
Northridge et al.,
Canada
2003
Passive
Echolocation
Gillnets
bottlenose
Cetaceans
Mediterranean
promising, but
Not

Werner et al.,
acoustic
disruptors
dolphins
fisheries
habituation
required
2006
devices
may occur
Twine
Multimonofilament,
Gillnets
porpoises
Cetaceans
North Sea and
multi mono

thinner twine
Northridge et al.,
alterations
Thinner twines
West of Scotland
ineffective
also effective for
2003
fisheries
thinner twine
seals
effective for
porpoises and
seals
Twine
White Mesh
Gillnets
Common
Birds
Puget sound
Effective
Some
Some
Melvin et al., 1999
alterations
Mure,
salmon, NW US
reductions
reductions in
Rhinoceros
Pacific
in salmon
salmon landings
auklet
landings

---

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ICES WGFTFB REPORT 2008
| 171
Annex 10: Loggerhead Turtle (Caretta caretta) bycatch, case study:
Mediterranean Sea
Alessandro Luchetti and Antonello Sala, ISMARCNR, Ancona, Italy
There are three turtle species in the Mediterranean Sea: the leatherback (Dermochelys
coriacea), the green (Chelonia midas) and the loggerhead turtle (Caretta caretta).
Loggerhead sea turtles are listed as endangered in the Red List of Threatened Species
of the International Union for Conservation of Nature and Natural Resources (IUCN;
HiltonTaylor, 2000). The Barcelona Convention adopted an Action Plan for the Con
servation of Mediterranean Marine Turtles in 1989, acknowledged that catches by
fishermen are the most serious threat to turtles and that their conservation deserved
special priority (Tudela, 2000). In the Mediterranean Sea, they represent the most
abundant species of marine turtles. Moreover C. caretta is one of the two marine turtle
species with nesting beaches in the Mediterranean Sea; Broderick et al. (2002) esti
mated that there are 2.280­2.787 loggerheads nesting annually in the Mediterranean.
Laurent et al. (1992) considered that adult survival as the main factor affecting popu
lation growth rates, fecundity being less significant; this emphasizes the importance
of limiting fishing bycatch of these species.
The knowledge of the biology of the loggerhead turtle represents a crucial part in
evaluating the impact of different fishing activity in different areas. In the Mediterra
nean sea it is possible to count ten different countries with nesting beaches (Cyprus,
Egypt, Greece, Israel, Italy, Lebanon, the Libyan Arab Jamahiriya, the Syrian Arab
Republic, Turkey and Tunisia), but probably the Eastern Mediterranean sea (Greece
and Turkey) represents the most important area. Furthermore it is possible to define
two main ecological phases in the loggerhead turtle's life: the pelagic phase and the
demersal phase. The greatest density of specimens in the demersal phase is found in
shallow waters (< 100m). Thus, different types of fishing gear can produce different
capture and mortality rates and may affect different ecological phases (pelagic or
demersal; Gerosa and Casale, 1999). In the Mediterranean, interactions of sea turtles
with fishing gears, including trawl nets, are still insufficiently studied (Casale et al.,
2004). Surface longline, driftnet and bottom trawl boats operating in the Mediterra
nean are the major threats to the survival of this species, even if the impact of fixed
gears (gillnets and trammel nets) needs also to be carefully considered.
Several countries (22 Mediterranean and 15 nonMediterranean) fish normally in the
Mediterranean Sea and an undefined number of small boats are active in nonEU
countries but reported levels are not recorded. Thus the fishing effort in this area is a
key factor in considering turtle bycatch levels.
Caminas (2004) reports a possible direct exploitation of loggerhead turtle mainly in
the North Africa countries and an illegal market probably exists in Egypt. Neverthe
less the main threat for the conservation of C. caretta population in the Mediterranean
Sea remains bycatch in fishing gears.
Mediterranean fisheries have a huge impact on the turtle stock: more than 60.000 tur
tles are estimated to be caught annually as a result of fishing practices, mortality rates
ranging from 10 percent to 50 percent of individuals caught (Lee and Poland, 1998).
Delayed mortality is mostly unknown.
Bottom trawling activity mainly impacts turtles in the demersal phase since they pre
fer the shallow waters of the North Adriatic Sea, South Turkey, Tunisia and Egypt. It

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172 |
ICES WGFTFB REPORT 2008
is possible to estimate annual catch of over 4.000 specimens in the centralnorthern
Adriatic Sea (Casale et al., 2004), 2.500 (Bradai, 1992) to 5500 (Jribi et al., 2004) in the
Gulf of Gabés (Tunisia) and high unreported catches in Turkey and Egypt (Laurent et
al., 1996). The main factors affecting the bycatch of loggerhead turtle are:
· the fishing area: mainly in shallow waters;
· the period of the year: most of catches are obtained in winter (Casale et al.,
2004), during the demersal phase (foraging areas); and
· the haul duration which affects the physical condition of the turtle. Indi
viduals have been observed in a comatose state and other nonhealthy
specimens (dead or injured) observed due to long haul durations in bot
tom trawl fisheries (Casale et al., 2004; Casale et al., 2007).
The surface longline gear deployed over the continental shelf (for tunalike species)
or offshore waters (for swordfish, albacore and bluefin tuna) is considered as the
main threat to marine turtles in the Mediterranean (Margaritoulis et al., 2003). Panou
et al. (1992) estimated an annual catch of about 35.000 specimens alone for the west
ern and central Mediterranean Sea.
Some studies investigating the Spanish longline fleet targeting swordfish in the South
Western Mediterranean (up to 60­80 vessels in the summer months, in the early
1990s) suggested that turtle bycatches in this region are very high (Aguilar et al.,
1995). From 22.000 to 35.000 individuals per year were estimated to be caught in the
period 1990­91. Bycatch by the foreign industrial longline fleets operating in the area
(Japanese, flag of convenience) could have led to even higher figures. Data on annual
catches are also available for other countries (Italy, Morocco, Tunisia, Malta, Algeria,
and Greece) but in some cases there is a concern over the validity of the data. More
over no data are collected in some countries at all.
The main problems with longline fisheries are that 20­30% of the turtles caught by
longline gear may die (Aguilar et al., 1993). 80% of turtles hooked are released alive
but with the hook still inside the mouth, pharynx or oesophagus (Camiñas and Valei
ras, 2000), and the eventual delayed mortality is unknown although expect to be
high.
Fishermen agree on the important economic losses due to turtle interactions with
longlines. Loss of hooks, bait, branch lines and other components of the gear are an
economic problem that fishermen want to solve. The capture of sea turtles also pro
duces a decrease in the fishing effort and yields, as a consequence, of the reduction in
the number of hooks and the time necessary to repair or replace gear.
Concerning other fishing gears, few official and published data are available. For
drift nets bycatch was estimated by Italian drift nets in Ionian Sea at around
16.000/year; (De Metrio and Megalofonou, 1988). Illegal drift nets are still widely
used in many countries, and the amount of bycatch is estimated to be very high.
Moreover several driftnet vessels from EU countries were sold to nonEU countries,
mainly Moroccan fleets, shifting the bycatch problems from the north to the south
basins.
Turtle captures seem to be also high in passive gears, such as fixed nets; gillnets and
trammel nets. Captures by these gears cause direct mortality since turtles get caught
in them when trying to feed and are entrapped and drown. Fixed nets represent a
threat for sea turtles mainly in coastal areas (Lazar et al., 2004a), however, quantifica
tion of turtle captures in these widely spread fisheries is very difficult to assess and
juveniles are frequently caught nearby nesting areas in Greece, Turkey and Cyprus

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(Godley et al., 1998; Suggett and Houghton, 1998). Fixed nets probably are responsi
ble for high mortality rates. Delaugerre (1987) reported a mortality rate of 94.4% for
C. caretta specimens caught in Corsica by trammel nets placed at depths of more than
60 m. Argano et al., 1992 found that the mortality rate for specimens tagged and then
recaptured by set gill nets in different countries was 73.7%. Lazar et al., (2004b) re
corded a high mortality rate (62.5%) for turtles captured in gill nets in Adriatic. Thus
in the Mediterranean the interaction of sea turtles with the static net fishery could be
very important and comparable to other fisheries (Casale et al., 2005).
Purse seines seem to represent a minor problem for turtles since the annual catches
are probably very low and any turtles caught are released alive, but further investiga
tion are required to verify this assumptions
Different approaches should be taken into account in reducing the bycatch of logger
head turtle including:
· gear modifications;
· effort reductions;
· time closures;
· protected areas and sanctuaries (i.e. in nesting areas);
· changes in fishing tactics (i.e. reduction of haul duration can reduce direct
mortality; set longline in depth etc.); and
· better cooperation and education of fishermen (i.e. keeping the turtles on
board and allowing them to recover before releasing them or removing the
hooks from turtle's mouth etc.)
Concerning gear modifications in bottom trawls, very few studies have been carried
out in the Mediterranean Sea. Sala et al. (unpublished results, ongoing project LIFE 04
NAT/IT/000187) developed and tested at sea four different types of TEDs (Turtle Ex
cluder devices). The main goal of these tests were to implement the TEDs in order to
show that they can be used with minimal losses of target species while also providing
benefits to fishermen in terms of reduced sorting time. The first attempts were not
satisfactory because the debris (mainly stones) caused damage to the grid or the
commercial losses were too high. Other grid designs were tested and step by step the
performances of TEDs were improved. A flexible but resistant TED made of steel and
rubber showed a good effectiveness in reducing bycatch, and debris, and turtles, with
no commercial losses, and this seemed to be a good solution. Finally a Supershooter
TED was tested and very good results were obtained in reducing discards and in re
leasing turtles, even if the setting the angle of the grid was difficult. Atabey and
Taskavak (2001) tested the Supershooter TED in the shrimp fishery off Turkey. They
obtained very good results because both C. caretta and Chelonia mydas were excluded
by the modified Supershooter, and unwanted incidental catches, such as jellyfish,
sharks, and rays could also be excluded. They also found that most turtle catches oc
curs at the depths between 11 and 30 meters and that the proportion of dead and co
matose turtles resulting from trawls increased with towing time. The final
recommendation of the authors was that modified Supershooter TEDs could greatly
assist fishermen in reducing catches of turtles and unwanted bycatch without losing
valuable prawns or fish.
Considering longlines the main factors affecting sea turtle bycatch are:
· number of hooks;
· hook size and shape: J shape and circle shape;

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· hook material: some observations seem to point to a rapid degradation (2­
3 months) of nonstainless hooks in the mouth of the turtles released
(Panou et al., 1999);
· bait type: catch rates of loggerhead turtles are higher with squid baits than
with fish baits, use of lightsticks;
· bait colour: differences between bluedyed baits and nondyed baits;
· fishing depth: depth at which the branch line is positioned;
· location of fishing grounds in relation to the topographic and oceano
graphic features, sea temperature; and
· total catch: higher catches sink the gear and increase turtle mortality.
One of the most important mitigation measures tested in the southern Italian longline
fisheries is the change in hook shape (project Life Nature 2003 ­ NAT/IT/000163).
Some studies have tested the effectiveness of circle hooks in comparison to J shape
hooks and found that no significant differences in catch efficiency on the target spe
cies (swordfish) was observed; turtle bycatch was observed only in J shape hooks;
and also the circle hook showed good efficiency in avoiding the bycatch of pelagic
stingray Dasyatis violacea. Tests carried out in the Strait of Sicily seemed to confirm
these results: 82% of turtle were caught with J shape hooks, while only 18% with cir
cle hooks. Furthermore 88.2% of the turtles were caught in the mouth, while 11.8%
swallowed the hooks: all swallowed hooks were J type. Finally also in this case no
differences were found in the number and total weight of target swordfish captured.
The influence of different bait types in the bycatch of loggerhead turtle was also in
vestigated. In the Western Mediterranean sea some authors found that the combina
tion of hook and bait type resulted in the lowest bycatch of turtles and the highest
catches of swordfish was with J hooks with mackerel bait (project FISH/2005/28A,
2008). In the Alboran Sea some authors found that the use of mackerel bait can effec
tively reduce incidental capture of loggerhead sea turtles compared to squid bait. A
total of 38 loggerhead turtles were caught, 27 (71%) were caught on squid while 11
(29%) on mackerel bait. Also in this case there were no significant differences be
tween the numbers of individuals or weight of target species (swordfish) between the
2 bait types.
In the Ionian Sea "size of hook" was studied (Deflorio et al., 2005). The main result
was that the smaller hooks used for albacore tuna fishing are more likely to catch tur
tles as they are easier for the turtles to feed on them.
Acoustic deterrent experiments were carried out on 4 juveniles and 7 subadults of
loggerhead turtles in open tanks at the Cattolica (Italy) "Delphynursery". At frequen
cies between 50 and 400 Hz, some avoidance behaviour was observed with the
maximum level of avoidance at (20%) 50Hz. A "neutral" behaviour (turtles reacting
to the sound but not moving towards or away from its source) was observed between
50 and 700 Hz with highest levels (40%) between 50 and 100 Hz. The most frequent
behaviour at all frequencies was "no response" and at frequencies above 700 Hz, no
response was observed in any of the tests. This results, even if based on a small sam
ple, together with the increased level of acoustic pollution in the Mediterranean did
not lead to further experiments.
The effect of bait colours (yellow, red and blue) and bait odour was tested with ex
periments carried out with 27 loggerheads (22 immature and 5 adults) in open tanks.
Juveniles reacted to baits colour differently compared to subadults and furthermore,
subadults showed distinctive individual differences in behaviour. As the reaction to

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different colours depended strongly on individual age as well as other factors, such
as smell, it was concluded it was not worthwhile to continue with these tests. More
over, it is very difficult to see how this solution could be adopted as a mitigation
measure, also because of problems associated with absorbance of colours with depth.
These experiments were conducted within the confines of shallow pools where there
was very little light attenuation.
Some studies were performed to evaluate the effect on sea turtle bycatch with the
setting depth of longlines. Increasing the set depth for longlines has been found to
reduce the overall catch rates of turtles. In the Ionian Sea preliminary results (project
Life Nature 2003 ­ NAT/IT/000163) seemed to indicate that most seaturtle bycatches
happened when hooks were set at between 10 and 15 m deep, however, more data is
needed to confirm whether this is a significant result. Other studies (Laurent et al.,
2001) showed that the maximum depth at which the marine turtles were caught was
60 m for swordfish longline and 20 m for albacore longline. There are concerns
though that the deeper setting of longlines may result in an increase in mortality rate
of turtles that are hooked and die through drowning.
The final consideration on mitigation measure can be summarised as follows:
TEDs:
TEDs represent a good solution in bottom trawls provided they are set optimally for
the trawls used. This has proved very difficult in Mediterranean Sea where even very
small species are marketable. Reduction of haul duration may also be an effective
operational measure for reducing direct mortality and occurrence of injuries as well
as weak and comatosed individuals
Circle hooks:
With circle hooks the following has been concluded:
· circle hooks show good efficiency in reducing bycatch of turtles and throat
hooking but some differences in fishermen's attitude to them were ob
served: circle hooks are not accepted by Spanish fishermen (Baez et al.,
2006) as their use is considered to diminish yields of target species (Gilman
et al., 2006). On the contrary Italian fishermen did not find any appreciable
difference (project life nature 2003 NAT/IT/000163).
· Circle hooks seem to shift the bycatch problem from turtle to cetacean and
shark (Caminas and Valerias, 2001).
· Casale (2005) reviewed the available data presented by Watson et al. (2003,
2004); the conclusion was that the overall effect of the circle hooks in re
ducing bycatch is largely limited to the softshelled leatherback turtle.
· Studies with loggerhead turtle carried out by NOAA in the Atlantic
strongly suggest that catch rate of these species is affected more by hook
size and bait and not so much by hook shape.
· When considering hook design as a mitigation measure one should keep in
mind the effects on catch rates for target species (fish) and bycatch of fish.
The SGRST/SGFEN 05­01 (2005) evidenced that, in a given fishery and
area, circle hooks (compared to Jshaped hooks): decreased the catch of
swordfish; increased the catch of bigeye tuna and bluefin tuna; and did not
affect the catch of blue sharks (research in Azores found that there was an
increase in blue shark catches; Bolten and Bjorndal, 2003)

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ICES WGFTFB REPORT 2008
· In a recent review on the efficacy of circle hooks in reducing sea turtle
mortality Read (2007) concluded that "circle hooks have the potential to
reduce the mortality of sea turtles captured in many (but not all) pelagic
longline fisheries, but that they should be field tested in a rigorous experi
ment before they are required in any fishery"
· Efficiency of hook shape seems to vary depending on target species and
fishing areas, thus according to the results reported for this specific fishery,
the consequences of the hook type to target species and the other sea tur
tles should be considered before introduction of mitigation measures.
Acoustic deterrent:
Results did not encourage continuation of this type of experiments for sea turtles
catch mitigation (SGRST/SGFEN 05­01)
Dyeing bait:
Although effective in laboratory experiments with captive turtles, dyeing bait does
not appear to have potential as an effective mitigation measure to reduce sea turtle
bycatch in longline fisheries (Swimmer et al., 2005).
Type of bait:
The use of mackerel bait can effectively reduce incidental capture of loggerhead sea
turtles as compared to squid bait and no significant differences were observed with
target species catch. Lightsticks used in swordfish fisheries were found to strongly
attract turtles.
Tank test:
The importance of physical factors (light penetration and colour absorbance, currents,
oceanographic factors, etc.) of atsea conditions should be taken into consideration in
analysing the results from experiments on captive animals, particularly with respect
to colour and odour, but also the isolation of a single turtle in a captive environment
is another important factor as it may affect behaviour. Tank tests results should be
considered with caution.
Bait size:
It is another important factor to be taken into account, but reliable information is not
available to assess whether this is significant or not is not available.
Set depth:
Increasing the set depth for longlines has been found to reduce the overall catch rates
of turtles but has led to increased mortality of turtles that are still hooked and subse
quently die through drowning. Swordfish longlines catch turtles at a depth between 0
to 60m; albacore longline catch turtles between 0 and 20m
Set nets:
Mainly in Turkey and Greece, avoiding areas known to have high turtles abundance,
which might occur seasonally (i.e. after nesting) could be a good avoidance practice.
Using gillnets instead of trammel net could also reduce entanglement of turtles. In
the Mediterranean the interaction and bycatch of sea turtles with the static net fishery
could be very important and comparable to other fisheries (Casale et al., 2005).

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Fishermen cooperation:
Comatose specimens can survive or die, depending on the circumstances. If released
immediately these turtles would probably die, because they cannot swim to the sur
face to breathe. Fishermen can substantially reduce this problem by keeping the tur
tles onboard and allowing them to recover before releasing them. Fishermen
cooperation and education is also essential in removing the hooks from the turtle's
mouth.
References
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en el Mediterráneo. Greenpeace. Proyecto internacional.
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gerhead sea turtle Caretta caretta population in the western Mediterranean. In J.I. Richard
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Argano, R., Basso, R., Cocco, M., Gerosa, G. 1992. New data on loggerhead (Caretta caretta)
movements within Mediterranean. Boll. Mus. Ist. Biol. Univ. Genova, 56­57:137­163.
Atabey, S., Taskavak E., 2001. A preliminary study on the prawn trawls excluding sea turtles.
Urun. Derg./J. Fish. Aquat. Sci. Vol. 18, no. 1­2, pp. 71­79. 2001.
Báez, J.C., Camiñas, J.A., Rueda, L. 2006. Accidental fishing capture of marine turtles in South
Spain. Mar Turtle Newsletter, 111:11­12
Bolten, A.B., Bjorndal, K.A., 2003. Experiment to evaluate gear modification on rates of sea tur
tle bycatch in the swordfish longline fishery in the Azores ­ Phase 2. Final Project Report.
NOAA Award Number NA16FM1378. ACCSTR. 19 pp.
Bradai, M.N. 1992. Les captures accidentelles de Caretta caretta au chalut benthique dans le
Golfe de Gabés. Rapp. Comm. int. Mer Médit. 33: 285.
Broderick, A.C., Glen, F., Godley, B.J., Hays, G.C. 2002. Estimating the number of green and
loggerhead turtles nesting annually in the Mediterranean. Oryx, 36(3): 227­236.
Caminas, J.A. 2004. Sea turtles of the Mediterranean Sea: population dynamics, sources of mor
tality and relative importance of fisheries impacts. FAO Fisheries Report 738: 27­84.
Camiñas, J.A., Valeiras, J. 2001. Marine turtles, mammals and sea birds captured incidentally
by the Spanish surface longline fisheries in the Mediterranean Sea. Rapp. Comm. Int. Mer
Medit., 36: 248.
Casale, P. 2005. Holes in the circle. A critical review of circle hooks as a measure for reducing
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Casale, P., Laurent L., De Metrio, G., 2004. Incidental capture of marine turtles by the Italian
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Casale, P., Freggi, D., Basso, R., Argano, R. 2005. Interaction of the static net fishery with log
gerhead sea turtles in the Mediterranean: insights from markrecapture data. Short note,
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Casale, P., Catturino, L., Freggi, D., Rocco, M., Argano, R. 2007. Incidental catch of marine tur
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1010­1018.

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Panou, A., Tselentis, L., Voutsinas, N., Mourelatus, Ch., Kaloupi, S., Voutsinas, V. Moschonas,
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Annex 11: WGECO request as part of the OSPAR QSR 2010
Introduction
With increasing public and political concerns on marine fisheries and environmental
issues, fisheries science and management has become increasingly complex. The
move to the ecosystem based approach to Fisheries Management has gained momen
tum as the multiple uses of marine resources have broadened to take account of eco
system considerations and the recommendations from the numerous international
agreements, conferences and summits held on the subject. Some of the most impor
tant of these include:
· The 1972 World Conference on Human Environment.
· The 1982 United Nations Law of the Sea Convention.
· The 1992 United Nations Conference on Environment and Development
and its Agenda 21.
· The 1992 Convention on Biological Diversity.
· The 1992 Habitats Directive
· The 1995 United Nations Fish Stocks Agreement.
· The 1995 FAO Code of Conduct for Responsible Fisheries.
· The 2001 Reykjavik Declaration.
· The 2002 World Summit on Sustainable Development.
· The 2002 Green Paper of the European Commission
· UN 2006 General Assembly to ensure protection of vulnerable marine eco
systems
· The 2007 Committee on Fisheries of the UN FAO on IUU and protecting
the marine environment
· The 2007 Integrated Maritime Policy for the European Union
ICES is in the process of restructuring its Science and Advisory processes and is col
laborating with HELCOM and OSPAR, among others, in the evolution of a holistic
ecosystembased approach to fisheries management. WGFTFB have been discussing
the subject of fishing impacts for a number of years and has addressed it as a specific
ToR in 2004 (ICES, 2004). Much of this though has been in isolation with limited dia
logue between other EG's including WGECO. WGFTFB has recognised this and has
discussed internally the need to define its new research direction, beyond the tradi
tional focus of bycatch reduction, into developing environmentally responsible fish
eries (ERF) in support of the ecosystem approach to fisheries management. The
stimulus for these discussions were prompted by the ever increasing international
calls for ban on bottom trawling on high seas' and also debate at the 2006 ICES Sym
posium on Fishing Technology in the 21st Century: Integrating Fishing and Ecosys
tem Conservation held in Boston (Glass et al., 2007). Since WGFTFB works closely
with and has industry people as part of their membership it felt that it should be
more proactive in the issue of ERF.
Recognizing this at last year's meeting in Dublin (ICES, 2007) an ad hoc group made
a first attempt to address this and explore ways of enhancing links with other ICES
WG's. WGFTFB also addressed a joint ToR with WGECO on the impacts of Crangon
beam trawl fisheries in the North Sea in 2007. Later in 2007 at the ICES ASC in Hel
sinki a ToR was formulated between the Chairs of WGFTFB and WGECO as follows:

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"For each OSPAR region, select and succinctly describe one or more representative
examples of gear modifications, which have resulted in changes to the ecosystem ef
fects of these gears, including if possible a range of ecosystem components."
The work contributes to WGECO ToR b) which will pull together an environmental
assessment of the impact of fisheries, in preparation for the OSPAR QSR. It is also
seen as means to begin the wider debate on how to properly assess the effect and im
pact of gear based measures through the development of a proper assessment
framework. This will be worked on at WGECO in 2009.
The representative case studies identified by WGFTFB to illustrate the positive and
negative impacts of different gear based technical measures are presented in Table
20­1 below.
Table 201. Case studies, identified for the description of representative examples of gear modifi
cations that are designed and selected for the mitigations of ecosystem effects.
Case study
Fishing gear
Target species
OSPAR-region
Ecosystem
component
1 (IRL)
Gill net
Mixed demersal
OSPARRegion II,
Marine mammals
III & IV
2 (Eng)
Demersal otter
Norway lobster
OSPARregion II
Fish species
trawl
(Nephrops
norvegicus)
3 (B, NL,
Flatfish beam
Mixed, demersal
OSPARregions II,
Fish species
UK)
trawl
fish species, mainly
III, IV
Benthic invertebrate
sole (Solea solea)
species
and plaice
(Pleuronectes
platessa)
4 (B, DK, F,
Shrimp beam
Brown shrimp
OSPARregion II
Mainly commercial
GER, NL,
trawl
(Crangon crangon.)
fish species
UK)
5 (Faroe
Pelagic otter
Blue whiting
OSPARregion I &
Fish species
islands)
trawl
(Micromesistius
V
poutassou)
The case studies are written in the following format.
i )
Brief overview of the situation prior to mitigation measures/regulation.
ii )
The drivers that initiated gear measures being developed or introduced.
iii ) A description of what was done in terms of mitigation measures.
iv ) A description of what management measures were taken after the re
search i.e. was the mitigation measure introduced into regulation or was
it only tested and then used or not used voluntarily
v )
A description of how the impacts of the gear modifications have been
assessed.
vi ) A description of how successful this has been in terms of reducing im
pacts.

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References
Glass, C. W., Walsh, S.J., Marlen, B., van, (Conveners). 2007. Fishing technology in the 21st cen
tury: integrating fishing and ecosystem conservation ICES Journal of Marine Science.
64(8):1499­1502.
ICES. 2007. Report of the ICESFAO Working Group on Fish Technology and Fish Behaviour
(WGFTFB), 23­27 April 2007, Dublin, Ireland. ICES CM 2007/FTC:06. 197 pp.
ICES. 2004. Report of the ICESFAO Working Group on Fish Technology and Fish Behaviour
(WGFTFB), 20­23 April 2004, Gdynia, Poland. ICES CM 2004/B: 05:Ref. ACE. 189 pp.
Case study 1 ­ introduction of Acoustic Deterrent Devices to reduce Ceta-
cean bycatch in Gillnet Fisheries
Brief overview of the situation prior to mitigation measures/regulation
The bycatch of marine mammals in European waters is not a new phenomenon, with
records of incidental cetacean mortality in driftnets dating back to the time of the
Roman Empire (Caddell, 2005).I more recent times, since the inception of the CFP
according to scientific advice, most fishing gears commonly used in European fisher
ies have been linked with some small cetacean (dolphin and porpoise) bycatch with
the most serious problems reported from static net fisheries. However, despite fears
within the scientific community over these large numbers of cetaceans being taken as
bycatch in European fisheries, any semblance of a coordinated policy to mitigate by
catch was only established with the adoption of the Habitats Directive in 1992. Al
though expressed in rather broad terms, Article 12.4 of the directive did establish a
clear mandate for Member States to address incidental catches of protected species
within areas under their jurisdiction but implementation has generally been insuffi
cient and uneven across Member States. Concerns at the level of cetacean bycatch,
therefore, have remained and highlighted by a number of EU funded studies, e.g. by
Sea Mammal Research Unit (SMRU) and Trengenza et al. (1997) which have demon
strated the scale of the problem in certain fisheries.
As a result of these continuing concerns, the European Commission asked ICES in
2001 to provide advice on the fisheries concerned, the risk posed by these fisheries to
identified populations and possible remedial action. It also asked the Scientific, Tech
nical, and Economic Committee on Fisheries (STECF) to review this advice and to
provide possible management advice. Following this review, in April 2004, EU legis
lation was adopted to promote bycatch mitigation, in the form of a regulation that
sought to address the specific issue of incidental cetacean mortality in Community
waters. This case study describes the introduction of this legislation and its subse
quent impact on cetacean bycatch rates.
Drivers that initiated gear measures being introduced
Although not exclusive to European Community fisheries by any means, the inciden
tal mortality of significant numbers of charismatic and photogenic marine mammals
and turtles has catalyzed the introduction of the measures to mitigate bycatch at
global, regional, and national levels. It is fair to say that the management goals in
most cases in introducing these measures were driven strongly by societal values
rather than scientific ones. Administrations have come came under increasing pres
sure from NGO's and the general public to act on this issue and ultimately forced
managers, including the EU to bring in legislation, even though there was an obvious
knowledge deficient in terms of actual level of bycatch in different fisheries and in
the development of suitable mitigation measures.

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It should be noted though that as identified by Werner et al. (2006), marine mammal
bycatch reduction is a very active area of research with numerous ongoing studies
and the frequent development and testing of novel initiatives and mitigation devices.
This research in many cases has been driven by genuine concerns among fisheries
managers, researchers and fishermen to protect endangered species, while some re
search has been motivated by the need to reduce gear damage caused by interactions
with marine megafauna or reducing predation of target catch by these species.
Mitigation measures or gear changes tested
In considering the issue of cetacean bycatch in gillnet fisheries, many researchers in
EU countries with perceived bycatch problems saw acoustic devices as a potential
solution. Such acoustic deterrents or `pingers' are small selfcontained battery oper
ated devices that emit regular or randomised acoustic signals, at a range of frequen
cies, and typically loud enough to alert or deter animals from the immediate vicinity
of fishing gear. Active pingers were first tested in Canada, primarily as a means to
reduce entrapment of baleen whales in coastal set nets and fish traps. These first de
vices, operated at 2.5 kHz, were subsequently tested on gillnets in the Bay of Fundy
and appeared to minimise harbour porpoise bycatch. Similar pingers were also de
ployed in the Makah salmon fishery off the Seattle coast and in Australia on beach
protection nets with reasonable results (SGFEN, 2001).
More complex devices were developed after experiments with gillnets in the Gulf of
Maine (Kraus et al., 1997). A design operating at 10 kHz was found to be effective at
reducing porpoise bycatch and ultimately formed the basis for legislation under
NFMS regulations. In the regulations the specifications for porpoise pingers were
defined as 300ms pulses of 10 kHz tonal pulses repeated at 4 second intervals with a
minimum source level of 132dB re 1 Pa.
A third generation pinger was developed in the late 1990s by Loughborough Univer
sity in the UK on the basis of tests with captive porpoises in Holland and Denmark.
These "PICE97" devices were trialled successfully in the Danish cod fishery during
the autumn of 1997, with a significant reduction in Harbour porpoise bycatch ob
served (Larsen, 1999). They differed from the original pingers in that they emitted a
variety of wide band frequency sweep type signals with randomised interpulse in
tervals, rather than simple single tonal pulses.
Further research with these devices followed in the UK (Goodson et al., 2001), Medi
terranean (Imbert et al., 2002) and in the US (Barlow and Cameron, 1999) and at least
two devices the Aquamark and Dukane pingers had been shown to reduce bycatch.
In the STECF report of 2002 it was concluded:
"There was general agreement that devices considered suitable for use should have proven
aversive abilities within the fishery and for the species giving concern. Two of the currently
available devices (AQUAmark, Dukane) fitted this definition for bottomset gill nets and por
poises and therefore could be regarded as suitable standards that any further pinger should
equal or exceed in these circumstances. It was noted field trials to demonstrate operational
effectiveness were needed in addition to evidence of aversion by the species of concern to the
specific acoustic signal of any new device".
STECF also recommended that within an overall management framework there must
be a monitoring and surveillance programme to identify fishery métiers, or times and
areas, where cetacean bycatch is a problem, and to provide quantitative estimates of
the levels of bycatch for each species/'stock'. Timely population assessments are also
required within this framework. There must be a recognised means of determining

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unacceptable bycatch levels, and an institutional framework for devising bycatch re
duction plans where these are necessary. Beyond this, there needs to be a means of
implementing any bycatch reduction plan, including methods of enforcement, and of
continued monitoring and feedback to ensure the overall objectives are met. The sub
group concluded with a series of recommendations, headed by the recommendation
that a by catch management framework should be established at an EU level at the
earliest opportunity.
Management measures introduced after initial research
In 2004 the EU took a decision to better protect cetaceans in EU waters, following
much of the advice received from ICES and STECF. The measures introduced in
Regulation 812/2004 included a step by step reduction of the use of driftnets from 1
January 2005 until complete prohibition by 1 January 2008, the monitoring of by
catches through observer schemes and the compulsory use of acoustic deterrent de
vices on fishing nets.
The use of acoustic devices or pingers, was made mandatory for gillnet fisheries
(from June 2005 for the North Sea and the Baltic Sea, from January 2006 in the Celtic
Sea and the western Channel and 2007 in the eastern Channel) for all vessels over
12m. The regulation provided technical specifications for the efficiency of the acoustic
deterrent devices, while there was also a requirement for scientific studies or pilot
projects to increase knowledge about the effects over time of the use of acoustic de
terrent devices. Member States were encouraged to test newly developed and effi
cient types of acoustic deterrent devices not in conformity with the technical
specifications laid down in this Regulation on a temporary basis.
Impact Assessment of the gear modifications
The measures introduced were to be closely monitored in order to allow for their ad
aptation over time, while Member States were tasked with ensuring full monitoring
of the state of cetacean populations as required under the Habitats Directive. Subse
quently, though, the introduction of acoustic deterrent devices under Regulation
812/2004 has been compromised due to a combination of factors. In most EU coun
tries anecdotal evidence suggests there is only limited enforcement of the regulations
and only a limited number of vessels complying with the regulations; e.g. Denmark
reports around 30 vessels, while Sweden report 9 vessels in the Baltic Area using
pingers. In both of these Member States pilot projects funded under FIFG have been
used as a mechanism to supply pingers to vessels. Such pilot projects or grant aid
schemes to offset costs for introduction have some merit but are not the complete so
lution and probably result in initial uptake by fishermen but as such schemes usually
only apply to first purchase, subsequent maintenance or replacement is at best spo
radic
In addition, adequately quantifying bycatch of protected species and the impact of
introducing mitigation technologies requires essentially a high level of on board ob
server coverage (typically at a level of 25­30% of total fishing effort) to be able to pro
vide accurate estimates and associated confidence limits around estimates
(Northridge and Thomas, 2003). Levels of coverage by nation and fishery on intro
duction of mitigation technologies are frequently at much lower levels than this.
Regulation 812/2004 seeks assessment and monitoring of the impact of pingers on
bycatch but in reality very few Member States have been able to carry out such moni
toring. This is mainly due to the costs involved in maintaining observer programmes.
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plement the quantitative data gathered from observer programmes. This lack of sys
tematic monitoring has prevented the true extent and potential impacts of pingers on
protected species bycatch from being fully understood or documented in EU waters.
Scientific monitoring is essential to identify unexpected negative effects of mitigation
devices.
It is also worth noting that fishermen in a number of European countries have raised
concerns about the resilience of the current commercially available "pingers" and
also the practicalities of using these devices for commercial fisheries. These concerns
have been addressed in a series of trials carried out in Ireland, UK, Sweden, Denmark
and France in 2005 and 2006 (Cosgrove et al., 2005). As a result of this work, all avail
able models of pinger have now been extensively assessed in terms of ease of use,
resistance to damage and longterm running costs. The trials have highlighted a
number of serious issues and difficulties relating mainly to the reliability of the de
vices. Problems with deployment were found, although some of these problems have
been resolved by changes to rigging or operating practice. It is clear that more con
sideration of the construction, practical handling and deployment of such devices is
required before they can be considered a universal solution to certain bycatch prob
lems in gillnet fisheries. Costs associated with the introduction of mitigation tech
nologies remain an issue for fishermen and ways to help mitigate economic costs
should be carefully considered. For instance the requirement for fishermen to use
pingers under Regulation 812/2004 has very real cost implications for fishermen. In
Europe current commercially available devices cost in the region of 50­100 per de
vice and a vessel fishing with 10km of gillnet gear using the recommended spacing
between devices of 100m200m would require 50­100 devices at a cost in the region
of 2,500­5,000. Given there are still technical difficulties with these devices, which
were flagged when 812/2004 was being formulated, these costs are significant and
have undoubtedly been a hindrance to acceptance by fishermen in Europe.
In adopting measures it is important to define which species the mitigation devices
are designed to protect. Once again in this respect Regulation 812/2004 is perhaps
flawed given the objective of the regulation is to mitigate incidental catches of ceta
cean species in general. Research and development, however, has mainly been fo
cused on the use of pingers to reduce harbour porpoise bycatch in gillnet fisheries
and the results of trials involving other cetacean species are less clearcut, with
somewhat contradicting results (Barlow and Cameron, 2003; Anon., 2006). It is likely
that the use of pingers in their present form as required in Regulation 812, even with
100% compliance would lead to a reduction in bycatch of species such as common or
bottlenose dolphins.
At the currently there are five recognised manufacturers of commercial pingers, al
though other "cruder" devices exist. Two of these devices are made in the US, one in
the UK, one in Italy and one in the Netherlands. While their signal characteristics are
well suited for Harbour porpoises, only limited success has been achieved with other
cetacean species. For species such as bottlenose dolphins, tests have shown them to
be wholly ineffective (Anon., 2006).
Conclusion
In conclusion it is clear that the successful implementation of a framework for by
catch reduction can be encouraged by appropriate legislation, while conversely legis
lation can also unwittingly be an impediment to successful introduction of bycatch
mitigation technologies (ICES, 2008). Framing legislation therefore needs to be done
after consideration of all of the issues raised above. In this sense 812/2004 has largely

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failed in introducing the use of pingers into the identified problem fisheries by being
unrealistically prescriptive and not taking account of all of the technical, biological
and economic issues fully. In this case there has perhaps been a failure by managers
to consider all of the issues and impacts of adopting legislation to use bycatch reduc
tion devices leading to:
· Poor compliance by fishermen with the regulations;
· Negative Ecological Impacts;
· Economic Impacts on stakeholders;
· Technical Problems with the devices;
· Biological Impacts;
· Poor monitoring; and
· Poor acceptance by stakeholders.
References
Anon. 2006. Nephrops and Cetacean species selection information and technology. EU Project
NECESSITY. 501605. Interim Report (restricted).
Barlow, J., and Cameron, G.A. 2003. Field experiments show that acoustic pingers reduce ma
rine mammal bycatch in the California drift gillnet fishery. Presented to the Scientific
Committee of the International Whaling Commission, Grenada, 1999.
Barlow, J., and G. A. Cameron. 1999. Field Experiments Show that Acoustic Pingers Reduce
Marine Mammal Bycatch in the California Drift Gillnet Fishery. Presented to the Scientific
Committee of the International Whaling Commission, Grenada, 1999.
Caddell, R. 2005. Bycatch mitigation and the protection of cetaceans: recent developments in
EC law. Journal of International Wildlife Law & Policy.
Cosgrove, R., Browne, D., and Robson, S. 2005. Assessment of Acoustic Deterrent Devices in
Irish Gill Net and Tangle Net Fisheries. BIM Report, 05MT07. 30pp.
Goodson, A.D., Datta, S., Di Natale, A., Dremiere, PY. 2001. Project ADEPTs AcousticDeter
rents to Eliminate Predation on Trammels. Final Report to the European Commission DX
XIV 898/019, p110+Appendices and a CDDatabase.
ICES. 2008. Report of the Study Group for Bycatch of Protected Species (SGBYC), 29­31 Janu
ary 2008, ICES, Copenhagen, Denmark. ICES CM 2008/ACOM:48. 82 pp.
Imbert, G., J.C. Gaertner, S. Cerbonne, and L. Laubier. 2002. Effet des repusifs acoustiques sur
la capture de dauphins dans les thonailles. Report to the Direction de lAgriculture et des
Ressources Naturelles. Universite de la Mediterranee Centre DOceanologie de Marseille,
Marseille.
Kraus, S.D., Read, A.J., Solow, A., Baldwin, K., Spradlin, T., Anderson, E., Williamson, J. 1997.
Acoustic alarms reduce porpoise mortality. Nature, 388: 525­526.
Larsen, F. 1999. The effect of acoustic alarms on the bycatch of harbour porpoises in the Danish
North Sea set gill net fishery: a preliminary analysis. Paper SC/51/SM41 submitted to the
51st IWC meeting, Grenada.
Northridge, S.P., and Thomas, L. 2003. Monitoring levels required in European fisheries to
assess cetacean bycatch, with particular reference to the UK fisheries. Final Report to DE
FRA (EWD). 37pp.
SGFEN (Subgroup on Fishery and Environment). 2002. Incidental catches of small cetaceans.
Report of the second meeting of the subgroup on fishery and environment (SGFEN) of the
scientific, technical, and economic committee for fisheries (STECF), Brussels, 11­14 June
2002. Commission Staff Working Paper, Commission of the European Communities.
SEC(2002) 1134.63pp.

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SGFEN (Subgroup on Fishery and Environment). 2001. Incidental catches of small cetaceans.
Report of the first meeting of the subgroup on fishery and environment (SGFEN) of the
scientific, technical, and economic committee for fisheries (STECF), Brussels, 10­14 De
cember 2001. Commission Staff Working Paper, Commission of the European Communi
ties. SEC(2002) 376.83pp.
Tregenza, N. J. C., Berrow, S. D. et al. 1997. Harbour porpoise (Phocoena phocoena L.) bycatch in
set gillnets in the Celtic Sea. ICES Journal of Marine Science, 54(5): 896­904.
Werner, T., Kraus, S., Read, A., and Zollet, E. 2006. Fishing techniques to reduce the bycatch of
threatened marine animals. Marine Technology Society Journal, Volume 40, 3: 50­68.
Case study 2 ­ Farne Deep Nephrops fishery, England
Brief overview of the situation prior to mitigation measures/regulation
The EU Nephrops norvegicus fishery in the North Sea is currently managed by three
regulatory mechanisms: output (for some species) is restricted by TACs; input is con
trolled by limiting daysatsea; and exploitation patterns are modified by technical
conservation measures specifying gear restrictions and Minimum Landing Sizes. An
important Nephrops trawl fishery in the North Sea lies adjacent to the Farne Deep, off
the east coast of England. In the 2001/2002 season, up to 82 vessels worked on this
fishery; the fleet consisted of vessels less than 30m long. The vessels use single and
twin Nephrops otter trawls. Nets with a small mesh size are legally allowed to catch
Nephrops norvegicus, compared to other demersal whitefish species and consequently
large quantities of other organisms can also be caught, and much of this is discarded
dead. Since 2002 the fleet number has fluctuated but a significant fleet still prosecutes
this fishery.
Drivers that initiated gear measures being introduced
The amount of material caught and subsequently discarded in the English Nephrops
fishery was estimated at 4890 tonnes in the 2001/2002 season equating to a discard
rate of 57%. Discards in this fishery are dominated by whiting; other significant com
ponents of the discards include haddock, Nephrops and commercial flatfish species. It
has been estimated that whiting discards from this fishery account for 16% of the es
timated whiting discards for the entire North Sea. The weight of discarded whiting
was estimated at six times that of the landed weight.
Scientists considered that the high discard mortality on small commercial fish was
destructive and had contributed to the decline of the important North Sea stocks and
consequent reduction in yields. Moreover, changes in community structure through
discarding, either directly through discard mortality or indirectly, modify the energy
flow through foodwebs with the potential to alter ecosystem dynamics. Therefore,
the economic and ecological consequences of discarding are intrinsically linked and
not confined to the direct mortality of commercial species. Despite the absence of
predictable outcomes for the reduction in discards of all species, reducing discards of
all species meets the requirements of the precautionary principle and ecosystem
based approach as defined in EU legislation, the Bergen Declaration and OSPAR bio
diversity action plans.
Mitigation measures or gear changes tested
Considerable research into fishing gearbased measures to improve selectivity has
been undertaken. The potential for structural changes in trawls to facilitate the re
lease of unwanted fish was recognized as early as the 1980s and is the method of dis
card reduction most supported by North Shields fishers. The different behaviours

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exhibited by the main discarded species in Nephrops trawl fisheries can be exploited
to improve the selectivity of trawls. Whiting and haddock rise when inside the trawl,
while Nephrops and cod remain near the bottom. Separating cod, and other ground
fish, from Nephrops remains the most challenging task for gear technologists in this
fishery. However, a recent review concluded that there is currently adequate techni
cal ability to significantly improve the selectivity of Nephrops trawls.
If the aim of fishery managers is to retain as much of the marketable fish as possible
but to reduce discards, then designs involving Square Mesh Panels, constructed of
large mesh, highstrength thin twine, possibly in combination with guiding pan
els/funnels/ropes should be further developed. If, however, the aim of managers is to
minimise all fish catch or the catch of a particular overexploited species, such as cod,
then a move towards a singlespecies fishery is more appropriate. A selection grid
system, or prawn trawls historically used, with low openings and reduced top sheet
lengths offer promising solutions in this instance.
The relative difference of the effect on North Sea fish stocks of introducing five trawl
designs developed by gear technologists has been modelled. The designs included
using a squaremesh panel constructed of high strength and low diameter material, a
selection grid in combination with a squaremesh codend, using two square mesh
panels, a cutaway trawl (with a setback headline) and a 100mm codend. All the de
signs indicated that they would have a positive effect on the North Sea whiting stock.
However, only through the implementation of a trawl with a grid combined with a
squaremesh codend was there likely to be any positive effect on haddock and cod
stocks. This is because this was the only design that reduced the catches of fish of all
sizes and not just the juveniles and also because this fishery caught few haddock and
cod relative to other fisheries in the North Sea.
Management measures introduced after initial research
Some of the selective designs developed have been implemented. The insertion of a
squaremesh panel into the topsheet of singlerigged trawls has been mandatory
since 1991/92 and an additional 140mm diamond mesh panel inserted behind the
headline since January 2002. Furthermore, prior to 2002 the minimum legal codend
mesh size was 70mm for singlerigged trawls, but since January 2002, this has been
increased to 80mm. The threat of severe restrictions to fishing opportunities or clo
sure of the English Nephrops fishery in 2002 in conjunction with the new regulations
imposed on other fisheries provided the incentive to implement these gear changes.
Impact Assessment of the gear modifications
There has also been some evaluation of the effectiveness of these regulations. The
composition of catches was monitored just before and after these regulatory changes.
The trawl modifications demonstrated a reduction in discard rate for whiting of 11%.
A second more recent study, utilising observer data to compare a longer period be
fore and after the introduction of these changes has also shown that whiting selectiv
ity has improved. The threat of severe fishing restrictions was originally due to the
poor status of the cod stock, however the regulations introduced were more likely to
reduce the capture of small haddock and whiting rather than benefit cod. Therefore,
although the regulations successfully reduced whiting discards it is not clear whether
the objectives of the managers were met. The new regulations introduced in the Farne
Deep fishery did, however, allow the fishery to continue without further restrictions
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As part of the 2007 EUNorway negotiations, it was agreed that the selectivity of
whiting in vessels using trawls with an 80­99mm mesh net in the North Sea would be
improved. This sector includes the vessels of this Nephrops fishery; a reduction of 40%
in whiting discards was agreed. In 2008, trials of a double squaremesh panel, con
structed of high strength low diameter twine will be undertaken onboard trawlers in
this fishery. Based on previous trials this will meet the required objectives. The
mechanism by which regulations have been implemented in this fishery illustrates
that there is adequate technical ability to significantly improve the selectivity of
Nephrops trawls but fishers are not taking up the developments until the sufficient
level of incentive is generated.
Conclusions
It is apparent that technical measures in this case i.e. the gear modifications high
lighted do provide a partial solution to discarding problems in North Sea Nephrops
fisheries. All are technically feasible and workable, with some shown to provide
much improved selectivity but with corresponding losses of marketable fish which
have been a stumbling block for their voluntary adoption by fishermen. In the ab
sence of appropriate incentives in terms of increased quota allocation or market posi
tion it is unlikely that this will change much in the near future without a change in
focus in management..
References
Catchpole, T.L., Revill, A.S. 2008. Gear technology in Nephrops trawl fisheries. Reviews in Fish
Biology and Fisheries, 18, 17­31.
Catchpole, T.L., Tidd, A.N., Kell, L.T., Revill, A.S., Dunlin, G. 2007. The potential for new
Nephrops trawl designs t positively effect North Sea stocks of cod, haddock and whiting.
Fisheries Research, 86, 262­267.
Catchpole, T.L., Revill, A.S., Dunlin, G. 2006. An assessment of the Swedish grid and square
mesh codend in the English (Farne Deeps) Nephrops fishery. Fisheries Research, 81, 118­
125.
Catchpole, T.L., Frid, C.L.J., Gray, T.S. 2006. Resolving the discard problem A case study of
the English Nephrops fishery. Marine Policy 30, 821­831.
Catchpole, T.L., Frid, C.L.J., Gray, T.S. 2006. Importance of discards from the English Nephrops
norvegicus fishery in the North Sea to marine scavengers. Marine Ecology Progress Series,
313, 215­226.
Catchpole, T.L., Frid, C.L.J., Gray, T.S. 2005. Discarding in the English northeast Nephrops
norvegicus fishery: the role of social and environmental factors. Fisheries Research 72, 45­
54.
Enever, R., Revill, A. S., Grant, A. Discarding in the North Sea and on the historical efficacy of
gearbased technical measures in reducing discards. Cefas, Unpubl.
Revill, A.S., Dunlin, G., Holst, R. 2006. Selective properties of the cutaway trawl and several
other commercial trawls used in the Farne Deeps North Sea Nephrops fishery. Fisheries
research, 81, 268­275.
Revill, A.S., Catchpole, T.L., Dunlin, G. 2007. Recent work to improve the efficacy of square
mesh panels used in a North Sea Nephrops norvegicus directed fishery. Fisheries Re
search, 85, 335­341.

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Case study 3 ­ Flatfish beam trawl fisheries, Belgium, the Netherlands, UK
Brief overview of the situation prior to mitigation measures/regulation
Belgium, the Netherlands and the United Kingdom (UK) are the main nations with
beam trawl fisheries. These fleets target species such as flatfish, mainly sole (Solea
solea) and plaice (Pleuronectes platessa), and round fish species as cod (Gadus morhua).
The fishing grounds are the greater North Sea, the Celtic Sea, Irish Sea and the Bay of
Biscay (OSPARregions II, III and IV) in ICESSubareas IVa, b, c, VIIa, d, e, g, h and
VIIIa. The activities of these fleets have been well studied and the effort patterns, as
well as the impacts are probably as well documented as any fleet in the EU.
Drivers that initiated gear measures being introduced
The most important direct ecosystem effects of beam trawl fisheries are on habitats,
benthos, commercial fish species and wider fish communities (ICES, 2006). This case
study focuses on the technical alterations to beam trawls that can reduce the direct
ecosystem effects of this fishing method. The need for selective beam trawls is recog
nised at many levels. A midterm review of the Common Fisheries Policy (Anon.,
1991) at that time stressed the importance of reducing fish discards and the need for
more research and acceptance of selective gears by fishermen. Later on, in 2002, the
green paper of the European Commission on the Common Fisheries Policy
(http://europa.eu.int/comm/fisheries/greenpaper/green1_nl.htm) stated that there was
a need to further develop an ecosystemoriented approach to all areas of fishery
management, including fishing gear technology. This implied that gear technology
research should not only focus on the effects of beam trawl fisheries on commercial
fish species, but also on other ecosystem effects. As beam trawl fisheries also have a
considerable impact on the biomass, production and diversity of benthic communi
ties (e.g. Lindeboom and de Groot, 1998; Løkkeborg, 2005; Hiddink et al., 2006, Kaiser
et al., 2006; Queirós et al., 2006), research has investigated ways to overcome these
problems.
Mitigation measures or gear changes tested
There have been numerous projects on ways to improve fish selectivity in flatfish
beam trawls. In the SOBETRA project (Optimization of a species selective beam
trawl) (Fonteyne et al., 1997; van Marlen, 2003) a number of gear modifications were
tested, aimed at the reduction of demersal fish discards in the flatfish beam trawl
fisheries. The gear modifications tested aimed to create large escape zones for round
fish in the top panel of the beam trawl without affecting the catch of flatfish. Two
types of escape openings were tested for Rnets (beam trawlers using chain matrix),
namely square mesh top panels and cutaway covers (reduced top sheets), and
whereas large mesh top panels have been tested for Vnets (beam trawlers using tick
ler chains). Several representative categories of vessels were chosen to test the new
designs extensively under commercial conditions through the catch comparison
methodology. In general it was found that the species selectivity of the beam trawls
could be improved for whiting and haddock, but much less for cod. This is in accor
dance with underwater observations showing that round fish species stay in different
levels in a trawl with haddock in the upper level, whiting in the middle and cod in
the lower level (Main and Sangster, 1982). Hence, the fish closest to the escape zone
in the upper level have more chance to swim out of the trawl before entering the
codend. These modifications were proven to work although the degree of success
depended on the vessel size and gear size due to the fact that on smaller vessels using
smaller nets the escape opening cannot be made sufficiently large to allow adequate

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escape of round fish without incurring losses of flatfish. Therefore the conclusion
from this work was that the results did not necessarily justify the use of these species
selective devices across all beam trawl vessels.
Mitigating the effects of flatfish beam trawls on benthic invertebrates has been inves
tigated in the EUproject "REDUCE" (Anon., 2002; Fonteyne and Polet, 2002; van
Marlen et al., 2005), several national projects (the UK national FIFG funded project
FGE 158, the Belgian EFF funded project "IDEV") and is currently under investiga
tion in the EUproject "DEGREE". Beam trawls cause direct mortality to benthos in
two ways (Revill and Jennings, 2005). First, the shoes, tickler chains or chain mat hit
animals on the seabed (Bergman and van Santbrink, 2000). Second, animals are
caught in the net and die from injuries sustained in the net, during hauling or when
the catch is processed and/or discarded (Lindeboom and de Groot, 1998). The most
effective way to reduce the environmental impact of beam trawling is to control the
mortality caused by shoes, tickler chains or chain mats hitting animals on the seabed
(Bergman and van Santbrink 2000). While removing the ground gear and using other
approaches such as wheels, water jets, dropper chains, brushes, etc, to drive target
species out of the substratum can achieve this; commercially acceptable methods
have yet to be fully developed (Anon., 2002; Revill and Jennings, 2005). Again losses
of target species have been a problem. The use of electric pulses as alternative stimu
lus is currently under investigations in the Netherlands (van Marlen et al., 2006) and
again this has shown to be technically feasible although there are concerns from fish
ermen on catch levels of sole, while there are concerns from ecologists of the impacts
on fish that encounter the electrical stimuli but are not subsequently caught. (ICES,
2005).
Bycatch mortality of benthic organisms accounts for 5­10% of the total benthic mor
tality caused by beam trawling. Commercially acceptable technical modifications
have been developed for this kind of mortality. The benthos release panel seems to be
a simple and practical solution to release bycaught benthic invertebrates from a flat
fish beam trawl without substantial loss of commercial fish species (Fonteyne and
Polet, 2002; Revill and Jennings, 2005; van Marlen et al., 2005). The mesh size used
needs to be balanced against the reduction in benthos catch and the loss of commer
cial fish species through the panel that can be experienced. Based on the research
work carried out with this gear modification, a mesh size of 150 mm seems to be the
best compromise.
Management measures introduced after initial research
In the framework of the Council Regulation laying down certain technical measures
for the conservation of fisheries resources (850/98), a general increase in mesh size
and the use of square mesh panels in towed gears was suggested to improve the se
lectivity of towed fishing gears. On 19 October 2001, EU Regulation 2056/2001 was
adopted, establishing additional technical measures for the recovery of the stocks of
cod in the North Sea and to the West of Scotland. It included a provision for the
minimum codend mesh size of beam trawls in the North Sea must be 80 mm South of
56° N, and 120 mm North of 56 °N (with a restricted area in the western part of the
central North Sea, where codends of 100 mm mesh size were made compulsory).
However, a general increase in mesh size as first suggested in earlier drafts of the
regulations was firmly rejected due to perceived losses of sole catches. These regula
tions also included the mandatory insertion of a panel of no less than 180mm in the
top panel of all beam trawls.

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It is interesting to note that in the SOBETRAproject, Fonteyne et al. (1997) advised on
the basis of the results with square mesh top panels, cutaway cover sheets or a large
mesh cover sheets that these modifications be included in future regulations. The
mesh size used in beam trawls at that time, was 120mm, occasionally 150mm if sole
were not the target species (Lindeboom and de Groot, 1998). The findings of SOBE
TRA were partially taken on board in Regulation 2056/2001 with the provisions for
the use of the 180mm panel but these mesh sizes were a lot smaller than the ones
suggested by Fonteyne et al. (1997) and did not differ according to vessel size con
trary to the findings of the SOBETRA project that clearly demonstrated big differ
ences in catches with such panels depending on vessel size. Effectively the regulation
took account of the findings of research work but did not necessarily implement it as
recommended.
On a more positive note there a number of other discard (fish and benthos) reduction
devices such as benthic release panels that are not currently included in technical
measures legislation, however, there is evidence of increasing voluntary use of some
of them. The Belgian and Dutch fishermen's organisation each have setup national
Working Group specifically examining technical modifications to beam trawls for
discard reduction. Included within this Working Group is a commitment that the
modifications agreed by fishermen's will be scientifically tested by the research insti
tutes IMARES (NL) and/or ILVO (B). The UK beam trawl fisheries sector is taking
similar initiatives through the Fisheries Science Partnership, building relationships
between scientists from CEFAS (UK) and fishermen (Revill et al., 2007).
The use of more selective beam trawl gear is also being driven by the market place as
well. Public perception of beam trawl caught fish has become increasingly negative
putting pressure on fishermen to adopt more responsible fishing practices. This move
has gained increasing momentum worldwide with the advent of certification
schemes such as MSc and also through competitions such as the WWF Smart Gear
competition or the Responsible Fishing Gear competition in the UK. The effectiveness
of the modifications is in this way better supported by the fishing industry and is bet
ter adapted to different fishing grounds (A. Revill, pers. comm.).
Impact Assessment of the gear modifications
The effect of the existing regulations under 850/98 and the additional requirements
included in 2056/2001 designed to improve species selectivity have not been properly
evaluated. Enever et al. (submitted) has showed a significant reduction in fish dis
cards by number by increasing mesh sizes from 80­89mm to 90­110mm and 110­
120mm (Figure 20­1) but other than the original SOBETRA project there has been no
assessment of the effect on stocks of using the 180mm panel.

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Figure 20­1. Proportion of catch discarded (all finfish numbers combined) by English and Welsh
registered beam trawlers (b) in the North Sea between 1999 and 2006 fitted for varying codend
mesh size groups (Modified from Enever et al., submitted).
Regarding the other devices tested again only limited assessment has been carried
out. Some survival studies have been completed with Benthic Release panels and im
pact studies of the electric beam trawl are ongoing.
Conclusions
The introduction of gear based technical measures into the beam trawl fleets to im
prove selectivity and reduce impact on benthic organisms largely mirrors the previ
ous case study in the Nephrops fisheries. The gear measures developed are all
technically feasible but have not necessarily been translated into legislation. In the
case of the large mesh top sheet or square mesh panels tested the recommendations
from testing have not necessarily been correctly interpreted into regulations. The
voluntary uptake of the benthos release panel in particular is more encouraging and
seems to be growing. The motivation for this is largely market driven.
Assessment of the impacts of the measures has proven difficult and therefore largely
is a work in progress. Scientific followup will be difficult without fishermen's coop
eration, a high input from them will be needed for any assessment. The study by En
ever et al. (submitted) though has shown technical management measures for the
protection of fish species can work. Other technical measures are still under investi
gation, e.g. electrified beam trawling, T90 and square mesh codends but indications
are that a combination of modifications, focusing on the reduction of discards, has
potential (Depestele et al., 2008), especially for fish species and to a lesser extent for
invertebrate species. Their effect on the reduction of shortterm direct mortality has
been estimated during sea trials in the developmental stage. The potential effects on
fish and/or benthic invertebrate populations on the other hand has up till now not
been modelled prior to implementation, nor assessed after implementation. Attempts
for estimating the efficacy of technical modifications on the fleet level are currently
undertaken in the EUproject "DEGREE".
References
Anon. 1991. The Common Fisheries Policy midterm review. Proceedings of the Conference
held in Cork, Ireland on 10th and 11th May 1991, 54pp.

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Anon. 2002. Reduction of Adverse Environmental Impact of Demersal Trawls (REDUCE). Final
Report of EUcontract FAIR CT97­3809. National University of Ireland, Ireland. 257pp.
Bergman, M.J.N., van Santbrink, J.W. 2000. Mortality in megafaunal benthic populations
caused by trawl fisheries on the Dutch continental shelf in the North Sea in 1994. ICES J.
mar. Sci., 57: 1321­1331.
Depestele, J., Polet, H., Van Craeynest, K., and Vandendriessche, S., 2008. A compilation of
length and species selectivity improving alterations to beam trawls. Project report. Project
no. VIS/07/B/04/DIV. Study carried out with the Financial support of the Flemisch Com
munity, the European Commission (FIOV) and Stichting Duurzame Visserijontwikkeling
vzw. Promotor: Stichting Duurzame Visserijontwikkeling vzw. 56p.
Enever, R., Revill, A. S., and Grant, A. Submitted. Discarding in the North Sea and on the his
torical efficacy of gearbased technical measures in reducing discards. Fish. Res.
Fonteyne, R. 1997. Optimization of a species selective beam trawl (SOBETRA). Final Project
Report EUProject AIR2CT93­1015.
Fonteyne, R., and Polet, H. 2002. Reducing the benthos bycatch in flatfish beam trawling by
means of technical modifications. Fish. Res. 55, 219­230.
Hiddink, J.G., Jennings, S., Kaiser, M.J., Queir, A.M., Duplisea, D.E., Piet, G.J. 2006. Cumulative
impacts of seabed trawl disturbance on benthic biomass, production, and species richness
in different habitats. Canadian Journal of Fisheries and Aquatic Sciences, 63: 721­736.
ICES. 2006. Report of the Working Group on Ecosystem Effects of Fishing Activities (WGECO),
5 12 April 2006, ICES Headquarters, Copenhagen. ACE:05. 174 pp.
Kaiser, M.J., Clarke, K.R., Hinz, H., Austen, M.C.V., Somerfield, P.J., and Karakakkis, I. 2006.
Global analysis of response and recovery of benthic biota to fishing. Mar. Ecol. Progr. Ser.,
311: 1­14.
Lindeboom, H.J., and de Groot, S.J. 1998. ImpactII: The effects of different types of fisheries on
the North Sea and Irish Sea benthic ecosystems. NIOZrapport, 1998(1). Netherlands Insti
tute for Sea Research: Den Burg, Texel (The Netherlands). 404 pp.
Løkkeborg, S. 2005. Impacts of trawling and scallop dredging on benthic habitats and commu
nities. FAO Fisheries Technical Paper. No. 472. Rome, FAO. 2005. 58 pp.
Main, J., and Sangster, G.I. 1982. A study of a multilevel bottom trawl for species separation
using direct observation techniques. Scottish Fisheries Research Report No. 26, 17 pp.
Marlen, B. van, 2003. Improving the selectivity of beam trawls in The Netherlands: the effect of
large mesh top panels on the catch rates of sole, plaice, cod and whiting Fisheries Research
63 (2). p. 155 ­ 168.
Marlen, B. Van, Bergman, M.J.N., Groenewold, S., Fonds, M. 2005. New approaches to the re
duction of nontarget mortality in beam trawling. Fisheries Research 72 (2­3): 333­345.
Marlen, B. Van, Grift, R.E.; Keeken, O.A. van, Ybema, M.S., Hal, R. van, 2006. Performance of
pulse trawling compared to conventional beam trawling. IJmuiden: IMARES, (Report
C014/06) p. 60.
Queirós, A.M., Hiddink, J.G., Kaiser, M.J., Hinz, H. 2006. Effects of chronic bottom trawling
disturbance on benthic biomass, production and size spectra in different habitats. J. Exp.
Mar. Biol. Ecol., 335, 91­103.
Revill, A.S., Jennings, S.J., 2005. The capacity of benthos release panels to reduce the impacts of
beam trawls on benthic communities. Fish. Res. 75, 73­85.

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Case study 4 ­ shrimp beam trawl fisheries, Belgium, Denmark, France,
Germany, the Netherlands, UK
Brief overview of the situation prior to mitigation measures/regulation and drivers
that initiated gear measures being introduced
The shrimp beam trawl fisheries in the North Sea and a summary of the state of
knowledge concerning its impact upon benthic habitats and the wider marine ecosys
tem has been described by WGECO in 2007 (ICES, 2007b) and acknowledged by
WGFTFB in 2007 (ICES, 2007a). WGCRAN, in responding to the WGECO report of
2007, perceived some of the findings of the WGECO report to be incorrect or give a
misleading picture of the C. crangon fisheries (ICES, 2007c). WGECO concluded that
the removal of the target species (C. crangon) and the unwanted bycatch of juvenile
commercial fish to be major concerns in these fisheries. WGCRAN concluded that the
former one is not considered as a primary concern as the removal of C. crangon is
necessary for the fishery to be viable and an unavoidable consequence of the fishery
(ICES, 2007a). Moreover, Crangon stocks do not show signs of overexploitation (ICES,
2007a; ICES 2007c; Suuronen and Sarda, 2007). The latter concern of fish bycatch has
largely been addressed by gear research.
Mitigation measures or gear changes tested, management measures introduced after
initial research and impact assessment of the gear modifications
Revill et al. (1999), Revill (2001) and Polet (2003) assessed the likely outcomes of the
use of selective trawls in the Crangon fisheries in terms of the benefits to fish stocks
and their future landings. This research triggered the current technical measures
(sieve nets and rigid grids) introduced into legislation in 2003 for the C. crangon fish
eries (ICES, 2007a). This technical management measure has been assessed in a study
of the UK fishery (Catchpole et al., 2008). ICES (2007a) and this study legitimately as
sumed, given the similarity between fisheries that these findings can be applied to the
North Sea C. Crangon fishery and concluded that sieve nets appear to function as in
tended in reducing bycatch of unwanted fish species but derogations applying to the
main EU brown shrimp fleets of Germany and The Netherlands, which state that no
selection device is required for up to half of the year do compound the situation.
Overall, the legislation reduces the undesirable capture of unwanted marine organ
isms and, as such, is consistent with the requirements of the precautionary principle
and ecosystemapproach as defined in EU legislation. It is particularly effective at
reducing bycatch levels of cod and relatively larger fish of all species (>10 cm in
length), but less so at reducing 0 group plaice, which make up the largest component
of the bycatch. The legislation has had a positive effect, and it represents the best
available solution, but it does not sufficiently address the bycatch issue in the Crangon
fishery.
WGFTFB in its review of the fisheries concluded that the existing technical measures
used in these fisheries are the most effective gearmodifications available at present
for reducing bycatch. However, the ICESFAO WGFTFB also recommended that
these existing technical measures are only partially effective, and that there is a clear
need to develop further measures to reduce discarding in these fisheries beyond ex
isting levels (i.e. new gears, spatial / temporal measures etc). These findings are con
firmed by Suuronen and Sarda (2008).
WGFTFB recommended:
· That technical development with onboard catch processing and deck sort
ing equipment (i.e. rotary riddles with constant running water) may fur

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ther improve discard survival rates, but that scientific followup studies
are required to confirm this.
· Their should be support for the research and development of new meas
ures which could be used to effectively harvest C. crangon while reducing
discards of unwanted species beyond current levels.
· That the electricshrimp beam trawl may be one such technical measure,
but as yet it is in too early a stage of development to be able to evaluate its
potential effects on the ecosystem or its fishing efficiency.
· That any new technical measure, which utilises electrical stimulation as a
component, should be accompanied by thorough and rigorous evaluations
as to their potential environmental impact and fishing efficiency at the ear
liest stage possible.
Impact Assessment of the gear modifications
In January 2003, legislation was introduced requiring all fishers in the European
Crangon crangon (brown shrimp) fisheries to use selective gear (sieve net or a selection
grid) that reduces the incidental bycatch of juvenile commercial fish species. Each
member state was responsible for implementing their own legislation enforceable
within their national waters. The efficacy of the UK legislation (The Shrimp Fishing
Nets Order) was evaluated in a multidisciplinary study using social, biological and
economic methods.
The social analysis was used to identify changes in fleet structure and fishing pat
terns since the legislations introduction and the extent of compliance and enforce
ment. The biological analysis evaluated the performance of commercially used
selective gear and also identified changes in fish stocks of bycatch species. The eco
nomic analysis assessed the economic implications of the legislation. The retrospec
tive change in productivity of the brown shrimp fleet as a consequence of the use of
sieve nets was estimated using a production function approach. The analysis utilized
vessel logbook data detailing brown shrimp landings by individual trip during the
period January 1999 to August 2006. The analysis of the two models was performed
using FRONTIER 4.1 and showed a reduction in fleet productivity of 14% following
the introduction of the legislation.
Conclusions
The gear measures introduced into the Crangon beam trawl fisheries have largely
been effective although the introduction of derogations for some fleets has reduced
the effectiveness. This has been a weakness in a number of technical measures regula
tions. This case study also demonstrates that a protocol used to evaluate the efficacy
of these technical measures in the C. crangon fisheries is both holistic and effective.
The same protocol can potentially be used elsewhere in other fisheries to conduct
similar evaluations on the efficacy of technical measures.
References
Catchpole, T. L., Revill, A. S., Innes, J., and Pascoe, S. 2008. Evaluating the efficacy of technical
measures: a case study of selection device legislation in the UK Crangon crangon (brown
shrimp) fishery. ­ ICES Journal of Marine Science, 65: 267­275.
ICES. 2007a. Report of the ICESFAO Working Group on Fish Technology and Fish Behaviour
(WGFTFB), 23­27 April 2007, Dublin, Ireland. ICES CM 2007/FTC:06. 197 pp.

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ICES. 2007b. Report of the ICES Working Group on Ecosystem Effects of Fishing Activities
(WGECO), 11­18 April, 2007, ICES Headquarters, Copenhagen, Denmark. ICES CM
2007/ACE:04. 162 pp.
ICES. 2007c. Report of the Working Group on Crangon Fisheries and Life History (WGCRAN),
22­24 May 2007, Helgoland, Germany. ICES CM 2007/LRC:08. 40 pp.
Polet, H. 2003. Evaluation of bycatch in the Belgian brown shrimp (Crangon Crangon L.) fishery
and of technical means to reduce discarding. Phd thesis, University of Ghent, Belgium.
Revill, A., Pascoe, S., Radcliffe, C., Riemann, S., Redant, F., Polet, H., Damm, U., Neudecker, T.,
Kristensen, P., and Jensen, D. 1999. The economic & biological consequences of discarding
in the European Crangon fisheries. Final report to the European Commission, Contract
No. 97/SE/025.
Revill, A.S. 2001. Technical measures and the North Sea Crangon fisheries. Annex 11. In Evalua
tion of the effectiveness and applicability of technical measures in fisheries management
(TECMES). Final Report (EU Study Contract no. 98/016).
Case study 5 - Pelagic trawling for blue whiting, Faroe Islands
Brief overview of the situation prior to mitigation measures/regulation
Blue whiting (Micromesistius poutassou) is one of the major pelagic fish resources in
the Northeast Atlantic. In 2004 the total recorded catch of blue whiting in the North
Atlantic reached 2 377 569 t mainly taken by Norway, EU countries, Iceland, Faroe
Islands and Russia. The total blue whiting catch in the Faroese EEZ in 2004 was 435
000 t (ICES, 2005). It is thus a highly valuable fishery, although essentially the only
restrictions on this fishery have been in the form of quotas and mesh size.
In the last decade there have huge technical developments in pelagic fishing, both in
vessels size and design, as well as in development of trawl design. Today pelagic
trawls used for blue whiting have horizontal openings of 200 m wide with vertical
openings of 100 m encompassing meshes of 64 m in the mouth of the trawl gradually
tapering back to 32 mm in the codend. These trawls have the ability to catch several
100 tonnes in a few minutes towing time using towing speed of 3­4 knots.
Drivers that initiated gear measures being introduced
In recent years an increasing bycatch of demersal species, mainly saithe (Pollachius
virens) and to a lesser degree cod (Gadus morhua), have been observed in the blue
whiting fishery, particularly in the Faroese area. Preliminary findings at the Faroese
Fisheries Laboratory have shown that the average bycatch of saithe on one vessel in
November/December 2004 was 3.2% in weight per tow (range 0%20%) and in
May/June 2005 2.2% in weight per tow (range 0.6%14.9%) (Lamhauge, 2004, 2005).
The Faroese Fisheries Inspection estimated an average bycatch in Faroese waters to
be approximately 1% with Similar findings have been made in Icelandic waters (Páls
son, 2005). Given the catch sizes in this fishery, these bycatches leaves have the poten
tial to impact on saithe and cod stocks.
For the Faroese pelagic fishermen this bycatch was valueless as it could not be sorted
from the blue whiting catch so given the main problems were in Faroese waters there
was a strong motivation for them to look at ways of reducing saithe and cod catches
to the benefit of the Faroese demersal fleets. Saithe is an important stock to the
Faroese fishing fleet. It was also pointed out by scientists that the bycatch was a
source of an unaccounted mortally in the stock assessment of cod and saithe in the
area, which needed to be addressed. This motivated research into gear mitigation
measures for this fishery.

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Mitigation measures or gear changes tested
Experiments to introduce sorting grids for use in pelagic trawls to solve the bycatch
problem were undertaken in a joint project between the Faroese Fisheries Laboratory,
the Faroese Fisheries Ministry, the pelagic vessel owners and the Faroese gear manu
facturer "Vónin" Ltd. Since 2004 a range of rigid and flexible grids have been tested
to reduce the bycatch. Underwater video techniques have been used to observe the
function of different grids. The original rigid steel grids tested, of similar design to
the successful Nordmore grid used in shrimp fisheries, could not withstand the huge
forces in play in these big trawls. There were also considerable problems with these
grids becoming blocked with blue whiting causing handling difficulties and loss of
catch. Further testing led to the development of a compromise flexible grid made of
plastic tubes mounted on frame ropes. Preliminary results indicated that bycatch
could be reduced by more than 95% without losing more than 1% of the targeted fish
catch. Further testing provided these levels could be consistently achieved. More de
tails are given in Zachariassen and Thomsen (2007).
Management measures introduced after initial research and impact Assessment of the
gear modifications
Following this research on the 1 January 2007 it became mandatory for the Faroese
blue whiting fishery to use a sorting grid in Faroese waters where bycatch is an issue.
The type of sorting grid is not specified, but the bar spacing has to be 55mm. Accep
tance of this gear measure is reportedly high for the Faroese fishing industry and this
has largely been helped with a strong education campaign by the Faroese laboratory
in assisting fishermen with the installation and use of the grid. Grants for purchase
and installation costs have also been instigated. This strong collaboration between the
Faroese fisheries laboratory and the Faroese fishing industry, in parallel with the
technical assistance provided has led to this high level of acceptance of adopting the
sorting grid. The request for this type of project came from the fishing industry, mo
tivating by an understanding that they needed to address the issue of saithe bycatch
or otherwise regulations such as closed areas or restricted catches would have been
imposed upon them. The Russian blue whiting fleet, however, did not adopt the sort
ing grid that well, although communication between the Faroese fisheries laboratory
and Russian vessels is ongoing.
Monitoring of the use of the grid has been intense and as part of the introduction of
the regulation the Faroese authorities have sought to assess the effectiveness of this
measure can through monitoring catches at sea and landings ashore. The monitoring
of the landings reflects whether bycatch levels have been reduced effectively and re
ports suggest this is the case. Any effects on saithe and cod stocks have not yet been
observed given the regulations have only been enforced for 18 months but this is be
ing closely monitored.
Conclusions
The introduction of the flexible grid into the blue whiting fishery shows how gear
measures properly researched with full industry support can work and what is really
interesting about this gear measure is that from inception to regulation took only a
year or so. The Faroese experience shows the importance of industry collaboration
but also the need for back up technical support and education of fishermen to en
courage acceptance. The adoption of this grid is perhaps paralleled to the introduc
tion of Turtle Excluder Devices in the US, Southeast Asia and Australia where
education programmes that have accompanied their introduction to advise fishermen

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on correct installation and handling, as well as provision of back up technical assis
tance to solve rigging and handling problems that may have arisen.
References
ICES. 2005. Report of the Northern pelagic and blue whiting fisheries Working Group
(WGNPBW). ICES CM 2005 (ACFM:05), 241 pp.
Lamhauge, S. 2004. Hjáveiða í flótitroli. Faroese Fisheries Laboratory, Tórshavn. Faroe Islands
(In Faroese).
Lamhauge, S. 2005. Hjáveiða í flótitroli. Faroese Fisheries Laboratory, Tórshavn. Faroe Islands
(In Faroese).
Pálsson, O. K. 2005. An analysis of bycatch in the Icelandic blue whiting fishery. Fisheries Re
search, 73 (2005) 135­146).
Zachariassen, K., and Thomsen, B. 2007. Sorting grids in large bluewhiting trawls. ICES Bos
ton Symposium Fishing Technology in the 21st Century". ICES Journal of Marine Science
(in press).
Conclusions
The integration of fishing gear technology research in the framework for fisheries
management is a prerequisite for achieving an ecosystembased approach. It is rec
ommended that many of the issues evolving from the selected case studies should be
taken into account in a framework for assessing impacts and management measures
related to fishing gear based technical measures.
Fishing gear technologists tend to focus on single or multiple commercial fish species.
With the exception of charismatic species, very little fishing gear research is focused
on nontarget fish species and benthic invertebrates; although such gear modifica
tions might have an effect on nontarget fish and invertebrate species. Most of the
fishing gear research is driven by the fisheries management objectives, which is in its
turn mainly driven by the healthiness of commercial fish stocks. There is gradually a
focus on a more ecosystembased approach, but very few fishing gear research is yet
focusing on other ecosystem components. Therefore there is need to consider biologi
cal and ecological impacts of gear measures during the research phase and before
inception into legislation.
Fisheries gear research has and is focusing on the reduction of physical habitat im
pacts (e.g. EUproject "DEGREE"), but few of these efforts have been implemented in
the actual fisheries and this is reflected in the fact that the authors could not identify a
good case study to address this.
Research on gear modifications to improve selectivity of commercial fish species
through a variety of sorting devices has been proven to reduce bycatch and discards
rates, mainly of fish species (Valdemarsen and Suuronen, 2003, Suuronen and Sarda,
2008). The application of these gear modifications can be achieved through regula
tions or sometimes through the voluntary use by fishermen. Regulatory and market
incentives both can lead to an improvement of fishing practice.
From the case studies, it can be seen that communication and education are vitally,
when introducing gear based measure into legislation. Regulations are in some cases
quickly introduced, but it takes time for the fishing industry to adapt. Case study 5
(blue whiting fisheries and the use of a flexigrid) illustrates that the compliance and
acceptance of gear measures can be high, as a consequence of the involvement of the
Faroese fishing industry in the actual fishing gear research and the implementation of

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the legislation. The first case study (gill net fisheries and the use of pingers) however,
is a clear illustration where the very limited involvement of the fishing industry in
the development of Acoustic Deterrent Devices, its application and implementation
through legislation leads to much scepticism towards its use. The proven positive
effects of acoustic deterrent devices for certain cetacean species and fisheries have
been largely undermined and the measure has been ineffective in meeting its objec
tives.
Another vital aspect for an effective use of gear modifications is a good framing of
the legislation. There is a need to consider all relevant issues (e.g. practicalities, socio
economic and technical aspects, etc.) to ensure that gear measures, proven effective in
fishing gear research, meet their objectives after implementation.
Nonregulatory uptake of technical gear measures can be achieved through several
incentives. The incentives can be marketdriven, but uptake leading to an improve
ment of the fisheries image is also present. One example is the use of the benthos re
lease panel. In this case, the drivers are economic incentives and an improvement the
image of fisheries towards the public perception and supermarkets (achieved
through e.g. the UK Clean fishing competition). The use of selective methods by fish
ermen in other cases is apparent, when fishermen face or are subjected to a reduction
in fishing opportunities through other restrictive measures (e.g. access to closed ar
eas, increase in fishing days, etc.). This has been apparent in the adoption of the
Nordmore grid in Norwegian shrimp fisheries, where fishermen had to adopt more
selective gear to remain I the fishery (Graham et al., 2007).
WGFTFB conclude that the protocol used in the UKstudy (Catchpole et al., 2008) to
evaluate the legislation put into force for the C. crangon fisheries is both holistic and
effective. The same protocol can potentially be used elsewhere in other fisheries to
conduct similar evaluations on the efficacy of technical measures. This protocol in
cludes an evaluation of the legislation text, performance of the gear modifications,
including environmental effects and a socioeconomic evaluation. This can be sup
plemented by evaluating the efficacy of technical measures through proper use of
data gathered under the Data Collection Regulation, e.g. Enever et al. (submitted).
Data collection programmes can be used to evaluate the gear measures put into force.
However, these evaluations have to be used in association with survey data, to
document changes in discards and/or landings/catch.
COM. 2002. Communication from the commission to the council and the European parliament
on a Community Action Plan to reduce discards of fish. 22pp.
Suuronen, P., and Sarda, F. 2007. The role of technical measures in European fisheries man
agement and how to make them work better. ICES Journal of Marine Science, 64: 751­756.
Valdemarsen, J.W., and Suuronen, P. 2003. Modifying fishing gear to achieve ecosystem objec
tives. In: Responsible Fisheries in the Marine Ecosystem, pp. 321­341. Ed. By M. Sinclair
and Valdimarsson, G. FAO, Rome and CABI International Publishing.

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Annex 12: Reports from National Coordinators of the FAO Project
(REBYC 1)
Philippines
Jonathan O. Dickson, Bureau of Fisheries and Aquatic Resources,
jod_bfar@yahoo.com
Abstract
The pilot implementation project was carried out in Samar Sea (Calbayog City) from
September 1, 2005 to December, 2006. The experiment involve 18 units of shrimp and
fish trawl fishing boats were used during the experiment with a total landed catch of
1,295 tons of fish from 991 fishing trips. The average catch perunit effort (CPUE) for
shrimp trawl (panghipon) was just below 1 ton (948 kgs) per fishing trip while CPUE
for fish trawl (palupad) was 2.4 tons per fishing trip. Fishing season (peak months)
was clearly indicated in the months of October and November and lean season in
JulyAugust.
Of the total estimated catch of 711 tons of shrimp trawl for the study period, more
than one third (37.9%) was comprised of lizard fish (lizard fish, Saurida spp), followed
by nemipterids (Nemipterus hexodon, Scolopsis sp., 10%) and about 1% of shrimps. The
rejects, which comprised of the juveniles of commercially important species as well as
other smallsized fish of low or no commercial value and commonly utilized as aqua
culture feed, was 15.6%. The composition of rejects in shrimp trawl indicated high
incidence of juveniles of commercially important species, among which were the liz
ard fish 8.1% (Saurida sp.), purple spotted bigeye 5.4% (Dilat, Priacanthus tayenus),
cardinalfish 9.2% (Muong, Apogon sp., hairtail (espada, Trichiurus sp.).
Shrimp trawl releasing efficiency on rejects/discard according the JTED type with V15
with the highest releasing efficiency of 59%. V10 with releasing efficiency of only 20%
was way below the set target of 40% was rejected during the 1st quarter of implemen
tation. For the commercial fish catch only V15 indicated a reduction of 10%, appar
ently the reason fishermen were hesitant in using the device during the trials. H15
and V10 had an even indicated increase of 11%, while V12 increased by 5%. While,
fish trawl the releasing efficiency on the reject was more apparent on V12, V15 and
H15 with 54%, 58% and 46% respectively. Again V10 with 20% was below the thresh
old. Interestingly, the commercial catch indicated a significant increase on the V15
with 66% higher catch and H15 likewise increase by 18%. Decrease was observes in
V10 and V12 with 23% and 3% respectively.
On sex and maturity of Short bodied mackerel and nemipterids species has a good
data in terms of maturity. The Rastrelliger kanagurta, locally known in Calbayog as
Short bodied mackerel, showed that its longest average length appeared in April with
225mm and its shortest average length in May. The result on the average length is
directly proportional with the highest result on average Gonad Weight and Gonado
Somatic Index (GSI) appearing in April with 3.25 and 2.25 gms, respectively. Matured
samples were likewise observed in April, May and July. Matured samples were fur
ther observed in October and December. Most of the samples were however observed
in April which indicates that summer is the potential spawning season of this species.
While, nemipterids as it is locally known in the area showed that its longest average
length appeared in August with 179mm and its shortest average length in May
(174mm). With regards to average GSI, December showed the peak with 1.91 fol

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lowed by September and October with 1.89 and 1.90 respectively. Similar months
obviously showed the same trend with regards to average gonad weight. The
monthly percentage composition from GSI which was practically based from the five
point maturity scale. Moreover, the majority of the samples gathered were immature
(stages I III). Significant percentage of fully matured samples was observed through
out the sampling period with December showing the highest followed by October
and July, September and November.
Introduction
Trawl is one of the most efficient fishing methods to harvest bottom and midwater
fishery resources. It is considered, however, as a highly nonselective gear due to the
fact that it exploits a wide variety of species in different sizes giving rise to problems
associated with managing fish stocks and maintaining biodiversity. Specifically, the
high proportion of small juvenile fish in the catch of trawls aggravates the current
serious problems of overfishing in most of fishing areas. Catches of juveniles and
other noncommercial lowvalue species in large portions which are utilized and
thrown out to the sea as discards are deplorable considering the current overfished
state of coastal fishing grounds.
However, the effectiveness of contemporary measures regulating mesh size and area
of fishing ground restrictions has large been acknowledged to be impractical and in
adequate. Given that trawling is a major fishery and will likely remain an important
sector in countries like the Philippines, it is important that methods or devices to
make it a more selective by reducing the incidence of juvenile and trash fish captured
are introduced in order.
Regulating mesh size and shape is a direct measure enforced for conservation of fish
ery resources. The minimum legal stretched mesh size is not less than 3 centimetre
and above between two opposite knots of a full mesh when stretch (BFAR FAO No.
155, 1986). For trawl fisheries, the optimum mesh size is very difficult to obtain due to
high diversity of catch. Shrimps may represent as little as 10% of the total catch
(Ramiscal, 1996) which also happen in other trawl tropical countries (Seidel, 1975).
Likewise, the operation of trawl is also delimited by fishing ground restrictions. Un
der the Fisheries Administrative Order 201, the operation of active fishing gears in
cluding trawls is not permitted within the municipal waters or within 15 kilometres
from shore.
Trawl by and large remains an important source of food, income and employment to
a significant sector in the fisheries in the country. In 1992­1995, the fishery contrib
uted an average of 83,000 MT or 10% of the total commercial fisheries and 32,000 MT
or 4.3% of the municipal fisheries. Widespread trawl operations, mainly for shrimps
are known to exist in moderately deep inland seas, bays and other coastal areas, no
tably Visayan Sea, Samar Sea/Maqueda Bay, Lingayen Gulf, San Miguel Bay/ Polilio
and Waters of Palawan. Due to overfishing problems in many areas, active fishing
gears including trawls have been prohibited in municipal fishing grounds or within
15 km from the shoreline.
Several efforts have been made to introduce or study methods or devices to exclude
or dissociate juveniles and other nontarget or unwanted catch from the target of
commercially important species thereby reducing the impact to resources and biodi
versity. Among these are the square mesh codend and Bycatch reduction devices
(BRDs), including the turtle excluder device (TED) and juvenile and trash fish ex
cluder devices (JTEDs). JTEDs being promoted by the Southeast Asian Fisheries De

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velopment Center (SEAFDEC) Training Department under its 5year ASEAN
SEAFDEC Plan of responsible fishing technologies and practices. Experiments have
been carried out in most countries in Southeast Asian Region (Thailand, Brunei Da
russalam, Vietnam, Indonesia, and Malaysia) where encouraging results in certain
designs have been indicated.
The project in the Philippines is parallel project to introduce and promote selectivity
devices to reduce the incidence of juveniles and trash fish and which can supplement
existing management measures in shrimp trawl fishery. The project is being imple
mented in collaboration with FAO/UNEP/GEF, under Project EP/GLO/201/GEF enti
tled "Reduction of Environmental Impact from Tropical Shrimp Trawling Through
the Introduction of Bycatch Reduction Technologies and Change of Management".
This paper covers the results of initial experiments conducted in Manila Bay, San Mi
guel Bay, Samar Sea, Visayan Sea and Lingayen Gulf, considered as the leading fish
ing grounds for shrimp trawl in the Philippines.
Methods
1. Duration and Scope
The pilot project started in September 2005 involving 30 vessels that have been al
lowed to operate under the Coastal Zoning Project; however, the 1st quarter re
view/evaluation in December 2005 necessitated revision of the implementation plan
to incorporate clear and expanded effort control system. The revised plan was subse
quently implemented starting April 2006 until December 2006. It involved 18 opera
tional vessels; each allowed 5 fishing trips per month (maximum of 3 fishing days per
trip) instead of the potential 7­8 fishing trips which each vessel can achieve per
month. A dispatching system was devised for the departing vessels to acquire clear
ance from the City Agriculture Office.
In JanuaryMarch 2006, while the revised pilot project was awaiting approval from
concerned parties, the catch and effort was likewise monitored even while the fleet
was not using JTED.
2. JTED variations and deployment
Vertical sorting grids 10mm, 15mm (V10, V15) and horizontal sorting grid (H15) were
used in September 2005Decemeber 2005. After the 1st quarter evaluation indicating
poor performance of V10, the working group recommend vertical sorting grid 12mm
(V12) as replacement, thus V12, V15 and H15 were utilized from AprilJune, 2005.
Subsequently in JulyDecember 2006, only V12 and H15 were utilized to V15 high
exclusion of commercial largersized fish which became unacceptable to participating
fishermen. Control vessels (no JTED) were maintained during the entire study pe
riod.
JTED variations and control were alternated and deployed on rotation basis among
participating vessels (See appendixes for deployment pattern in SeptDecember 2005;
AprilJune 2006; JulyDecember 2006). No JTED was used between JanuaryMarch
2006 when the implementation of the pilot project was deferred.
3. Data gathering & sampling
a ) Fish landing survey/monitoring
Daily fish landing/unloading was conducted at Calbayog Fish Port. In September to
December 2005, sampling was scheduled every two days and subsequently pro

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gressed daily sampling or total enumeration in the remaining period of implementa
tion. Data collected included total catch and species composition. Subsampling was
done on dominant and commercially important species.
In order to determine the effect of the devices, the catch was classified according to
general grouping as follows:
· Commercial fish ­ all fish of commercial value or those that are usually
sold; and further subgrouped as large, medium, small according to size
groups or classification used for wholesale pricing.
· Reject ­ catch that is sold as fish food in aquaculture.
Size grouping (large, medium, small) of dominant commercially important species
was also determined. Length measurements for dominant species were done.
On a particular sampling day, sampled boats were selected in a random manner as
much as possible, however, historically vessels with accommodating operators were
provided precedence to be able to gather more reliable information and execute the
designed sampling procedures. Two (2) predesigned forms are filledup in one sam
pling day.
For a particular sampled boat, the total boat catch (weight) was determined by count
ing the number of tubs and appropriately raised by the established weight per con
tainer as it was virtually impossible and impractical to individually weigh their
contents. Normally, catch were usually landed presorted by species by the fishermen
onboard to which the volume was recorded for that species and in instances where
sorting was done according to group, size or mixed species and trashfishes/rejects. In
cases of mixed species, the composition was determined by the subsampling method
and appropriately raised to the total number of boxes and recorded accordingly in
prescribed form (Form 1).
In case of mass landing and total sampling is unworkable, the total boat catch and
fishing effort for each unsampled boat were simply inquired from masterfisherman
or the person in charge of catch disposal at the port and recorded in Form (2).
b ) Total landed catch and effort
On a regular sampling day, the total landed catch and effort of both sampled and un
sampled boats as well as the species composition of sampled boats are summarized.
The catch composition of the total landings of the particular sampling day is raised
according to the observed catch composition of the sampled boats. The catchperunit
effort (CPUE) was expressed as the kg/boat/trip.
c ) Length frequency
On any instance, subsampling was randomly and proportionately undertaken from
fish tubs for length measurement of the species caught or in some instances, the ma
jor species and recorded in Form (2). The total length to the nearest cm was used as
the standard measurement in this project. After measuring, the frequencies are then
raised according to the total catch of the sampled boats and subsequently encoded
and analyzed via FiSAT Software. Moreover, the length frequency data were used in
the determination of some biological and population parameters such Length Infinity
(L), growth increment per (k) year using the ELEFAN 1 (k scan, response surface and
automatic search). The data was likewise used in analyzing the number of pulses (re
cruitment) per year per species.

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Moreover, these data obtained from the ELEFAN 1 were used in the estimation of F
(Fishing Mortality), M (Natural Mortality), Z (Total Mortality) and the E (Exploitation
Rate) of some selected species. Consequently, recruitment patterns determining the
number of pulses or obtaining the plot showing the seasonal pattern of recruitment,
Probability of capture (25%; 50% and 75%).
d ) Gonad maturity
The examination of 50 samples/tails for the five major species in Calbayog City which
were taken from sampled boats every month was realized. Total Length, measured in
millimetre as well as body and gonad weight were determined which are rounded to
the nearest 0.1 grams were used in the determination of spawning month for the en
tire study period. Sex and gonad stage were determined through visual inspection
using the standard 5point maturity scale respectively. These data are used in deter
mining the Gonado Somatic Index (GSI) of the five major species which are used to
validate the spawning month of the selected species. Furthermore, the Gonad weight
multiplied by the body weight and 100 was the key in determining the GSI which
likewise served as the basis in the determination of Length at first maturity of the
sampled species through the practical method.
e ) Biomass estimation and catchperunitarea (CPUA)
In determination of the Biomass and CPUA, data items recorded include the fishing
boat speed, wing spread of the gear, the coordinates, species composition by weight
and fishing effort (time) including the total Samar Sea Area. In principle, it appears
that a trawl sweeps a well defined path which is called the "swept area" or the "effec
tive path swept". The swept area was estimated by using the formula a=D*hr*x2.
The CPUA was determined by dividing the catch by the swept area (in NM or square
kilometres. Moreover, the biomass was determined by the formula where B is the
Biomass, Cw/a is the mean catch per unit area, A is the total size of the area under
study and X1 is the fraction of the biomass in the effective path swept by the gear
which is actually retained in the gear. In recent studies, x1 ranges between 0.4 to 1.0.
In this study however, 0.5 was used which appears to be the most widely used value
in Asian survey activities.


As per recent onboard activities, the duration of each haul averages to be 2.4 hours
for Fish Trawl and 4.7 hours for shrimp trawls. The duration of the haul is propor
tional to the distance covered so the effort has no direct influence on the catch per
unit area (CPUA)
Onboard observation
Onboard observation was once a month starting April 2006 to monitor compliance to
JTED deployment. Biological data includes species and size composition. Dissection
to determine sex and maturity of major species caught was likewise conducted.
Logbook system
In an initial effort to determine the effect of the devices and pilot project scheme on
the operation and income, logbooks accomplished by owners of participating vessels

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were evaluated. Logbooks entries included catch/production, cost of operation and
proceeds from sales.
Clearance/dispatching system
Participating vessels were required to secure a Clearance or Sailing Order from City
Agriculture Office (CAO) as a manner to enforce the devised effort control. Clearance
or Sailing Order included certification of inspection of JTED and specified dates of
departure and return to port.
Agencies involved and responsibilities
i )
Working Group
The working group was organized as the steering and implementer of the pilot pro
ject. Among others, its responsibilities were to plan, coordinate and ensure proper
implementation. It was composed of representatives of LGU Calbayog City, BFAR
CO Project Team, BFAR RFO8 /RFTC8, OPASamar, CAFC, PAFC, APCO Samar and
the Fishing Boat Owners/Operators of Calbayog City. Its main responsibilities were
of the Pilot Project
ii )
Local government unitCalbayog City
As coproject implementer, among others, the responsibilities of the LGUCalbayog
City were to arrange authorized/acceptable implementation among local stake
holders, to ensure participation of selected Commercial Fishing Boats (CFBs) in Cal
bayog City and complement in the enforcement of related laws/regulations
iii ) BFARCO Project Team
As coproject implementer, the responsibilities of the BFARCO Project Team were to
provide financial support on activities supported by FAO/GEF Project, provide
JTEDs to be used and technical requirements and support during the entire imple
mentation of the project
iv ) Fishing boat operators and fishermen
As cooperators, the boat owners and crew were agreed to be responsible for full
compliance with the conditions of the implementation plan including provision of
required data and allowing researchers/enumerators to join fishing trips.
v )
Periodic review/evaluation
A quarterly review and evaluation spearheaded by the working group was agreed to
update concerned parties on the project implementation and address emerging issues
and concerns as a condition to the continued implementation of the pilot project.
Results
Total catch and effort
For the period September 2005 to December 2006, the trawl fleet based in Calbayog
City landed a total catch of 1,295 tons of fish from 991 fishing trips. The average catch
perunit effort (CPUE) for shrimp trawl (panghipon) was just below 1 ton (948 kgs)
per fishing trip while CPUE for fish trawl (palupad) was 2.4 tons per fishing trip.
Fishing season (peak months) was clearly indicated in the months of October and
November and lean season in JulyAugust.
It is notable that fishing effort was significantly reduced beginning in April when
supplementary effort control was introduced.

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Catch composition and seasonality
The total estimated catch of 711 tons of shrimp trawl for the study period, more than
one third (37.9%) was comprised of lizard fish (lizard fish, Saurida spp), followed by
nemipterids (Nemipterus hexodon, Scolopsis sp., 10%). Shrimps which are considered as
the target species formed just about 1% of the catch. The discards comprised of juve
niles of commercially important species, as well as other smallsized fish of low or no
commercial value and commonly utilized as aquaculture feed was 15.6%.
The composition of discards in shrimp trawl indicated high incidence of juveniles of
commercially important species, among which were the lizard fish 8.1% (Saurida sp.),
purple spotted bigeye 5.4% (Dilat, Priacanthus tayenus), cardinalfish 9.2% (Muong,
Apogon sp., hairtail (espada, Trichiurus sp.).
For fish trawls, the catch was dominated by small pelagic species e.g. roundscad
47.8% (GG, D. maruadsi), sardines 10.8% (tamban, Sardinella longiceps) and mackerel
7.8% (short bodied mackerel, R. faughni). Demersal fish which are the dominant catch for
shrimp trawl constitute a small portion of the catch like lizardfish (lizard fish) 0.4%
and threadfin bream 0.3%. The reject portion of the catch was also comparatively
lower, with only 4.2% of the total catch
JTED efficiency by catch grouping
TheV15 JTED gave the highest release efficiency with 59% reduction of re
jects/discards. V10 with releasing efficiency of only 20% was way below the set target
of 40% was rejected during the 1st quarter of implementation for the commercial fish
catch. Only V15 indicated a reduction of 10%, apparently the reason fishermen were
hesitant in using the device during the trials. H15 and V10 had an even indicated in
crease of 11%, while V12 increased by 5%. In terms of total catch, V12 and V15 had an
overall reduction effect on the catch with 3.5% and 19.8% respectively.
For fish trawl, the release efficiency for rejects was more apparent on V12, V15 and
H15 with 54%, 58% and 46% respectively. Again V10 with 20% was below the thresh
old. Interestingly, the commercial catch indicated a significant increase on the V15
with 66% higher catch and H15 likewise increase by 18%. Decreases were observed in
V10 and V12 with 23% and 3% respectively, and the total catch, V12 showed a signifi
cant increase in catch with 58% increase as compared to control net. H15 increased by
4% while there was a decrease in V10 and V12 with 23% and 6% respectively. It was
surmised that the increase in V15 and H15 was attributed to less drag due to release
of smaller fish and less masking on the codend.
Potential effect of JTED utilization on catch and income
To be able to demonstrate the potential impact of the devices on the catch and income
on shrimp trawl, a simple projection is shown in Table 1 as computed based on the
following:
· Total fishing effort = total fishing effort made by the shrimp trawls in 2006=
455 trips
· Total catch = average NOJ catch rate = 930.15 kgs/trip
· Catch composition = NOJ composition (reject, commercialfurther classi
fied into small, medium, large)
· Reduction/ increase
· Reject = Average reject reduction / increase by JTED type

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ICES WGFTFB REPORT 2008
· Large commercial = average large commercial reduction/increase on lizard
fish by JTED type
· Medium commercial = average medium commercial reduction/increase on
lizard fish by JTED type
· Small commercial = average small commercial reduction/increase on lizard
fish by JTED type
· Weight increase of small commercial fish = 3 times in 6 months period
· Average price (pesos)
· Large commercial = 60
· Medium commercial = 40
· Small commercial = 30
· Reject = 5
Table 1. Projections of loss or gain from released juveniles and discards from catch.
NQJ
v10
v12
v15
h15
Income from large fish
11,964,015
8,500,135
19,169,717
11,179,643
14,290,961
Income from medium fish
3,214,394
3,273,203
2,360,645
2,410,188
2,767,419
Income from small fish
1,648,777
2,297,024
1,081,611
602,547
1,249,731
Income from rejects
442,504
353,134
275,767
183,612
257,351
Total Income
17,269,690
14,423,496
22,887,739
14,375,990
18,566,462
Loss/Gain of income from large

3,463,880
(7,205,701)
784,372
(2,326,946)
fish
Loss/Gain of income from

(58,809)
853,749
804,206
446,975
medium fish
Loss/Gain of income from small

(648,247)
567,166
1,046,230
399,046
fish
Total loss of income

89,371
166,738
258,892
185,153
Potential value of escaped small


3,402,988
6,277,381
2,394,276
fish
Potential value of escaped reject

804,336
1,500,639
8,607,409
1,666,381
commercial fish
Total potential increase in

804,336
4,903,637
8,607,409
4,060,657
income
Potential production from small


56,717
104,623
39,905
fish
Potential production escaped

13,406
25,011
38,834
27,773
reject commercial fish (25%)
Total potential increase in

13,406
81,727
143,457
67,678
production
Based on the above the following total catch by JTED type was estimated:
Sex and maturity
Rastrelliger kanagurta, locally known in Calbayog as Short bodied mackerel, showed
that its longest average length appeared in April with 225mm and its shortest average
length in May. The result on the average length is directly proportional with the
highest result on average Gonad Weight and GSI appearing in April with 3.25 and
2.25 gms respectively.

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The monthly percentage composition from GSI, which was practically based from the
five point maturity scale. Sample GSIs were classified according to gonad weight
where stages 4 and 5 were classified as fully matured while stages 1, 2 and 3 were as
it is. Majority of the samples gathered were immature while a percent of fully ma
tured samples were observed from April to December except June where there were
no samples gathered.
The percent maturity of samples based from practical determination of maturity from
GSI of 4. It further shows that a very significant portion of catch weighed less than 0
GSIs, with majority caught in May. Matured samples were likewise observed in
April, May and July. Matured samples were further observed in October and Decem
ber. Most of the samples were however observed in April which indicates that sum
mer is the potential spawning season of this species.
The male and female catch maturity per month of short bodied mackerel. It shows
that MI and FI Short bodied mackerel are the most dominant through out the sam
pling period followed by MII and MIII. Matured Male (MIV, MV) and Female (FIV,
FV) Short bodied mackerel are observed to be significantly few. However, FV and
MV are observed to be abundant in July (14n) and April (7n) respectively.
Based from the practical determination of samples through the GSI limit of 4, it was
observed that majority of the male and female of this species appeared immature
through out the pilot project period with a minimal number of matured female ap
pearing in April and May as well as in December. May, October and December is the
appearance of insignificant number of male species.
The figures above both show that most of the catch during the entire sampling period
were sexually immature with the majority appearing in the months of July to Sep
tember. Significant number of sexually matured Short bodied mackerel was observed
during the summer months and also in the last quarter which further validates re
lated above figure that these times of the year are their spawning period.
For nemipterids species in Calbayog city showed that its longest average length ap
peared in August with 179mm and its shortest average length in May (174mm). With
regards to average GSI, December showed the peak with 1.91 followed by September
and October with 1.89 and 1.90 respectively. Similar months obviously showed the
same trend with regards to average gonad weight.
The majority of the samples gathered were immature (stages I III). Significant per
centage of fully matured samples was observed throughout the sampling period with
December showing the highest followed by October and July, September and No
vember.
Lessons Learned
· Affect in some of fishermen in the short term?
· Discuss what Juvenile and Trashfish Excluder Devices (JTEDs) design has
the highest releasing efficiency?
Future Plans
· Demonstration and pilot trials of Suripera
· Policy formulation on the use of Juvenile and Trashfish Excluder Devices
(JTEDs) in commercial and smallscale trawl fisheries
· Consultations with various stakeholders affected by the policy

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ICES WGFTFB REPORT 2008
· Presentation and justification of the policy to the National Fisheries and
Aquatic Resource Management Council (NFARMC) for approval
· Assessment, review and evaluation on the implementation of the policy
· Support to local government units for the management of coastal fisheries
resources through responsible fishing operations and practices
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Thailand
Bundit CHOKESANGUAN, Southeast Asian Fisheries Development Center/
Training Department (SEAFDEC/TD),Post Box 97, Phrasamutchedi, Samut
prakan, 10290, Thailand [Tel:+66 2 4256120, fax:+66 2 4256110­11, email:
bundit@seafdec.org]
Abstract
The promotion and experimental fishing trials on the escapement of juveniles and
trash fish from the trawl fishing gear using JTEDs in Southeast Asian waters was im
plemented in the national waters off Brunei Darussalam, Cambodia, Indonesia, Ma
laysia, the Philippines, Thailand, Vietnam and Myanmar. In order to continually
build up the resource user's awareness, there were some workshop/seminar/training
courses conduction, and information dissemination to the public through web
sites,VCD and publications. There were two main types of technical evaluation of
JTEDs demonstration and promotion were carried out; 1) the scientific data collec
tion, the result and its interpretation was used for further modification of the divide.
2) The awareness and capacity building evaluation by using questionnaires and
dockside interview. Base on situation and lesson learned from the past, there are
some future plans to emphasize in research, development and promotion on the use
of selective fishing gears and devices for reduced discards and bycatch of juvenile
and trash in the region.
Introduction
The people in the Southeast Asian Region have greatly and historically depended on
the fish in their diet. Therefore, fisheries can not be replaced by an alternate system to
secure protein in food including livestock products. In this connection, the fisheries
sector as a whole has been developed into a traditional and complex system com
pared with any other part of the world except the Far East. The Southeast Asia Coun
tries are located in the tropical zone, fisheries resources are of comparatively multi
species composition especially in demersal stocks. In addition, dominant species do
not compose the majority of catch, as in the fisheries in the Temperate Zone (domi
nant species compose 70­80% of the catch in the Temperate Zone; those of tropical
fisheries compose 20­30% of the catch.). It has been recognized that there are big
amount of bycatch are discarded from commercial fisheries especially shrimp and
fish trawling which due to the poor selectivity of the finemeshed nets. Moreover, the
incidental catch of juvenile and trash fish is acknowledged as an important adjunct to
fisheries management. Recently, this aspect has developed to a major issue in fisher
ies management, attributed to an increasing demand for fisheries resources and a
growing recognition of the need to ensure that fisheries are conducted in a sustain
able manner.
Methods
In the development of sustainable fisheries, reducing the incidental catch of juvenile
and trash fish is a key priority. In responsible to this, the Training Department (TD)
of the Southeast Asian Fisheries Development Center (SEAFDEC) initiated research
in 1998 to provide a technical foundation for the development and adoption of Juve
nile and Trash Excluder Devices (JTEDs) in regional trawl fisheries. The promotion
and experimental fishing trials on the escapement of juveniles and trash fish from the

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trawl fishing gear using JTEDs in Southeast Asian waters was implemented in the
national waters off Brunei Darussalam, Cambodia, Indonesia, Malaysia, the Philip
pines, Thailand, Vietnam and Myanmar. Moreover, in order to continually build up
the resource user's awareness, there were some workshop/seminar/training courses
conduction, and information dissemination to the public through websites and the
local people in each countries through VCD and publications such as poster, book
lets, cartoon books, stickers, etc and TD have been provided information through the
website.
There were two main types of technical evaluation of JTEDs were carried out:
· The scientific data collection, each time of the experiment in each men
tioned country names, various kinds of JTEDs in different design and size
of the grid interval were used in the experiments in order to make the
comparison on their effective performance in maximizing the juvenile es
capement while minimizing the loss of the commercial or the target catch.
Base on the results analysis and the interpretation of the collected data
from each fishing ground and each country, the best performance from the
research was used for further modification for the better performance.
· The awareness and capacity building evaluation by using questionnaires
and dockside interview. The evaluation process was carried out in each
area/country.
Results of the implementation and promotion on the use of JTEDs in Southeast Asia
Brunei Darussalam, JTED was introduced and experiment in 2000 and 2002. The 51
mm squaremesh experiment gives better result than the rigid sorting grid type in
term of releasing the unwanted portion of the catch in this country.
Cambodia, in 2004, the Department of Fisheries had closed cooperation with SEAF
DEC/TD for training at Sihanouk Ville. The training was focused on the theory on the
used of JTEDs and practice on installation of JTEDs devices.
Indonesia: JTEDs promotion and demonstration were carried out many times in In
donesia. They have found that the JTED Semicurve rigid sorting grid with 1.5 cm of
grid interval is most applicable for the fish trawl in their country. And Indonesia will
focus on the technology modification of JTEDs construction, mesh figure (diamond or
square).
Malaysia: The experiment was conducted at Kedah water to compare the effective
ness of fishermen net The results found that the 38 mm at codend can be improve
the selectivity of gear and not reduce the rate of commercial catch.
Myanmar: The JTEDs can be applied to use for both fish and shrimp trawls, specially
the window type JTED with 1 cm of bar spacing. But most of the fishermen do not
want to loss their profit. So that they still do not use it in their trawls.
The Philippines: Training/demonstrations and sea trials of JTEDs were done in the
major trawling ground of the country: Manila Bay, San Miguel bay, Lingayen Gulf,
Visayan Sea and Maqueda bay/ Samar Sea. The JTED pilot project was proposed to
the local government unit of Calbayog City to complement the ongoing Coastal Zon
ing Program in which locally based commercial fishing boats including trawlers were
allocated to operate a specific area. Not only seminar, experiments to find the most
applicable design of the device but the activities and promotion of by catch reduction
technologies were also broadcast through the local radio station in Daet, Camarines
Norte.

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Thailand: JTEDs experiments and promotions in the Gulf of Thailand water. The ex
periments and the promotions led to the identification of the Rigid Sorting Grid De
vices as an effective tool in order to release the juvenile and trash from the trawl
fishing. The technical report and techniques were transferred to DOF however it also
depends on the national policy in order to further continue the JTEDs promotion in
Thailand.
Vietnam: The experiment of JTEDs on shrimp trawler was carried out in the Gulf of
Tonkin. Vietnam continues to do the research and experiments by using square mesh
of 20,25,30,35 and 40 mm and iron frame for comparison. The result found that the
square mesh with 20 mm give the best performance on gear selectivity specially for
squid, lizard fish and cuttlefish and economic advantage while Iron frame with 12
and 20 mm is suitable for croaker and lizard fish group.
Lesson learned
Designs and Experiments
· Existing types and designs of JTEDs are not appropriate / applicable in
some geographical areas and species composition that require some adap
tation/modification.
· High cost of JTEDs (Sorting Grids) particularly in smallscale trawl fisher
ies and it needs further research on more viable designs/type of JTEDs.
· Insufficient government support in research and development on the de
vices.
Fishers' perceptions/attitudes/concerns on adoption of JTEDs
· High demand for trash fish such as for feeds for aquaculture.
· Inconvenient operation of the gear equipped with the devices i.e. net haul
ing.
· Reduction of total catch which it may be due to the design and fishing
method of JTEDs use in some areas.
· Higher cost of operation for the fuel oil use during towing.
Awareness Building and Extension Activities
· Limited awareness building and capacity building activities for fishers to
support the implementation.
· Convincing power of the studies/experiments' results to fishers ­ this may
be due to the manner that fishers are involved in the conduct of such stud
ies/experiments.
Promotion and Adoption Strategies
· Linkages between JTEDs and management in several countries.
· Enabling environment/incentives for adoption of such devices by fishers.
· Clear evidence on the escapement of fish as it's can sustain the resources.
Future Plans
Base on situation and lesson learned from the past, there are some future plans to
emphasized in research, development and promotion on the use of selective fishing
gears and devices for reduced discards and bycatch of juvenile and trash in the re
gion including.

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ICES WGFTFB REPORT 2008
· Promotion on the use of selective fishing gears and selective devices as
well as Awareness/capacity building in some selected areas should be con
tinued. Two main target groups need to be focused ­ fishers for their un
derstanding, cooperation and compliance, and policymakers for
understanding on linkages with broader management and supports. The
information dissemination can be done by workshop, exhibition, publica
tion and multi media.
· Research and study of the assessment of impacts of various kinds of fish
ing gear and practice on fisheries resources, sea beds, environment and
ecosystem through impacts of light fishing on fisheries resources in South
east Asia and impacts of bottom trawl net, dredges, traps and other need
to be continued study. Further more the exited device as JTEDs need fur
ther adaptation for better efficiency performance and lesser cost of towing
operation.
· Interaction between threatened species of international concern and fisher
ies and participation of international meetings for information exchange on
interaction of endangered species and fisheries is one of activities in this
project.
The promotion of responsible trawl fishing practices in Southeast Asia
through the introduction of Juvenile and Trash Excluder Devices (JTEDs)
Abstract
The demonstrations and experiments on the use of JTEDs were conducted in Thai
land, Brunei Darussalam, Vietnam, Malaysia, the Philippines, Indonesia and Myan
mar. Aside from the main aim on the introduction of the devices to member
countries, the research was also carried out to develop adjust and modify for the best
performance of the Juvenile and Trash Excluder Devices (JTEDs). Various kinds of
JTEDs were used in the experiment; there are Rigid Sorting Grid, Rectangular shaped
window and Semicurved window with different grid intervals for each device. The
results show that each type and design of JTEDs gave different performance on es
capement rate of juvenile and commercial catch. The escapement rates ranged from
56.69­77% for juveniles and 9.72­47.31% for the commercial or target catch. Further
more the estimated selection curve of fish length was also considered. Based on this
experiment the Rigid Sorting Grid with 1.2 and 2 cm grid intervals gave better per
formance than other devices in maximizing the juvenile escapement while minimiz
ing the loss of commercial or target catch. The mean total length (TL) paralleled to the
size of the grid interval. It is recommended that the Rigid Sorting Grid with 1.2 and 2
cm grid intervals is appropriate to recommend to the region. However, other impor
tance factors such as the fishing ground, kind and size of target catch in each country
have to be well considered.
Keywords: escapement, juvenile devices, JTEDs, performance, rectangular window,
rigid sorting grid, selection, semicurved window, Southeast Asia, trawl.
Introduction
The incidental catch of juvenile and trash fish is acknowledged as an important ad
junct to fisheries management. Recently, this aspect has developed to a major issue in
fisheries management, attributed to an increasing demand for fisheries resources and
a growing recognition of the need to ensure that fisheries are conducted in a sustain
able manner. Once considered mostly as a nuisance, the catch of juvenile and trash

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fish are now recognized as having a detrimental impact on the fecundity of fisheries
systems. Similarly, the economic value of the catch of juveniles of commercially im
portant species are now viewed as being considerably lower than those for the same
species at sizes more suited for the market.
In the development of sustainable fisheries, reducing the incidental catch of juvenile
and trash fish is a key priority. In response to this, the Training Department (TD) of
the Southeast Asian Fisheries Development Center (SEAFDEC) initiated research in
1998 to provide a technical foundation for the development and adoption of Juvenile
and Trash Excluder Devices (JTEDs) in regional trawl fisheries.
At first, two JTED types were developed for installation into the upper part of the
codend. One device used a rectangular shaped window, whilst the other a semi
curved window. The frames of both were constructed using stainless steel frames of
80 by 100cm, with "soft" vertical separator gratings made of 8 mm. polyethylene
rope.
The general effectiveness of those JTED types was tested during atsea fishing trials
and demonstrations. Those designs have since been modified in response to more
detailed testing on their efficacy influenced by various factors including the separator
spacing, "soft" versus "hard" separator gratings, and the use of square mesh in the
codend as opposed to diamond mesh. Investigations were conducted on the effect of
trawl towing speed, catch loading and hydrodynamic drag on deformation of trawl
netting and the ultimate performance of JTEDs, Those tests provided TD researchers
with an insight on the operational considerations required to maximize the exclusion
of juvenile and trash fish from the trawl fishing gear.
Since 1998, TD has completed numerous experimental fishing trials on the escape
ment of juveniles and trash fish from the trawl fishing gear using JTEDs in Southeast
Asian waters. Work has been completed in the national waters off Brunei Darussa
lam, Indonesia, Malaysia, the Philippines, Thailand, Vietnam and Myanmar.
Materials and methods
Study areas: Experiments were carried out in the Prachub Kirikan and Chumporn
provinces in the Gulf of Thailand, the Northern part of Brunei Darussalam, the gulf
of Tonkin in Vietnam, off Alor Setar in Malaysia, Arafura Sea in Indonesia, Manila
Bay in the Philippines and Thandwe town Myanmar.
Types and Designs of JTEDs: The experiments on the performance of JTEDs was
conducted in different countries using different type and design in each study sites,
Once the experiments were done, the adjustment and modification of JTEDs designs
will be made in order to maximizing the juvenile escapement while minimizing the
escape of commercial or target catch. The usual grid separator system consists of
grids, a fish outlet and a funnel which guides fish and shrimp against the grid, (Tokai
T at al., 1996). The types of JTEDs experimented in each country are: Thailand Rec
tangular shaped window with four grid intervals of 8, 12, 16, and 24 cm, Semicurved
window with 4, 6 and 8 cm grid intervals. Brunei Darussalam Rigid Sorting Grid
with 1, 2 and 3 cm grid intervals, Semicurved window and Rectangular shaped win
dow with 1 cm grid interval. Vietnam Rigid Sorting Grid with 2, 3 and 4 cm grid in
tervals. Malaysia Rigid Sorting Grid with 1.2 and 2 cm grid intervals. Indonesia
Rigid Sorting Grid, Rectangular shaped window and Semicurved window with 4 cm
grid interval for all types. The Philippines Rigid Sorting Grid with 1, 2 and 3 cm grid
interval, Rectangular shaped window and Semicurved with both 1 cm grid interval.

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Myanmar Rigid Sorting Grid with 1, 2 and 3 cm grid intervals, Semicurved window
and Rectangular shaped window with 1 cm grid interval.
Fishing operation
Each type and design of JTEDs was installed individually on fish trawler. The cover
net was used to collect samples of the catch escapement. Fishing operations were
scheduled and carried out during both day and night times with an hour of towing,
each size of grid interval designs was tested for 5­9 times in fishing operation.
The catch categorization
The catch of each haul from both codend and cover net was sorted mainly into 2
main groups; commercial or target catch and juvenile including trash groups. The
samples taken randomly from each group were determined for their individual
weighed total length (TL) and body width (BW) in cm. The catch of each group was
also weighed for calculation of CPUE and percentage of escapement rate.
Data Analysis
Rate of escapement: In order to consider the most appropriate performance of JTEDs,
the important factors which need to be considered are the rate of escapement of juve
niles including trash fish and the commercial catch. The purpose of the device is to
maximize the catch of juvenile and trash fish while minimize the rate of escapement
for the commercial and target group:
The rate of escapement was calculated by using the following equation:
E = (Wcn/(Wcn+Wce))*100
Where E = Escapement rate by weight in %
Wcn = Catch in cover net (gm)
Wce = Catch in codend (gm)
Selectivity
The estimate of trawl net selectivity curve was determined using a linear model. This
method is the most commonly used by comparing the length compositions of the fish
remaining in the codend and in the cover net, the probability of escape through the
large mesh net can be estimated, (Pope et al.,1975, Jones, 1976, Kimura, 1977 and
Mastawee and Theparoonrat, 2002) .
Linear model:

Trawl selection curve was approximated by the following equation.
S=1/{1+exp(a+b*l}
(2)

Where, l is the total length of the fish and a and b are constants.

The log equation is linearizes the relationship.
Ln(1/S1)=a+b*
In this model, the parameter is estimated by minimizing the following
n
[ln{(1/S)1}(a+b*l]2
i=1

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ICES WGFTFB REPORT 2008
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From equation 4, the regression coefficient "b" is obtained as.
b= [(ll)(YY)]/ (ll)2
Where y = ln[(1/S)1], and y is average. The intercept "a" is calculated by the follow
ing equation.
a= ybl
Results and discussion
1 ) CPUE comparison
The CPUE among different countries ranged from 8.45 to 283.27 kg/hr. The re
sults show that the CPUE from Brunei Darussalam, Indonesia, Myanmar, Ma
laysia, Thailand, Philippines, and Vietnam was 283.27, 99.75, 86.03, 35.81, 21.2,
14.7, and 8.45 kg/hr respectively. The highest one was found in Brunei Darus
salam, which indicates that the fisheries resources at the experiment site in
Brunei Darussalam are still very rich compared to sites in other countries.
2 ) Rate of escapement
The relative mean escapement rates according to JTEDs types from each study
sites are shown in Figures 1­7.

Experiment on types of JTEDs in Thailand
Experiment on type of JTEDs in Vietnam
) 70
)
%
30
%
60
e (
25
t
e (
at 50
a 20
t
R 40
t
R
en
15
30
en
em
10
20
em
10
5
scap
scap
E
0
E
0
R ec .8
R ec .12
R ec .16 R ec .24
Semi. 4
Semi. 6
Semi. 8
Semi.12
R S2
R S3
R S4
Design of JTEDs
Com. group
Com. group
Design of JTEDs
Juv.&trash
Juv.&trash


Figure 1. Mean escapement rate, Thailand.
Figure 2. Mean escapement rate, Vietnam.
Experiment on types JTEDs in Philippines
Experiment on type of JTEDs in Malaysia
100
)
) 100
%
%
(
(
80
t
e
80
t
e
a
a
60
t
R
60
t
R
n
en
e
40
40
em
m
e
p
20
a
20
scap
c
E
0
Es
0
R S1
R S2
R S3
R ec .1
Semi.1
R S1.2
R S2
Com. group
Design of JTEDs
Design of JTEDs
Com. group
Juv.&trash
Juv.&trash

Figure 3. Mean escapement rate, Philippines.
Figure 4. Mean escapement rate, Malaysia.

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ICES WGFTFB REPORT 2008
Experiment on type of JTEDss in Brunei
Experiment on type of JTEDs in Indonesia
) 100
%
)
(
100
%
t
e
80
a
e (
80
R
at
60
nt
e
t
R
60
40
m
en
40
pe
20
a
em
c
p
s
20
0
E
sca
0
R S1
R S2
R S3
Semi.1
R ec .1
E
R S4
Semi.4
R ec.4
Design of JTEDs
Com. group
Design of JTEDs
Com. group
Juv.&trash
Juv.&trash

Figure 5. Mean escapement rate, Brunei.
Figure 6. Mean escapement rate, Indonesia.
EXperiment on type of JTEDs in Myanmar
30

)
e
120
%
at
25
t
r
100
t
e (
a
em
20
80
t
R
n
15
60
e
f
escap
m
40
t

o
e
10
en
20
5
scap
i
f
f
er
0
D
E
RS 1
RS 2
RS 3
S emi.1
Rec.1
0
RS1
RS1.2
RS2
RS3
Rec.4
Semi.1
Design of JTEDs
Com. group
Designs of JTEDs
Juv.&trash

Figure 7. Mean escapement rate, Myanmar.
Figure 8. Escapement rates among various devices.
The rate of escapement calculated by weight of escaped animals from different type
of JTEDs and different size of grid interval, the appropriate device should release as
much as possible the juvenile and trash fish while reduce the escapement of the target
catch. The results show that the value between both groups ranged from 13.78 to
61%. The highest one was obtained by using the rigid sorting grid type with 2 and 1.2
cm grid intervals while the lowest values were observed by using the rigid sorting
grid with 3 cm grid interval, the rectangular shaped window and the semicurved
window type with 1 cm grid interval (Figure 8). Based on this study, it can be con
cluded that the better performance on type and design of JTEDs was the rigid sorting
grid with 2 and 1.2 cm. grid intervals. However, others factors and conditions also
have to be considered in recommending this type and designs of JTEDs to the fisher
men.

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ICES WGFTFB REPORT 2008
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Table1. Comparison of the escapement rate between juveniles and commercial target groups each
superscripted number on the first raw indicate type of device used as denoted below.
RS12 RS1.23 RS24 RS35 Rec16 Semi17
Escapement rate of juvenile (%)
56.69
71
77
74.31
68.52
61.09
Escapement rate of commercial group (%)
9.72
11
16
50.33
46.75
47.31
Different value of escapement rate between
46.97
60
61
23.98
21.77
13.78
juvenile and commercial target catch
In percentage of different value of
20.64
26.37
26.80
10.54
9.57
6.06
escapement rate between juvenile and
commercial target catch

3 ) Selectivity by Rigid Sorting Grid JTEDs
Based on escapement rate of the juvenile and commercial/target catch groups includ
ing fish, shrimp and squids, the Rigid Sorting Grid with grid intervals of 2, 1.2 and 1
cm performs distinctively better than other types (Figure 8). The probability on size
of the catch which could escape at each grid interval is compared by the observed
and estimated selection curves. Due to Leiognathus equarus was found in all experi
ment sets the fraction retained for Leiognathus equarus is plotted against the total
length in the selection curve for the Rigid Sorting Grid with 1, 2 and 3 cm grid inter
vals. The results show that the L50% of those designs are 6.75 cm, 12.5 cm and 13.2
cm, the L75% are 7.79 cm, 15.01 cm and 16.40 cm respectively (Figures 9­11).
RS1
RS2
1
1
ed
d
0.8
0.8
a
i
n
et 0.6
e
t
a
i
ne
0.6
r
r
n 0.4
i
o
0.4
0.2
r
act
a
c
t
i
on
0.2
F
Fr
0
0
1
2
3
4
5
6
7
8
9
10
1 2 3 4 5 6 7 8 9 1011 12 1314 15 1617 18 1920
Length (cm)
Length (cm)
Observed selection
Estimated selection
Observed selection
Estimated selection


Figure 9. Selection curve by Rigid Sorting8
Figure 10. Selection curve by Rigid Sorting9

2 Rigid Sorting Grid with 1 cm grid interval
3 Rigid Sorting Grid with 1.2 cm grid interval
4 Rigid Sorting Grid with 2 cm grid interval
5 Rigid Sorting Grid with 3 cm grid interval
6 Rectangular shaped window with 1 cm grid interval
7 Semi-curved window with 1 cm grid interval
8 Sorting grid with 1cm
9 Sorting grid with 2cm

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ICES WGFTFB REPORT 2008
RS3
1
d 0.8
e
t
a
i
ne
0.6
0.4
a
c
t
i
on r
0.2
Fr
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14
Length (cm)
Observed selection
Estimated selection


Figure 11. Selection curve by Rigid Sorting.
The mean value of the fish size able to escape from the Rigid Sorting Grid JTEDs with
1, 2 and 3 cm grid interval is 5.36, 7.9 and 14.73 cm respectively. The mean value of
total fish length increases with increasing size of grid interval. However, as this re
gion is located in the tropical zone with high species diversity, (Sparre P. et al., 1989),
the grid interval of JTEDs should be well designed suitable for the average size of
target fish in each country.
Conclusions and recommendations
Based on the results of this experiment, Rigid Sorting Grid JTEDs with 1.2 and 2 cm
grid interval has better performance in maximizing the escapement rate of the juve
nile while minimizing the escapement rate of the commercial or target catch. The size
of fish which escaped from the devices depends on the size of the grid interval. In
this tropical region with high species diversity the fishermen are used to fish multi
target species with varying commercial size. Considering those factors it's compli
cated in selecting the best size of the grid interval.
The experiment was carried out in many countries to demonstrate and introduce this
device in the region. Although suitable design and size of the grid interval are re
commenced to continuing modification should be considered with relevance up to
date fishery information in each country. More importantly, fishers should be in
formed and make to understand the experimental results, and encourage them to
change their attitude for improved fishing operation. With achieved level of selectiv
ity the fishers can benefit from the sustainable marine resources.
References
Chokesanguan, B., Ananpongsuk, S., Siriraksophon, S., and Podapol, L. 2004. Study on Juve
nile and Trash Excluder Devices in Thailand, SEAFDEC/Training Department, pp. 1­18.
Chokesanguan, B., Ananpongsuk, S., Siriraksophon, S., and Abdul I. Hamid, 2004. Study on
Juvenile and Trash Excluder Devices in Brunei Darussalum, SEAFDEC/Training Depart
ment, pp. 1­15.
Chokesanguan, B., Ananpongsuk, S., Siriraksophon, S. Wanchana, W., and Long, N. 2004.
Study on Juvenile and Trash Excluder Devices in Vietnam. SEAFDEC/Training Depart
ment, pp. 1­20.
Chokesanguan, B., Ananpongsuk, S., Siriraksophon, S., and Rosidi, R. 2004. Study on Juvenile
and Trash Excluder Devices in Malaysia, SEAFDEC/Training Department, pp. 1­31.
Chokesanguan, B., Ananpongsuk, S., Chanrachakij, I., Manajit, N., and Tumpubolon, G. 2004.
Study on Juvenile and Trash Excluder Devices in Indonesia. SEAFDEC/Training Depart
ment, pp. 1­18.
Chokesanguan, B., Ananpongsuk, S., Siriraksophon, S., and Dickson, J. 2004. Study on Juvenile
and Trash Excluder Devices in the Philippines. SEAFDEC/Training Department, pp. 1­12.

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Jones, R. 1976. Mesh regulation in the demersal fisheries of the South China Sea areas, Manila,
South China Sea Fisheries Development and Coordinating Program. SCS/76/WP/34:75 p.
Kimura, D.K. 1977. Logistic model for estimating selection ogives from catches of codend
whose ogives overlap, J. Cons. CIEM, 38(1):116­9.
Pope, J.A., et al. 1975. Manual of methods for fish stock assessment. Pt3. Selectivity of fishing
gear, FAO Fish. Tech. Pap., (41) Rev.1:65 p.
Mastawee, P., and Theparoonrat, Y. 2002. Trawl Net Mesh Selectivity for Lizardfish (Saurida
elongate) and Blackspotted Trevelly (Caranx leptolepis) Using Square and Diamond Mesh
Codend, Thai Fisheries Gazette, Vol.55.P.457­465.
Sparre, P., Ursin, E., and Venema, S.C. 1989. Introduction to tropical fish stock assessment, Part
1Manual, FAO Fish. Tech., 306:1, 337p.
Tokai T, Omoto S., Satou, R., and Matuda, K. 1996. A method of determining selectivity curve
of separation grid. Fish. Res., 27:51­60.

Indonesia
Prof. Dr. Ir Ari Pubayanto, Faculty of Fisheries and Marine Sciences, Bogor Ag
ricultural University, Bogor
Brief background of the national (shrimp) trawl fisheries
1 ) Shrimp trawl fisheries were firstly introduced in Indonesia in 1970's by
foreign investment industry (PMA) and had improved increasingly.
2 ) By the year of 1980, the government banned the use of trawl through resi
dential Decree No. 39/1980.
3 ) Through Presidential Decree No. 85/1982 concerning with operational of
shrimp trawler, the government of Indonesia has permitted the use of
shrimp trawl to operate in certain area, limit in amount of fleets and obli
gated to install a TED on the net.
Fleet number and distribution
1 ) The shrimp trawl is licensed to operate in 1300 East to eastern around the
adjacent waters of Kei, Tanimbar and Aru Island.
2 ) Some kinds of fishing gears (trawl like, but not trawls) are licensed to be
operated by the small scale fishermen in all over Indonesia waters.
3 ) Fleet number of shrimp trawlers (large scale) that have been licensed ap
proximately 200 units.
4 ) The small scale shrimp trawlers that have been licensed (by local govern
ment) are approximately 50,980 units. Commonly, they are named locally
by fishermen themselves as shown in the Table 1.

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Table 1 Types of trawl that are existing in Indonesia.

Name
No
Name
No
1
Pukek Osoh (Padang)
12
Krakat (Java Sea)
2
Pukat Ular (Sibolga)
13
Mini Beam Trawl (Java Sea)
3
Pukat Apolo (Mallacca strait)
14
Arad (Java Sea)
4
Pukat laying (Mallacca strait)
15
Arad berpalang/ berpapan (Java Sea)
5
Dogol (Mallacca strait)
16
Mini Trawl (Maccassar Strait)
6
Dogol berpalang/berpapan (Java Sea)
17
Andu (Java Sea/ DKI)
7
Cantrang berpalang/ berpapan
18
Lampara (Seram, Tomini, Sulawesi)
8
Lampara dasar berpapan/ berpalang (Java
19
Lampara dasar (Sibolga, Belawan,
Sea)
Makassar)
9
Cotok (Java Sea)
20
Jaring WCW (Java Sea)
10
Garuk kerang (Java Sea)
21
Katrol/ Rengreng (Makassar Strait)
11
Payang Alit (Java Sea/ East Java)
22
Paddenreng (Makassar Strait)
Goals/objectives of project implementation in Indonesia
1 ) Referring to nowadays fishermen's are willing to review the possibility of
reoperating trawl in Indonesia waters;
2 ) It is necessary to assess the socioeconomic and environmental impact of
the fisheries to the fishermen;
3 ) Through the FAOGEF Project, the government of Indonesia expect to get
some goals/objectives such as:
a ) To assess the existing condition of fish resources and their habitat
b ) To assess the existing types of fishing gears used for catching the
demersal fisheries/shrimp
c ) Redesign the existing BRDs to make it appropriate with the Indonesian
waters and type of fishing gears (trawls)
d ) To review the existing legislation for regulating the shrimp trawl man
agement in Indonesia
Strategies and activities undertaken since the start of implementation
1 ) Conducting regular meetings with the stakeholders (industries sector, sci
entists, NGO/ fishermen) to formulate the grand strategies for solving the
shrimp trawl problem in Indonesia waters
2 ) Defining the national steering committee of the project to work more
closely, hand in hand each other
3 ) Involving the regional/ international issues concerning the shrimp trawl
matters
4 ) Preparing the national work plans for the shrimp trawl issues, that consist
of:
a ) Problem identification concerning bycatch
b ) Stakeholder meetings
c ) Field surveys

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d ) Base line study of BRD
e ) Development / adaptation of BRD technologies (optimisation and ex
perimental trial)
f ) Meeting, workshop
g ) Field demonstration of new technologies
h ) Research and engineering the Appropriate BRDs
i ) Reviewing and enhancing Bycatch Reduction and Change Manage
ment of Trawl Fisheries through Comprehensive Regulations
j ) Introduction of appropriate BRDs technology to shrimp fishing fleets
k ) Dissemination of result
l ) Legalizing for BRD standardization
m ) Project evaluation
Members of the National Steering Committee
HPPI: Shrimp Fishing Industry Association
ASPINTU: NonTuna Industry Association
BRPL: Marine Fisheries Research Body
BBPPI: Fishing Technology Development Center
IPB: Bogor Agriculture Institute
STP: Jakarta Fisheries Institute
Table 2. Result and major technical achievements.
No
Activity/ Types of BRDs tested
Time
Devices tested
1
Introduction (demonstration and training on
26 August, ­ 6
1. TED: super shooter and
TED/JTED) in Sorong, Papua Province
September
bent pipe
2002
2. JTED: semicurve
window, rigid sorting grid
and rectangular windows
2
Introduction (demonstration and training on
20­25 October,
1. TED: super shooter,
TED/JTED) in Ambon, Maluku Province
2003
Bent Pipe,
2. JTED: Semi Curve
Window, Rectangular
Shape window and Rigid
Sorting Grid
3
Introduction (demonstration and training on
4­9 October,
JTEDs:
TED/JTED) in Sibolga, North Sumatra
2004
Rectangular shape,
Province
Circular shape,
Rigid sorting grid and
Semi ­ curve Rigid sorting
grid
(1 cm, 2.5 cm, 4 cm)

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No
Activity/ Types of BRDs tested
Time
Devices tested
4
Introduction (demonstration and training on
13­21 June,
1. TEDs:
TED/JTED) in Tual, Souteast Maluku Province
2004
Super Shooter, Bent Pipe
and
TTFD (Thai Turtle Free
Device)
2. JTEDs:
Rigid Sorting Grid,
Rectangular Shape
Window and
Semi Curve Window
5
Symposium On Present Status of Trawl In
25­27 April,
Base line study of BRD
Indonesian Waters in Jakarta
2005
6
Introduction (demonstration and training on
28 November,
1. TED: Bent pipe
TED/JTED) in Merauke, Papua Province
4 December,
2. JTED: Semicurve rigid
2005
sorting grid (1 cm; 1,5 cm,
2 cm and 3 cm)
7
Dissemination of Turtle Excluder Devices
1 March, 2006
Dissemination
(TEDs) Installation on Shrimp Trawl Net in
Indonesia "Promoting The Awareness of
Commercial Shrimp Trawl Fisheries towards
The Sustainability Fisheries"
8
Introduction of Turtle Excluder Devices/Ted
12­16
TED Super Shooter Flat
(Super Shooter) on Small Scale Ecofriendly
November
Bottom type (MV. Madina,
Trawl Net in Makassar Strait Areas
2006
30 GT).
TED Super Shooter Round
Bottom type (MV. Karya
Nelayan 2).
9
Preliminary Review of Legislative and
Desember
Badia Sibuea
Regulatory Frame Work in Relation to
2006
Melda Kamil Ariadno
Bycatch Reduction in The Shrimp Trawl
Fisheries in Indonesia
Table 3. Result and major technical achievements.
1
Translating Book Of "A Guide To Bycatch
April ­ June,
Eni Sutopo
Reduction In Tropical Shrimp Trawl Fisheries"
2007
By Mr. Steve Eayrs
2
Reviewing And Enhancing Bycatch Reduction
2007
FPIK IPB
And Change Management Of Trawl Fisheries
FH Univ. Indonesia
In Indonesia Through Comprehensive
(Prof. Daniel Monintja,
Regulations
team leader)
3
Research and Engineering the Appropriate
2007
BBPPI Semarang
BRD for Ecoriendly Trawl in Indonesia
FPIK IPB
(Prof. Ari Purbayanto,
team leader)

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ICES WGFTFB REPORT 2008
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4
Overall Expose "What and What Next":
Jakarta, 18­19

Dissemination of Bycatch Reduction Devices
March, 2008
(BRDs) and Change of Management for Trawl
Fisheries in Indonesia
CURRENT STATUS OF SHRIMP TRAWL FISHERIES IN INDONESIA
1 ) The increased of fuel price worldwide (also in Indonesia), has become a
great challenges to survive for the industry;
2 ) Some measures are taken by the industry, i.e.:
a ) increase the effectiveness of technical trawl performance during the
operation (use the smaller twine/ rope of net, enlarge the mesh size, etc
to reduce the net resistance);
b ) increase the effectiveness of financial performance (maintain the valu
able bycatch/ not discard them anymore, etc);
3 ) In the other side, the abovementioned situation, positively bring a good
atmosphere to have a closer dialogue between Industry and Government;
4 ) Therefore, the idea of comprehensively change management for trawl fish
eries (as will be regulated through The Presidential or Ministerial Decree?;
open/ close season, open/ close area, the use of TED/ BRDs, etc) are wel
comed by the industry;
5 ) The idea to open the trawl license in right manner/ management (which
was banned, especially for small scale fisheries, but in fact it was widely
operated by fishermen) are welcomed;
6 ) The draft of new regulation introducing change manner/ management for
trawl fisheries in Indonesia (comprehensively Presidential Decree on trawl
management in Indonesian waters; open/ close season, open/ close area,
the use of TED/ BRDs, etc) had been finished by the completion of Review
ing & Enhancing Project on 14 October 2007 to use the tested TEDs/ BRDs;
7 ) Further action are needed to finalize the implementation of the compre
hensively change management for trawl regulation in Indonesia; socializa
tion/ public hearing, implement the idea in a pilot project area, etc.
CONCLUSIONS
Mostly, goals of the project (as indicated in the achievable indicators) will be able to
be achieved by the completion of the ongoing project BRDs Research & Engineer
ing), are:
1 ) By June 2008, a draft of new regulation to use the tested TEDs/ BRDs and
change of management had been finished
2 ) (The draft of The Presidential Decree has been finished, 14 October, 2007)
3 ) Trial level, at least 20% reduction in discard in trials while maintaining the
level of shrimp catch in 12 participating countries
4 ) (13.36%, during the fishing trial for BRDs Research and Engineering Pro
ject)
5 ) Socioeconomic level, maintained level of net income of fishermen and in
dustry after introducing the selected BRDs as impact of the socioeconomic
6 ) (No progress yet: Pilot project for ecofriendly trawl management in Indo
nesia was pending)

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7 ) On theground impact level, 50% of the vessels of industrial trawl shrimp
fishery will introduce tested BRDs by June 2008 in Indonesia (onprocess
strategy: Renew the existing DG of Fisheries Decree on BRDs Construction
as resulted by the Research & Engineering The Appropriate BRDs project)
8 ) At least 15% of the vessels of artisanal trawl fishery will introduce tested
BRDs by June 2008 (No progress yet: Pilot Project for ecofriendly trawl
management in Indonesiapending)
9 ) Research and Engineering the Appropriate BRDs in the Indonesian Waters
will be organized
10 ) (Has been conducted: fishing trial 29 November ­ 9 December, 2007)
11 ) Indonesia will have adopted the techniques developed and transferred by
other countries at beginning of 2007 (comparative study to Australia
pending)
The consciousness on having a responsible trawl management in Indonesia waters
has increased, as indicated during the latest workshop on trawl fisheries in Jakarta
(Overall expose "what and what next":..., i.e.:
1 ) The draft of Presidential Decree on Trawl Management in Indonesia (pre
sented by the Reviewing and Enhancing... Consultant) was agreed with
minor suggestion to be taken for further action (legalizing);
2 ) The participants agreed with all management measures as drafted in the
new regulatory for managing trawl fisheries in Indonesia;
3 ) The participants agreed to enlarge mesh size of codend become > 50mm
(for shrimp) and > 120mm (for fish).
4 ) The participants agreed to obligate to install BRDs either for shrimp
(TEDs) or fish (square mesh?).
RecommendationS (for REBYC Phase II)
1 ) A mechanism of information sharing between participating countries
should have been prepared before end of project, either the project will be
continued by the 2nd phase or not;
2 ) Before end of the project (June 2008), a new FAOGEF Project commitment
to follow up the project should be arranged. Since, each country seems to
be not able to get 100% (in average less than 50%?) of achievable target as
discussed at our last meeting in Philippine;
3 ) The new project should involve wider participating countries among each
region (Asian, Western Africa, Gulf Region, Latin America and Caribbean).
For instance: Malaysia, Singapore, Brunei, Vietnam, Laos, and other coun
tries in Southeast Asia region. Since, fisheries resources are sometimes also
utilized by some other countries (particularly in EEZ of each country, on
which haven't been fully utilized by the shore country) also because of
fishes are migratory species;
4 ) A wider stake holder (private sectors, researchers/ academicians, etc) also
should be involved in the new project;
5 ) The new project should cover issues on the improvement of fishers' con
sciousness on fisheries resources, not only turtle conservation.

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Iran
A. Mojahedi, Iranian Fisheries Organisation, Deputy for Fishing and Fishing
Harbours, Tehran, Iran.
Abstract
National Research activities on Bycatch reduction started in 1992 at Persian Gulf
Fisheries Research Center (Boushehr) and First BRD fabricated in the same year. Af
ter these initial measures, square mesh efficiency in Shrimp trawl net was investi
gated and 100 mm Square mesh window, showed improved results in excluding
small fishes. Two years after obligatory use of SMW in shrimp trawl nets and achiev
ing not ideal results, Iran Fisheries Organization in cooperation with FAO, launched
new round of experiments in 1997. Different types of BRDs have been experimented
during these trials, such as: RES, NAFTED, Fish eye and cone. Initial outcomes
showed that NAFTED is efficient for excluding large aquatics. Broad range studies
performed during years 2000­2001, on bar devices (NAFTED & Grid) and SMW
comparison and results pointed out that Grid Type (NORDMOR Grid) is the most
efficient one comparing with other devices. Regarding achieving results, during 2006,
100 Grid 8mm devices, have been fabricated and applied for Industrial trawlers.
Regarding this fact that, more than 90% of shrimp capture, harvested by artisanal
fishing vessels fleet and graduation adjustment plan for Industrial trawlers which
practically will reduce Industrial shrimp trawler numbers, therefore it is necessary to
experiment and promote BRDs on artisanal vessels. Then the aim of the project based
on excluding juvenile and small fish. All measures in project framework planned to
achieve this goal. Net modification is the first option for excluding juvenile and small
fishes, and further options could be most effective device which will be selected
through experiments and advices we receive from international consultants.
Grid 80 Installation on Industrial Trawlers
Sessions and Decisions:
In total, 6 sessions have been held during this stage of project progress and different
decisions have been taken.
· Projects secretary session held on Saturday, April14, 2007 to make decision
for assembling steering committee and determine operational measures.
Mr. Ali Mojahedi, Mr. Hussein Ostadmohammadi and Mr. Shahram Safi
yary, attended this session and following decisions resulted:
i )
Steering committee members determined and it is decided those com
mittee sessions to be formed along with project progress.
ii )
Technical committee members determined to hold a session and decide
on project performance aspects and report outcomes to steering commit
tee for approval
iii ) Preparing a brief report on Project Background and achievements in
pervious stages to Steering committee members
iv ) Setting up Time and Cost tables
· Two Technical Committee sessions (comprises experts from IFO and Local fisher
ies offices namely Boushehr, Hormozgan) held on April 23 and May 27, 2007 to
make decision on Operation.

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Technical aspects with following outcomes:
· Performing trials by artisanal shrimp trawling vessels in Hormozgan and
Boushehr provinces
· Grid 80 Installation training in active shrimp trawlers and surveillance
during shrimp harvest season
· Following devices and modifications recommended to steering committee
for trial completion:
Trawl net construction modification
· JTED
· Applying proper Grid according to artisanal vessels
· Trawl nets
· Net modification through bottom chain
· Applying Fish eye
Regarding this fact that net construction diversity is too much in two mentioned
provinces artisanal vessels, most common net and Dhows, decided to report to the
steering committee for further decisions.
· Artisanal vessels with engine power between 200­300 horse powers se
lected as most suitable group for trial performance.
· 3 amended nets, to be fabricated, based on technical committee proposed
plan
· 5 JTEDs to be fabricated, for each province Juvenile and small fish deter
mined as main excluding target group.
· Three steering committee sessions, as the highest assembly for projects pro
gress decision making, have been held on 25 June.
· 2007, 16 October, 2007 and 30 January, 2008 in Tehran, Bandarabbas and
Qeshm Island respectively. following decisions have been finalized during
these sessions and communicated for implementation:
i )
Final selection of two Dhows which introduced by technical committee
ii )
Final selection of the province which trials should be performed in its
water
iii ) Review the results of Shrimp trial trawl accomplished by Ho mozgan
province Dhows (results review, outcomes analyzing and discussing on
Constraints and problems)
iv ) Regarding high discard level by fishing trawlers , it is decided that some
projects capacities exploit for this issue , based on agreement with FAO
v )
Deciding on workshop holding time, International consultant capabili
ties and selection, after workshop trials
3rd Steering Committee session
Performed Measures
During 6 months from July to December 2007, different measures have been taken in
different fields, but the main task was BRD trial by artisanal shrimp trawlers in Hor
mozgan waters. Below all measures are listed:

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· Holding three training sessions for fishermen in Hormozgan and Boushehr
provinces.
· Producing Extensional program to broadcast from local media.
· Distribution and Installation of Grid 80 device on 11 Industrial trawl ves
sels. These devices fabricated in 2006 and distributed for shrimp harvest
season in Hormozgan and Boushehr. A team consists of 6 experts during
shrimp harvest season were onboard for Installation, Training and super
vision purposes.
· BRD fabrication and Net making ­ 6 trawl nets (3 for Boushehr vessels and
3 for Hormozgan vessels) and 10 JTEDs (5 for Hormozgan vessels and 5
for Boushehr vessels). It is notable that all primary works had been done to
perform experiments in Boushehr, but due to delay in fund release ap
proval for vessels contract, the trials program shifted to Hormozgan prov
ince vessels. Fabricated devices could be utilized for shrimp harvest season
2008.
· Purchasing essential needs for project progress such as: Laptop computers,
Scales, Biometry devices, personal needs for onboard personnel.
· Producing a documentary movie from all trials step in English.
· Producing an Extensional movie to introduce BRDs and to increase rate of
acceptance in Farsi language.
· Printing Promotional items specifically: Posters, Banners, and Stands.
· for BRD promotion in fishing harbours and fishing vessels.
· Forming teams consist of experienced experts to execute trials properly.
· Holding frequent sessions for experts for experiments superior perform
ance. Most of mentioned steps have been done for trial execution by artisanal
shrimp trawlers.
Experiment implementation on Artisanal shrimp trawlers in Hormozgan province
waters in a 29 days period. Regarding importance of this project step, it is described
separately. This experiment, has been performed for the purpose of different Bycatch
Reduction Devices comparison, in Artisanal trawlers, within Hormozgan province
fishing grounds (contains: Sirak, Kuhestak, Dar Sorkh, Aab Shirin Kon, Keshtie
Sukhte, Tula) during 29 days shrimp harvest season (from 8 October, till 13 Novem
ber, 2007) by two trial and blank vessels which harvested simultaneously.
Two different types of devices namely; JTED (for juvenile fish reduction) and Modi
fied ground gear (from horizontal to parallel for seabed destruction reduction) exam
ined based on a pre determined schedule. Data related to each harvest operation, has
been recorded separately in specific forms contain some information e.g. vessel
speed, harvesting time, longitude and latitude, fishing ground information, Sea con
ditions, discard level, juvenile fish level lower than LM50(Length at which 50 per
cents of the individuals fish, matured), large fish harvest amount, shrimp harvest
rate, etc. Results obtained from 91 times fishing, showed that by applying JTED in 44
times fishing turns, small shrimp weight and large shrimp weight have been reduced
16.5% and 43%, respectively. However commercial fish species have been increased
by 0.5% and discard reduced by 38.6%.
Applying JTED equipped with guiding panel 28 times fishing turns, small size
shrimp and large size shrimp reduced by 31% and 18.5% respectively. However
commercial fish species increased by 6.7% and discard rate reduced by 45%.

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Applying parallel chain ground gear in 15 fishing turns, demonstrated; small size and
large size shrimp reduction, 38.9 and 20.7%, respectively. Commercial fish species
and discard amount also decreased by 26% and 3.3%, respectively.
Consequently, shrimp reduction in both JTED with guiding panel and without guid
ing panel, observed. But the shrimp reduction amount in JTED with guiding panel is
lower; In the meantime Bycatch reduction percentage in this device is higher. There
fore JTED with guiding panel is more efficient.
As we observe in parallel chain ground gear results; shrimp reduction amount is
similar to other experimented devices and Bycatch reduction rate is extremely low
(3.3%) and could be considered sufficient only for commercial fish species.
Ultimately it is concluded that; comparing these 3 devices shows that; according pro
ject objectives, JTED with guiding panel is more sufficient in comparison with 2 other
devices.
Vessels Technical specification:
Two dhows (Artisanal vessel) used in trials with below specification:
Rostami (3/9749) ­ Fiberglass
Length: 21 Meters
Width: 6 Meters
Engine Power : 300 Horsepower
Yaar(3/7304) ­ Wooden
Length: 19.2 Meters
Width : 6.8 Meters
Engine Power : 320 Horsepower
Navigation system for both vessels is GPS ­ Wireless set
Fishing Gear Technical specification:
Otter Board: wooden with metal frame Weight : 85 Kg, Dimensions: 180
* 90
Ground Gear : Chain No.8 , Weight : 75 Kg , Length : 53 Meters
Float : EVA , No.10 , Quantity : 21
Net:
Mesh size in main body : 45 210D/24Ply/45mm STR/100MD/200y
Mesh size in Cod end : 20 210D/30Ply/20mm STR/100MD/100y
Net material : Poly amide
Treatments
After Technical committee assembly and holding expert sessions in Hormozgan
province, it was decided; following treatments to be done: JTED;(aiming juvenile fish
reduction) 2 situation ; with and without Guiding panel
Ground Gear Modification from horizontal to parallel position (aiming avoiding sea
bed destruction and stingray catch reduction)
JTED Device specification
Material: Metal frame and rope net
Weight: 13.5 Kg
4 Buoys, No.10 EVA
Dimension: 3 sections each : 40*50 cm
Grid bar spacing : 4 cm

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ICES WGFTFB REPORT 2008
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Grid angle : 45º
Grid bindings : 40 cm
Angle fitting by chain
Modified Chain specification
Weight: 75 Kg
Quantity: 131
Chain height: 40 cm
Chain spacing: 28 cm
Links number for each chain: 16 & 17 links
Trial fishing Implementation
BRD test project for shrimp Artisanal trawlers in Hormozgan province started Octo
ber 8, 2007 and completed; November 13, 2007.(totally 29 working days onboard) 91
harvests, each one took long 2 hours, by 2 vessels simultaneously, being parallel,
have been completed. One vessel as blank (ordinary net), another one as trial
equipped with BRD harvested, at the same time. Catch statistics, recorded precisely
in particular forms. Three treatments were done, in this trial fishing period which in
treatment 1 to 3; with 44, 28 and 15 times harvesting, respectively.
Table 1. Treatment 1 (Traditional Net + JTED). Number of Tows= 44.
Large Shrimp kg
Small Shrimp kg
Commercial Fish kg
Discards kg
Control
Trial
Control
Trial
Control
Trial
Control
Trial
1159
657
322
268
353
354
8564
5240
43% reduction
16.5% reduction
0.5% increase
38.6% redcution
Table 2. Treatment 2 (Traditional net +JTED with cover). Number of Tows = 28.
Large Shrimp kg
Small Shrimp kg
Commercial Fish kg
Discards kg
Control
Trial
Control
Trial
Control
Trial
Control
Trial
156.6
127.6
124.2
85.4
132.5
141.5
2218.5
1217.6
18.5% reduction
31% reduction
6.7% increase
45% reduction
Table 3. Treatment 3 (Traditional net +parallel chain). Number of Tows = 15.
Large Shrimp kg
Small Shrimp kg
Commercial Fish kg
Discards kg
Control
Trial
Control
Trial
Control
Trial
Control
Trial
939
744
208.5
127
77.5
57.2
2218.5
1217.6
20.7% reduction
38.9% reduction
26% reduction
3.3% reduction
Funds and Costs
The total fund for project is 375000 USD, which, roughly 84423.86 USD of this amount
was spent till end of 2007. Due to some problems have occurred, some costs have
been cancelled and replaced with other items. Namely Purchasing Vehicles men
tioned in (40000USD) and Dhow leasing, both funds will be used in Fish trawling
Workshop regarding a mutual agreement between National coordinator and Mr.
Fogelgren. According to our commitments for performing rest of project phases, fol
lowing task has been remained: Almost 12000 USD for Documentary Movie

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Almost 6000USD for Statistics program (Regarding completed BidOffer) Almost
10000USD for Farsi version of Bycatch reduction manual (translation and print) ­ Bid
process is underway. Almost 6500USD for Kids Drawing book ­ Bid process is un
derway for Costs of Trawl Management Regional Workshop, Trials and International
consultants are roughly 70000USD as mentioned in TOR.
Results and Outcomes
Results obtained from 91 times fishing, showed that by applying JTED in 44 times
fishing turns, small shrimp weight and large shrimp weight have been reduced 16.5%
and 43%, respectively. However commercial fish species have been increased by 0.5%
and discard reduced by 38.6%. Applying JTED equipped with guiding panel 28 times
fishing turns, small size shrimp and large size shrimp reduced by 31% and 18.5% re
spectively. However commercial fish species increased by 6.7% and discard rate re
duced by 45%. Applying parallel chain groundgears in 15 fishing turns,
demonstrated; small size and large size shrimp reduction, 38.9 and 20.7%, respec
tively. Commercial fish species and discard amount also decreased by 26% and 3.3%,
respectively. Shrimp reduction in both JTED with guiding panel and without guiding
panel, observed. But the shrimp reduction amount in JTED with guiding panel is
lower; In the meantime Bycatch reduction percentage in this device is higher. There
fore JTED with guiding panel is more efficient. As we observe in parallel chain
ground gear results; shrimp reduction amount is similar to other experimented de
vices and Bycatch reduction rate is extremely low (3.3%) and could be considered
sufficient only for commercial fish species. Ultimately it is concluded that; comparing
these 3 devices shows that; according project objectives, JTED with guiding panel is
more sufficient in comparison with 2 other devices.
Cuba
Luis Font Chávez, Fishery Ministry, Havana, Cuba, jfont@cip.telemar.cu
Abstract
Constructive characteristics of trawl nets used in tropical shrimp fisheries, present a
marked negative effect on benthic populations and bottom species, constituting a
threat for conservation of biological diversity and marine environment. Nevertheless
and taking into account that the catch of this resource represents an important eco
nomic and social source, it is necessary to promote the use of lower impact catch
technologies and that their introduction in the fishery be technical and economically
feasible. Results reached up to present in the project have been aimed to the design,
construction and test at experimental and commercial level, in Santa Cruz del Sur
Fishing Enterprise, of a less harmful fishing technology to environment, being veri
fied important advantages as: to allow an escape of near 25% of bycatch, thus reduc
ing the negative effect on fish populations and specially juvenile stages of Lane
snapper (Lutjanus synagris) and also increasing the fishing gear selectivity to the catch
of Pink shrimp (Farfantepenaeus notialis), with no detriment of the present observed
levels and consequently an increase in the catch exportable value. At the same time,
regulatory measures on the fishery have been dictated which substantially contribute
to the protection of shrimp populations and species composing bycatch. Other fore
seen results are related to the reduction of net constructive costs and fuel consump
tion. Project execution has been characterized by the active participation of managers,
technical personnel of the Enterprise, as well as captains and fishermen of shrimp
vessels, who have contributed with valuable experiences and practical execution in

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ICES WGFTFB REPORT 2008
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the project development by participating in cruises, conferences, workshops, and ad
vanced qualifying courses for the personnel dedicated to net construction. The new
fishing system will be introduced in Santa Cruz del Sur Fishing Enterprise at the end
of ban in the 2008­2009 seasons.
RESULTS
WORK AREA
Investigation was conducted in Santa Cruz del Sur Industrial Fishing Enterprise op
eration area, Province of Camagüey, located in Cuba's southeastern zone.
Design, construction and test of net prototypes
The new design of shrimp twin net used is the denominated Prototype E3 (10.4/10.0
m), with a fish escape device fish eye type. Design of net Prototype E3 is the result
of previous development of 6 experimental cruises with 154 hauls, which allowed to
improve both prototypes (E1 and E2) initially used. Traditional net is the denomi
nated shrimp net 9.0/9.8 m, currently employed in vessels operating in the Enterprise
fishing zone. In Table 1 the main characteristics and calculated technical parameters
are presented, that define the hydrodynamics quality of both fishing gears.
Table 1. Characteristics and technical parameters of the Traditional and E3 net.
Parameter
Traditional Net
E3 Net
Upper rope length, m
9.0
10.4
2
Area of net mesh part, m .
155.0
129.6
2
Area of net mouth, m
9.8
10.0
Horizontal opening, m
6, 3
7.3
Vertical opening, m
1,9
1,6
Net weight without codend, kg
7,4
5.9
Resistance to trawl, Newton
1609.4
1415.3

These modifications mainly influence in the increase of horizontal opening and de
crease of vertical's, contributing to the reduction of fish catch of the system, taking
into account the distribution habits in the water column of the species that compose
bycatch. On the other hand, differences in mesh surface area, net weight and hydro
dynamics resistance, directly influence in a lower effort of main engine and a slight
reduction in materials and fuel consumption.
A fish escape device was added to the net, constructed of stainless steel bars of 8 mm
diameter and consists in an ellipseshaped ring with a larger diameter of 50 cm and a
smaller one of 25 cm, with a 50 cm total length, which is fixed to a piece of mesh
added between the net body and the codend and in the upper central line of the net
To verify the fishing and economic efficiency of the new fishing system under com
mercial regime, 3 cruises were conducted, with a total of 99 hauls with an average
duration of 2½ hours, on board Vessels FC24 and Plástico 1, of 21 meters of overall
length and constructed of ferrocement and fibreglass respectively and equipped with
traditional nets in a side and Prototype nets E3 with Fisheye type escape device in
the other. Nets were alternated in their location, considering operational characteris
tics of trawls in the fishing zone, which generally make turns that increase the

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ICES WGFTFB REPORT 2008
trawled area by starboard side, which slightly influences in catch increase of nets lo
cated in this side of the vessel.
Effects of the new fishing system on shrimp catch
Catch and size composition
In the three commercial cruises performed, with a total of 99 hauls, catches obtained
by both fishing gears were similar, with slight increases in net E3, although statisti
cally no significant differences were observed among them. Nevertheless, the reten
tion of greater sizes in net under study resulted evident. Processing of the observed
size composition from measurement obtained in the 3 commercial cruises, with a to
tal of 8 580 individuals in the case of the experimental net and 8 473 in the traditional
one, indicated that sizes lower than 8.2 cm are retained in a greater extent in the lat
est, while for sizes higher than 8.7 cm the result is inverse. Mean values for the tradi
tional and modified net were of 8.6 cm and 8.8 cm respectively.
Economic assessment determined by the gear effect on shrimp catch
The increase of gear selectivity favourably influences the escape of small individuals,
which are likely to be caught later at a greater size. Additionally, if taken into account
the volumes of shrimp catch in both fishing systems, the economic result of the fish
ing operation is higher for the same operation level.
Calculated value of the catch is presented in Table 2, observed by type of fishing gear
in the three commercial cruises, evaluating the levels of catch by exportable category
to the current prices of the international market, (Exporter CARIBEX February/2008)
and applied to the marine shrimp export categories, for 1 ton of catch. Results indi
cate an increase of USD 343.35 by ton, according to the size composition retained by
each net.
Table 2. Catch value by type of net.
Categories Price/kg
USD
Traditional Net
E3 Net
Income/ton USD
Income/ton USD
100/120
4,65
1081,60
906,98
80/100
5,91
549,65
508,74
58/80
6,23
883,00
895,70
43/52
6,88
1193,55
1174,69
34/43
7,18
611,90
627,97
28/34
10,80
1430,24
1561,99
22/28
12,07
996,41
1218,00
13/21
15,80
931,81
1127,44
Total

7678.16
8021.51
Increase in catch value/ton
343.55
Incidence of the new fishing system on fish catches reduction
Bycatch of shrimp fishery in our country is constituted by a large amount of marine
organisms, in which fish predominate with values near to 75­80% of the total caught.
Levels of presence in catches depend on multiple factors, among which can be mainly
cited: fishing time, trawl depth, season of the year, geographic location, as well as

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ICES WGFTFB REPORT 2008
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those caused due to the design of the net used, deficiencies in calibration of trawl
doors, excess of weight in the footrope and trawl speed.
In Cuban fisheries, the bycatch/shrimp rate ranges between 3.2 and 6.3 values, being
likely to reach higher levels in hauls performed in areas where sponges, sea urchins
(Moyra sp) or jellyfish (Aurelia aurita) are abundant according to the life cycle of these
species.
Analysis of species composition by commercial and sampling cruises over the last
five years, for Ana Maria and Guacanayabo Gulfs, showed that there are 11 fish spe
cies representing near 90% of the catch and from them: Yellow fin mojarra (Gerres
spp).
Lane snapper (Lutjanus synagris), Mojarra (Diapterus sp), Atlantic bumper (Chlo
roscombrus chrysurus) and Tomtate grunt (Haemulon aerolineatum), integrates near
75%. The Ground croaker (Micropogonias sp), Searobin (Prionotus punctatus), Sand se
abass (Diplectrum formosum) and the Blackedge cuskeel (Lepophidium graëllsi), present
incidence levels in the order of 5 to 3%.
A noticeable variation in species compositions is observed from the beginning of the
90´s of last century, reported by several national authors. Such a variation is due,
among other factors, to overexploitation of bycatch components, mainly fish, by the
null selectivity of the shrimp fishing gear. This has determined that predominant
species at present catches, are of low commercial value and others like lane snapper,
sand sea bass and the blackedge cuskeel, are caught in juvenile stages and show a
considerable reduction in current catch volumes, regarding the above mentioned pe
riod.
Effect of the new system on fish catches
Results obtained in experimental cruises and corroborated in those conducted under
commercial fishing conditions, indicate a reduction near 25% of fish catches, includ
ing a 4.1% of lane snapper juveniles, thus decreasing the negative effect of the current
shrimp gear on the sustainability of fish resources in the fleet operation zone.
On the other hand, as previously indicated, fish escape by the use of escape device
contributes to the quality of shrimp caught, because the resource suffers a lower me
chanical damage taking into account that cleaner catches are obtained, being reduced,
additionally, time employed in catch processing on board the vessel.
Fishing management measures adopted:
Regulation measures, constitute a valuable tool for the protection of shrimp resources
and bycatch in general, especially those directed to the application of total closures
and by areas, diminishing of fleet capacity and the increase of the selectivity of the
fishing gear. In Cuba, in recent years the following resolutions have been established.
INCREASE OF TOTAL BAN PERIOD
Resolution 180/2003 July 15 October 15 3 months
Resolution 158/2004 July 15 November 15 4 months
Resolution 112/2005 July 15 November 30 4 ½ months
Resolution 155/2006 July 15 November 30 4 ½ months
(Resolution 078/2007 April 1st/07 February 1st /2008 10 months)
OTHER PROVISIONS ­ Resolutions 158/2004 and 155/2006.

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ICES WGFTFB REPORT 2008
PROTECTION OF NURSERY AREA
· Shrimp trawl prohibition to less than one nautical mile from coast.
LIMITATION OF FISHING EFFORT LEVEL
· Limitation of number of vessels allowed operating in the fishing zone to 50
units.
INCREASE IN NET SELECTIVITY
· Increase in mesh size of shrimp nets.
· Prohibition the use of a second codend and establishment the covering the
bottom half of the codend with a protecting net sheet.
RECRUITMENT PROTECTION
· Suspension of fishing in zones of high abundance of small size shrimps
and stages of molt (small and damaged shrimp) superior to 25%.
Present status of investigation
As a conclusion of the experimental phase and verification of results in commercial
cruises, it was arranged with the direction of Santa Cruz del Sur Fishing Enterprise to
rig 3 vessels with the new system, which would begin to operate at the end of current
ban (February, 2008). At present time, 2 vessels are operating with this fishing gear,
with results that corroborate those obtained in the experimental phase. The third ves
sel should begin to work next month of March, when the new gears are available.
These activities are aimed to gradually introduce the system and to acquire the prac
tical experience by the captains and crew.
On the other hand, Santa Cruz del Sur Fishing Enterprise and PESCACUBA Enter
prise Group is providing knowledge and support for the execution and conclusion of
the project, due to their active participation in the development and exchange of ex
periences with vessel captains, being also pointed out in addition, that personnel for
construction of new nets is available, who was qualified through theoreticalpractical
courses.
Introduction of the Net E3 with escape device in Santa Cruz del Sur Fishing Enterprise
According to the planned chronogram, the new fishing system will be introduced in
shrimp vessels of Santa Cruz del Sur Fishing Enterprise, at the 2008­2009 seasons,
being dictated the legal provisions required for its fulfilment.

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ICES WGFTFB REPORT 2008
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Trinidad and Tobago
Suzuette Soomai Fisheries Division, Ministry of Agriculture, Land and Marine
Resources, St. Clair Circle, St Clair, Port of Spain, Trinidad and Tobago
Abstract
Three periods of gear trials were conducted over 2006 and 2007 in the artisanal fleet
and one period in 2007 in the semiindustrial and industrial fleets, overall covering an
estimated 25% of the national trawl fleet. Gear trials involved modifying the existing
trawl net, testing of two bycatch reduction devices (BRDs) namely the fisheye and
square mesh panel, and testing of a new monofilament trawl net received from Mex
ico and aimed at reducing the level of discards of bycatch caught in the artisanal
shrimp trawl fishery. Overall results are insufficient to determine the effectiveness of
each BRD in reducing discards. Modifications to the existing net and the new mono
filament net however showed favourable results with regard to making fishing op
erations more efficient. Joint gear testing between the Fisheries Department and the
fishing industry has been beneficial in educating fishers and promoting co
management of the trawl fishery. Technical assistance from the National Fisheries
Institute of Mexico and from the FAO was instrumental in technology transfer and
enhancing fisheries research in Trinidad and Tobago. Gear testing allowed for col
laboration with Venezuela on joint research in the Gulf of Paria and the Columbus
Channel where the shrimp and groundfish resources are shared.
Introduction
The shrimp trawl fishery of Trinidad and Tobago targets five penaeid shrimp species
(Litopenaeus schmitti, Farfantepenaeus subtilis, F. notialis, F. brasiliensis, Xiphopenaeus
kroyeri). Groundfish bycatch of commercial importance is the sciaenids (Cynoscion
spp, Macrodon ancylodon, Micropogonias furnieri), gerreids (Diapterus spp.), lutjanids
(Lutjanus spp., Rhomboplites aurorubens), haemulids (Haemulon spp., Genyatremus lu
teus, Orthopristis spp.) and ariids (Bagre spp, Arius spp) (Kuruvilla et al., 2001). In
Trinidad, the resources are exploited by an artisanal, semiindustrial and industrial
trawl fleet. The shrimp and groundfish resources in the main trawling grounds in the
Gulf of Paria and Columbus Channel are considered to be shared stocks exploited by
the fleets of both Trinidad and Tobago and Venezuela.
The high levels of bycatch and discards is of great concern since only a small portion
of the bycatch is retained and landed and most is discarded at sea. An estimated 90%
of the bycatch of artisanal vessels, and 71% of the bycatch of the semiindustrial fleet,
is discarded and most are juvenile fish of other important coastal fisheries (Kuruvilla
et al., 2000). This is one of the main sources of conflict between the trawl fishery and
other fisheries such as the artisanal gillnets and lines. In a 1994 local knowledge sur
vey fishers noted a decline in catches and the general perception was that trawling
was responsible for destruction of the seafloor and juvenile fish (Ramjohn, 1995).
The high level of bycatch and subsequent discarding is due to two main factors.
Firstly, the shrimp trawl fishery is a tropical multispecies coastal fishery targeted by
a gear that is relatively unselective. Secondly, the vessel used for trawling have a lim
ited hold capacity and to maintain net profits only the target shrimp species and by
catch for which there is commercial value is landed.

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ICES WGFTFB REPORT 2008
Methods
Artisanal Fleet
The artisanal fleet targets mainly Litopenaeus schmitti and Xiphopenaeus kroyerii. The
net currently in use by the fleet consists of a flat trawl net made of multifilament
twine with a head rope length of 34 feet and mesh size of 1 ¼ inches. In November
2006 a double foot rope was introduced into the design of the traditional net. The
second foot rope was made of chain and was separated from the main foot rope by
nylon twine strings. Steel triangles were also used to obtain the desired separation
along the whole length of both foot ropes. Trawls were made at an average depth of
1.4 m and towing speed from 2.5 to 3.2 knots (Soomai and Seefoo, 2006).
In May 2007, a fisheye was installed in the artisanal trawl net between the last panel
of the trawl body and the codend. Separate experiments were conducted using a
square mesh panel in place of the fisheye. Paired trawls were conducted using two
vessels and the experimental gear from above (Net 1) and the control net (Net 2)
where:
· Net 1: Flat trawl net with head rope length 34 feet, mesh size 1 ½ inches;
· Net 2: Flat trawl net with head rope length 34 feet, mesh size 1 ¼ inches.
Trawl doors were used in all of the trials. (Soomai, 2007).
In October November 2007, gear trials commenced on a new prototype monofila
ment trawl net received from the INP, Mexico. The new net was rigged, tested and
modified, to ensure that it was fishing well in local conditions (Soomai, 2008). Head
rope length was 46.5 feet with 3/8 inch diameter nylon rope and monofilament net of
8 10 twine gauge. The new gear was tested against the previously modified multi
filament net (control net) and with the fisheye and square mesh panel installed.
Semi-industrial fleet
The semiindustrial trawl fleet targets Farfantepenaeus notialis and F. subtilis. The main
characteristics of the trawl system were:
Head rope length: 34 feet
Foot rope length: 38 feet
Tickle chain length: 35 feet
Mesh size: 1 ¾ inch
Otter boards: wood and steel, 6 feet long, 34 inches high, an angle of attack
of approximately 24°.
Bridles: 20 fathoms long made of 7/16 inch diameter steel wire.
To install the fisheye in the experimental net, a netting extension of 30 by 100 meshes
of 1 5/8 inches was prepared and inserted between the last panel of the trawl body
and the codend. A second foot rope made of chain was installed in this net and was
separated from the main foot rope by nylon twine strings 8 inches long. Paired trawls
were conducted at depths of 6 9 fathoms in the Gulf of Paria and average trawling
time was 3 hours/haul at a towing speed of 3.0 knots (Soomai, 2007).
Industrial Fleet
The industrial fleet targets Farfantepenaeus notialis and F. subtilis. The industrial trawl
fishing gear and its rigging (otter boards, bridles, tickle chain) was slightly bigger in

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ICES WGFTFB REPORT 2008
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dimensions to those of the semiindustrial vessels, except in the case of the former,
because of the outriggers; two equal nets are towed at each side.
Sea trials were conducted in the Gulf of Paria at depths of 3 ­ 8 fathoms and average
trawling time was three hours/set. Fisheye and square mesh BRDs were tested in
separate sets. The same fish eye and netting extension used in the semiindustrial
trawler was installed in the starboard trawl net. A square mesh panel was inserted in
a netting extension of 30 by 120 meshes of 1­5/8 inches and was also installed in the
starboard trawl net. Due to the difference in catches and operational dimensions ob
served between the trawls, the square mesh panel was also tested in the port side
trawl net (Soomai, 2007).
Results
Artisanal Fleet - Multifilament Net
Results were inconclusive in determining the effectiveness of the gear modification.
Overall, analysis of the data collected was inconclusive in determining the effective
ness of the fisheye and the square mesh panel in terms of bycatch reduction. There
was a 50% reduction in shrimp catch in the experimental net and the level of retained
fish did not increase in the experimental net compared with the control net.
Artisanal Fleet - Monofilament Net
There was a reduction in the capture of unwanted bycatch in the new monofilament
net with a 13% decrease in discarded bycatch to retained bycatch ratio and a 27% de
crease in the discarded bycatch to total catch ratio. Larger shrimp catches were re
corded however smaller sized shrimp were caught in the monofilament net. The
monofilament net was able to operate efficiently in a variety of water conditions and
at the speeds of 2.5­3.0 knots. Trawling with the monofilament net was more fuel
efficient.
Semi-industrial Fleet
The species composition was generally the same in the both the experimental (fish
eye installed) and control nets. The data collected was insufficient to determine the
effectiveness of the fish eye in bycatch reduction. The double foot rope was discon
tinued since it was stirring up too much sediment as a result of the shallow area of
trawling operations.
Industrial Fleet
There was a 32% reduction in the average weight of the total catch in the experimen
tal net (fisheye or square mesh installed) and the shrimp to retained bycatch ratio was
estimated at 1:1. However it was estimated that 90% of the bycatch was discarded
from both the control net and from the experimental net. Overall the data was unable
to provide a definite indication that the BRD was effective in reducing discarded by
catch.
Lessons Learnt
The high discard levels from trawlers put the fishing industry at risk of being the tar
get of environmental groups making themselves vulnerable to attack and possible
closure of the fishery. Fishers need to become more responsible for their role in con
tributing to reduction of resources and take part in research into more environmen
tally friendly practices.

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ICES WGFTFB REPORT 2008
Technical assistance from Mexico and the FAO was integral in conducting gear trials.
Trinidad and Tobago needs to enhance its technical capabilities with regard to fishing
gear technology in order to effectively support the fishing industry through future
testing and introduction of more efficient trawl gear.
The formation of the National Steering Committee (NSC), comprising trawl fishers
and vessels owners, was the first formal exercise to involve the participation of the
fishing industry in comanagement of fisheries resources. Involvement of fishers in
research in collaboration with the government was an initial attempt at participatory
management. There is an increase in awareness and commitment within the trawl
community towards future cooperation with fisheries authorities.
Data collection under Project EP/GLO/201/GEF helped to fill data gaps in the indus
trial trawl fishery. National stock assessments for whitemouth croaker (Micropogonias
furnieri) and lane snapper (Lutjanus synagris) were completed and showed the stocks
to be fully to overexploited (Soomai and Porch 2006; Yanagawa et al 2006). A study
on the importance of bycatch and discards to the social and economic wellbeing of
associated fishing communities was also completed (Hutchinson et al., 2007). The
trawl industry plays a significant social role in maintaining livelihoods in these rural
communities.
Knowledge gained through the Project was used in the development of revised ma
rine policy and fisheries legislation in 2006. Issues related to bycatch and discards
and the use of environmentally sensitive gear are listed as implementation strategies
under the government's draft policy objectives to maintain ecosystem health and sus
tainable fisheries for the future.
Future Plans
· Conduct additional testing of the monofilament net, fisheye and square
mesh panel BRDs to determine their effectiveness in reducing discards.
· Conduct tests on the semiindustrial and industrial fleets using new nets
made of Dyneema netting and new otter boards as the experimental gear.
· Urgent consideration will be given to implementing management meas
ures such as enforcing areas of operation as prescribed under national
regulations, since the artisanal fleet is operating in very shallow waters.
Movement to deeper waters is expected to reduce the catch of juveniles, in
the absence of a BRD.
· Trinidad and Tobago will continue to participate in global and regional
initiatives aimed at reducing discards from the trawl fishery.
References
Hutchinson, S., Seepersad, G., Singh, R., Rankine, L. 2007. Study on the SocioEconomic Impor
tance of Bycatch in the Demersal Trawl Fishery for Shrimp in Trinidad and Tobago. De
partment of Agricultural Economics and Extension, Faculty of Science and Agriculture,
The University of the West Indies, St. Augustine, Trinidad and Tobago.
Kuruvilla, S., Ferreira, L., Soomai, S., and Jacque, A. 2000. Economic performance and techno
logical features of marine capture fisheries: the trawl fishery of Trinidad and Tobago. Re
gional Workshop on the Effects of Globalization and Deregulation on Fisheries in the
Caribbean. Castries, St. Lucia, 4 December, 2000. Fisheries Division, Ministry of Agricul
ture, Land and Marine Resources, Trinidad and Tobago.
Kuruvilla, S., Ferreira, L., and Soomai, S. 2001. National Report of Trinidad and Tobago. In
Tropical shrimp fisheries and their impact on living resources. Shrimp fisheries in Asia:

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ICES WGFTFB REPORT 2008
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Bangladesh, Indonesia and the Philippines; in the Near East: Bahrain and Iran; in Africa:
Cameroon, Nigeria and the United Republic of Tanzania; in Latin America: Colombia,
Costa Rica, Cuba, Trinidad and Tobago, and Venezuela. FITT/C974. Food and Agriculture
Organization, Rome.
Ramjohn, D. 1995. Results of fisheries local knowledge survey in the Gulf of Paria. FAO/UNDP
Project FI:DP/INT/91/007 "Integrated Coastal Fisheries Management". Fisheries Division,
Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago.
Soomai, S., and Porch, C. 2006. The status of lane snapper (Lutjanus synagris) resources in
Trinidad and Tobago. In Technical Report of the Caribbean Regional Fisheries Mechanism
(CRFM) 2nd Scientific Meeting, Port of Spain Trinidad, March 2006.
Soomai, S., and Seefoo, A. 2006. Report of Gear Trials conducted by the Fisheries Division,
Ministry of Agriculture, Land and Marine Resources (MALMR) in collaboration with the
National Fisheries Institute (INP), Mexico, November 12 ­ 25, 2006. Project
EP/GLO/201/GEF "Reduction of Environmental Impact from Tropical Shrimp Trawling,
through the Implementation of Bycatch Reduction Technologies and Change of Manage
ment.". Fisheries Division, Ministry of Agriculture, Land and Marine Resources, Trinidad
and Tobago.
Soomai, S. 2007. Report of Gear Trials conducted by the Fisheries Division, Ministry of Agricul
ture, Land and Marine Resources (MALMR) in collaboration with the National Fisheries
Institute (INP), Mexico, May 21 ­ 31, 2007. Project EP/GLO/201/GEF"Reduction of Envi
ronmental Impact from Tropical Shrimp Trawling, through the Implementation of Bycatch
Reduction Technologies and Change of Management.". Fisheries Division, Ministry of Ag
riculture, Land and Marine Resources, Trinidad and Tobago.
Soomai, S. 2008. Report of Trawl Gear Trials, 4 October ­ 28 November, 2007. Project
EP/GLO/201/GEF "Reduction of Environmental Impact from Tropical Shrimp Trawling,
through the Implementation of Bycatch Reduction Technologies and Change of Manage
ment." Fisheries Division, Ministry of Agriculture, Land and Marine Resources, Trinidad
and Tobago.
Yanagawa, H., Ferreira, L., Martin, L., and Soomai, S. 2006. Preliminary data analysis of two
fish species in Trinidad using the SPR (Spawning stock biomass Per Recruit) method.: 1.
Whitemouth croaker (Crocro), Micropogonias furnieri; 2. Lane Snapper, Lutjanus
synagris. Produced for the Project for the Promotion of Sustainable Marine Fisheries Re
source Utilisation, JICA. Fisheries Division, Ministry of Agriculture, Land and Marine Re
sources, Trinidad and Tobago.
Columbia
Maria Rueda and Farit Rico, Instituto de Investigaciones Marinas y Cosetras
ABSTRACT
Quantification of the tropical shrimp trawling impact and mechanics to reduce it on
both Caribbean and Pacific coasts were evaluated. The methodological approach in
cluded census of the fishing technology, monitoring, workshops, trials and fishing
experiments. The census revealed that vessels and net designs are 30 years old. Fish
ing monitoring showed the following catch composition: shrimp 8%, incidental catch
27% and discards 65% for the Caribbean; while for the Pacific shrimp is 5%, inciden
tal catch is 43% and discards is 52%. In this sense new trawl nets were designed, in
troducing new netting materials and BRDs (fisheye and TED). 12 Trawl nets
prototype were manufactured during 2 workshops, where 60 fishers were trained in
fishing trials. These trawl nets were used in fishing experiments comparing catches of
an experimental vessel (using prototype nets) with those of a control vessel (using
traditional nets) to test reduction of bycatch and fuel consumption if possible. For the

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ICES WGFTFB REPORT 2008
Caribbean 80 hauls paired showed that the bycatch was reduced as follows 20%
(fisheye), 41% (TED), 54 (fisheye + TED); while for the Pacific 240 hauls showed re
ductions of 28% (fisheye), 23% (TED) and 57% (fisheye + TED). In the Caribbean the
fuel saved was 17%, whereas on the Pacific the save was 25%. Current decrease of the
shrimps stocks and high fuel prices, are part of the issues that the fishery manage
ment agency in Colombia faces to change of management.
2000
1500
t
)
(
r
a
u 1000
pt
Ca
500
0
CO
CI
D
FA
Tipo de captura

Figura 1. Composición de la captura total (t) en la flota camaronera de aguas profundas del Pacífi
co colombiano.

Merito
Cabezudo
Marfilillo
Zafiro
Mero

Pejerey
al
nt
Cherna
i
de
Perla
Peladilla
i
nc
r
a
Calamar
u
pt
Pargo
a
C
Zafirillo
Toyo y Raya
Lenguado
Cagua
Manteco
Merluza
0
5
10
15
20
25
Captura (t)

Figura 2. Composición por productos de la captura incidental (t) desembarcada por la flota cama
ronera de aguas profundas del Pacífico colombiano.

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ICES WGFTFB REPORT 2008
| 243
Munida gracilipes
Descarte Total = 6.7 t
Selene peruviana
Citharichthys spp.
Merlucius angustimanus
Squilla panamensis
Coelorhincus canus
Squil a biformis
Solenocera agassizi
Taxa
Ophidium spp.
Physiculus nematopus
Porichthys margaritatus
Trichiurus lepturus
Heterocarpus vicarius
Munida refulgens
Scorpaena spp.
0
5
10
15
20
Captura (% en peso)

Figura 3. Principales taxa del descarte en la flota camaronera de aguas profundas del Pacífico co
lombiano.
a
Hembras
Machos
Hembras
Macho
350
35
TMM
TM
300
30
250
25
a
ci 200
20
en
150
15
r
ecu
F 100
10
50
0
8.5
9
9.5
10 10.
1 5 11 11.
1 5 12 12.
1 5 13 13.
1 5 14 14.
1 5 15 15.
1 5 16 16.
1 5 17 17.
1 5 18
1
Longit
ngi ud total (
al cm)
cm
Hembra
r s
a
Mac
Ma ho
h s
c
350
b
TMM
TM
Hemb
m r
b a
r s
Macho
h s
o
300
100
TMM
250
i
a
75
a
200
a
uanc
c 150
50
e
ecuenci
Fr
ecuenci
100
Fr 25
50
0
0
11
11.5
11.
12
12.5
12.
13
13.5
3.
14
14.5
14.
15
15.5
15.
16
16.5
6.
17
17.5
17.
18
18.5
8.
7
7.5
8
8.
8 5
9
9.5
10
1
10.
1 5
11
11.5
12
12.5
13
13.5
14
14.5
15
15.5
16
1
Longit
gi ud t
t
ot
ud t a
ot l (
l c
( m)
m
Longitu
Longi d t
tu
o
d t tal l(c
m)

Figura 4. Distribuciones de frecuencias por sexo indicando la TMM. a) Farfantepenaeus breviros
tris; b) F. californiensis y c) Solenocera agassizi.
Costos Totales
Ingresos Totales
3000
2500
) 2000
$
(
s
e
n 1500
illo
M 1000
500
0
II
III
IV
Bimestres

Figura 5. Comportamiento bimensual de los costos y los ingresos totales de la flota camaronera de
aguas profundas en el Pacífico colombiano. El área entre las líneas representa la renta económica.

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ICES WGFTFB REPORT 2008
80
70
60
h) 50
(
kg/
CO 40
30
CPUE
20
10
Median
0
III
IV
V
25%-75%
Min-Max
Bimestres

Figura 6. Abundancias por bimestres de captura objetivo CO.

120
100
)
80
/
h
g
(k PAC 60
FAEU
CP
40
20
0
III
IV
V
Bimestres

Figura 7. Abundancias por bimestres de la fauna acompañante del camarón de aguas profundas
(FACAP). Las barras de error denotan intervalos de confianza del 95%.
a
50
40
h)
(
k
g/
CO 30
UE
CP
20
10
A
B
C
Estr
t a
r t
a o
t s
b
125
100
h)
75
(
k
g/
P
A
C
FA
50
CPUE
25
0
A
B
C
Estr
t a
r t
a o
t s

Figura 8. Abundancias por estrato de profundidad de a) captura objetivo (CO) y b) fauna acompa
ñante del camarón de aguas profundas (FACAP). Las barras de error denotan intervalos de con
fianza del 95%.

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ICES WGFTFB REPORT 2008
| 245
References
Alverson, D., M.H. Freeberg, S.A. Murawski y J.G. Pope. 1994. A global assessment de fisheries
bycatch and discards. FAO Fish Tech. Pap. 339, Rome, 233 p.
Andrade, R. 2000. Evaluación de captura, esfuerzo y algunos parámetros poblacionales de los
camarones café (Farfantepenaeus californiensis) y rojo (Penaeus brevirostris) en el Pacífico co
lombiano. Tesis Universidad del Valle. 65 p.
Conapesca,
2005.
Noticias
Sagarpa.
Disponible
en
Internet.
URL:
http://www.conapesca.sagarpa.gov.mx
De la Pava, M.L. y C. Mosquera. 2001. Diagnostico Regional de la Cadena Camarón de Pesca
en el Pacífico Colombiano. Documento Técnico presentado al Ministerio de Agricultura y
Desarrollo Rural. ACODIARPE, Buenaventura, 41 p.
Eayrs, S. 2007. Guía para Reducir la Captura Incidental (bycatch) en las Pesquerías por Arrastre
de Camarón Tropical. Edición revisada. FAO. Roma, 108 p.
EJF. 2003. Squandering the seas: How shrimp trawling is threatening ecological integrity and
food security around the world. Environmental Justice Foundation, London, 45 p.
FAO. 1995. Código de conducta para la pesca responsable. FAO. Roma, 46 p.
Fischer, W., F. Krupp., W. Schneider., C. Sommer., K.E. Carpenter y V.H. Niem. 1995. Guía
FAO para la identificación de las especies para los fines de la pesca. Pacífico centro
oriental. Vol. IIII. FAO. Roma, 1813 p.
Garcia, S.M. 1996. The precautionary to fisheries and its implication to fisheries research, tech
nology and management: an updated review. En "Precautionary Approach to Fisheries".
Part 2. FAO Fisheries Technical Paper No. (350/2), 1­76.
INCODER. 2007. Resolución N° 2852 del 22 de diciembre de 2006. INCODER. Bogotá, 7 p.
Kelleher, K. 2005. Discards in the Worlds Marine Fisheries. An Update. FAO Fish. Tech. Pap.
470, Rome, 131 p.
Lewison, R.L., L.B. Crowder, A.J. Read y S.A. Freeman. 2004. Understanding impacts of fisher
ies bycatch on marine megafauna. TREE, 19: 598­604.
Madrid, N y W. Angulo. 2002. Evaluación biológicopesquera del recurso Camarón de Aguas
Profundas en el Pacífico Colombiano. Marzo 2001 ­ Febrero 2002. Informe Técnico. Agro
pesquera Bahía Cupica Ltda. Buenaventura, 70 p.
Madrid, N y M. Rueda. 2007. Análisis para la estimación de cuotas de pesca del camarón de
aguas profundas en el Pacífico colombiano basado en registros históricos. Informe Técni
co. INVEMAR. Santa Marta, 17 p.
Morgan, L.E y R. Chuenpagdee. 2003. Shifting Gears. Addressing the Collateral Impacto de
Fishing Methods in U.S. Waters. Pew science series on conservation and the environ
mental, Washington, 42 p.
Pauly, D y G.I. Murphy. 1982. Theory and management of tropical fisheries. ICLARM/CSIRO,
Manila.
Pineda, F.H. 1995. Biología del camarón de aguas someras Penaeus occidentalis, P. stylirostris,
y P. vannamei, en la Costa Pacífica colombiana. Documento Técnico del INPA. Buenaven
tura, 60 p.
Puentes, V., N. Madrid y L. Zapata. 2007. Catch composition of the deep sea shrimp fishery
(Solenocera agassizi Faxon, 1893; Farfantepenaeus californiensis Holmes, 1900 and Farfan
tepenaeus brevirostris Kingsley, 1878) in the colombian Pacific ocean. Gayana. 71 (1): 84­
95.
Robertson, D.R y G.R. Allen. 2002. Peces costeros del Pacífico oriental tropical: Un sistema de
información. Institutto Smithsonian de Investigaciones Tropicales, Balboa, República de
Panamá.

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ICES WGFTFB REPORT 2008
Rueda, M., J.A. Angulo, N. Madrid, F. Rico y A. Girón. 2006. La pesca industrial de arrastre de
camarón en aguas someras del Pacífico colombiano: su evolución, problemática y perspec
tivas hacia una pesca responsable. Instituto de Investigaciones Marinas y Costeras "José
Benito Vives De Andréis" INVEMAR. Santa Marta, 60 p.
Sagarpa. 2003. Informe del taller Nacional sobre selectividad de sistemas de pesca de arrastre
para camarón. Implicaciones para el ordenamiento pesquero. SagarpaConapescaINP.
Mazatlán, Sinaloa, 32 p.
Seijo, J.C., O. Defeo y S. Salas. 1998. Fisheries bioeconomics. Theory, modelling and manage
ment. FAO Fish. Tech. Pap. 368, Rome, 176 p.
Zapata, L.A., G. Rodríguez, B. Beltrán, G. Gómez, A. Cediel, R. Avila y C. Hernández. 1999.
Evaluación de recursos demersales por el método de área de barrida en el Pacífico colom
biano. Bol. Cient. Del INPA, No. 6: 177­226.
Venezuela
Luis Maracano and Jose Alio, Instituto Nacional de Investigaciones Agricola
Edif. (INIA), lmarcano@inia.gob.ve and Jalio@inia.gob.ve
Abstract
Discarded by catch of the industrial shrimp fleet in Venezuela is about 60% and is
considered a major environmental impact in the country. Tests were conducted to
reduce discards in the industrial and artisanal shrimp fleets. The industrial shrimp
fishing is performed by 260 Florida type vessels, targeting shrimp and fish. The use of
TED is mandatory. Testing of bycatch reductions devices (BRD) like fish eye showed
a significant reduction in discards but also severe losses of commercial catch. The
square mesh panel did not provide significant reductions of discards. The lower or
lifted lower rope rendered an average 25% reduction in discards and no significant
loss of commercial catch. The artisanal shrimp fishing is done with small trawls and
beach seines. The former was modified with Nordmore grid, square panel and fish
eye. Better results were obtained with the fish eye, which showed a reduction in dis
cards close to 70%, but a 30% shrimp loss was confronted. Tests of BRDs will con
tinue after FAOGEF project ends in 2008, organizing workshops with fishers to show
construction and use of the devices, and sharing of results with researchers and fish
ers of countries in the region is to be promoted.
Introduction
Discarded by catch in the Venezuelan fisheries has been assessed only in the shrimp
(Marcano et al. 2001) and tuna long line fisheries, although preliminary results sug
gest that there could be significant amounts of discards in some artisanal and indus
trial purse seine tuna fisheries. The high proportion of bycatch in the trawl fisheries
gives evidence of a large environmental impact by this sector and casts a wrong im
age of the fishing industry to the general public. This could have induced drastic po
litical measures recently taken by the Venezuelan Government with respect to
trawling in the country. Since late 80's there have been trials to promote selectivity in
the trawl fisheries. The assistance of the FAOGEF project on shrimp gear modifica
tion and the technical support from consultants, allowed a fast testing of different
alternatives of gear modifications or the introduction of gears from other parts of the
world on the local shrimp fishing, which improved significantly the efficiency of the
shrimp fishing sector and reduced its environmental impact.

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ICES WGFTFB REPORT 2008
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Methods
The study was made in the five most important shrimp fishing grounds in the lower
Caribbean Sea: Lake Maracaibo estuary, Gulf of Venezuela, eastern platform, the Gulf
of Paria and in front of the Orinoco river delta. Each shrimp fishery was evaluated
with respect to: fishing gear in use, operational methods, region of operations, cap
tures, landings, and commercial and discarded by catch. Tests on the industrial
shrimp trawling were conducted by trained observers on board of Florida type ves
sels, which use two nets, one on each side of the boat; one unmodified net served as
control. The use of TED is mandatory. Three modifications were tested, fish eye,
square mesh panel and double or lifted lower rope. TEDs were not used during ex
perimental trawls. Tests on artisanal shrimp fishing included the modification of a
small trawl with an increase mesh size in the sac, or the use of a Nordmore grid, a
square mesh panel or the fish eye in the sac. Tests in the artisanal fleet were per
formed using several vessels operating close by in the same fishing grounds, one
group with traditional nets serving as control. The replacement of the traditional
beach seine by the Suripera net from Mexico or by the bottom entangling net was also
tested.
Results
The fleet of 260 industrial trawlers uses a similar type of net, semiballoon with two
covers, with 20/21 m upper/lower ropes that could go to 30/32 m depending on size
of vessel and engine power. There are about 10 stern trawlers targeting fish but were
not included in the study. The catch composition of the industrial trawl is about 4%
shrimp, 26% fish, molluscs and other crustaceans that are landed, and about 60% dis
cards. Fish eye in the industrial trawl induced reductions in discards of 40%, but also
losses close to 50% in average of the commercial catch of fish, which on top of the
45% loss caused by the use of the TED, makes the device unacceptable by the fleet.
The square mesh panel rendered only 4% reductions in discards, but there were
problems in the rigging of the gear, so no conclusive results could be obtained with
this device. The lower double rope gave consistent results with an average 25% re
duction in discards while the commercial CPUE was maintained or improved. The
artisanal shrimp trawl fishery in the Orinoco river delta and the lower eastern Carib
bean Sea operates with discards of nil to 90%. Tests with the Nordmore grid in the
artisanal trawl fleet operating in the Orinoco river delta showed a severe clogging of
the grid with the large load of debris carried by the river. This device seems to re
quire cleaner waters to be used efficiently. The square mesh panel gave large shrimp
losses (beyond 40%) since the fishers leave the net lie slack on the bottom before re
trieving it on board after the tow. The fish eye placed at 1,5 m away from the knot in
the sac induced reductions of discards close to 70%, although the loss of shrimp could
be nil to 30%. Placing the fish eye closer to the end of the sac promoted shrimp loss,
and further away from it did not render significant reductions in discards. A back
wash panel may have to be used behind the fish eye to prevent the escape of shrimp
through the BRD during the retrieval process of the catch. The mandatory use of fish
eye in the artisanal trawl and the lower rope in the industrial trawl is suggested and
may be included in the fishing regulations. The beach seine used in many artisanal
shrimp fisheries is not amenable to structural modifications to reduce discards, be
cause shrimp loss cannot be prevented. There are possibilities to replace it with the
Suripera net tested in Lake Maracaibo, Gulf of Venezuela and eastern platform. Only
in the former area was the shrimp density large enough to show similar shrimp
CPUE values with respect to the traditional beach seine nets (20 kg/h) with 2% dis
cards, while the beach seine has 80% discards. Unless shrimp density if very high, the

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ICES WGFTFB REPORT 2008
CPUE of the Suripera net is too low due to the reduced swept area that is covered by
the gear. The bottom entangling net showed discards of 40% and a shrimp CPUE of
xx kg/h which also makes it a good system to replace the beach seine.
Lessons learned
There has been a severe lack of motivation by fishers to test modifications of the
shrimp trawl gear in general to improve its selectivity during the 50+ years of the
shrimp fishery in Venezuela. This attitude could be a consequence of a castrating en
forcement of the fishing regulations. In large contrast, there were great changes in the
number of vessels (from 200 in 1980 to 450 in 1990, to 260 currently in operation),
fishing power, materials for net construction (replacing PA for PE) and use of elec
tronics on board. The FAOGEF project provided an opportunity for all fishers to get
involved in the solution of the common problem of the large discards rate in the
shrimp fleet. It was also a means to improve the image of the fishing sector in front of
the general public, which may see the fishers as predators and destructors of the ma
rine environment. Fishers seem to be willing to incorporate better fishing practices to
their usual operations.
Future plans
· Complete validation tests of gear modification or introduction of new gear
in the artisanal shrimp fishing sector.
· Organize workshops with shrimp fisher's communities along the country
to show the use of the new technology and demonstrate its use.
· Share results with colleagues and fishers from other countries in the region
in order to speed up regional results.
References
Marcano, L.A., Alió, J.J., Novoa, D., Altuve, D.E., Andrade, G., and Álvarez, R.A. 2001. Revi
sión de la pesca de arrastre en Venezuela. En: Tropical Shrimp Fisheries and their Impact
on
Living
resources.
FAO
Fisheries
Circular
974:
330­378,
Roma.
http://www.fao.org/docrep/007/y2859e/y2859e13.htm#1

Mexico
Dr Miguel Angel Cisneros Mata, Instituto Nacional de Pesca, Mexico
1. Meetings of the National Steering Committee held:
a ) Mazatlan, Sin. August 2007. Shrimp Fishery Technical Working
Group.
b ) Mazatlán, Sin. September 2007. Committee on Fisheries and Aquacul
ture for the Pacific coast.
Progress of each national project activity
PACIFIC COAST
A 10 day's cruise onboard commercial vessel at the west coast of Baja California Pen
insula face operations problems since there was a huge presence of a crustacean
known as "langostilla" (Pleuroncondes planipes); trawls sets were rather short and non
representative in all shrimp fishing ground areas.

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Due to engine brakedown of BIP XI, an 8 days cruise for sea trials in the Upper Gulf
of California was made; results confirmed advantages of prototype RSINPMEX, in
previous trials. Comparison of bycatch reduction and catch efficiency of prototype
was possible since a set of traditional trawl nets were tested; all expenses were cov
ered by the Walton Foundation through WWF.
ATLANTIC COAST
Arrangements were made to use commercial trawlers for testing of new net designs
and the introduction of BRDs at Tampico, Tamaulipas and Ciudad del Carmen,
Campeche. Since the fleet composition and technical characteristic of trawl nets has
changed, a survey was carried out in those two ports, for data collection of 30 shrimp
trawlers.
Two meetings were held with vessel owners from the Atlantic coast, where the
stockholders asked to include testing of new otter boards (High Lift) used in the Pa
cific phase of the project, in order to achieve further fuel savings.
Due to lack of researchers it was decided that all sea trials were going to have place
during the shrimp ban of the Atlantic; cost of testing/fishing operations will be cover
by the stockholders, except DSA payment of researchers and new gear and devices.
Research for artisanal shrimp fisheries have started in the Upper Gulf of California in
order to reduce the impact of enmeshing shrimp nets on endemic endangered por
poise (Vaquita); also, due to mixed presence of juvenile white shrimp (Litopenaeus
setiferus) while trawling for Sietebarbas shrimp (Xiphopenaeus kroyeri), a new project
will start in 2008 in the Atlantic coast, to introduce a new trawl net with short front
upper panel or no front upper panel.
Workshops, training, or demonstration activities undertaken
During July two joint campaigns were carried out jointly with Cuba and Costa Rica,
in order to asses the accomplishments of both countries projects.
CUBA:
Locations: La Habana and Santa Cruz del Sur.
Activities: Meeting with FAOCuba representatives; Meeting with Authorities from
Fisheries Research Center (CIP) and National Steering Committee; Meeting with di
rectors of the Santa Cruz del Sur Enterprise; Sea trials; report to Authorities from CIP
and Steering Committee.
COSTA RICA:
Main activities were meeting with FAOCosta Rica Representative, construction of
devices to facilitate testing of double foot rope and sea trials at Gulf of Nicoya on
board B/M CAPITÁN GERARD.
A total of 12 trawl sets were done to test fisheye, square mesh panel and double foot
rope.
SURIPERA WORKSHOP
From 20 ­ 27 November an international workshop was held at Culiacan, Sinaloa,
Mexico, with participants from Colombia (2), Costa Rica (1), Cuba (1), Philippines (2),
and Mexico (11). Activities include design, construction, testing and fishing opera
tions with suriperas.

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ICES WGFTFB REPORT 2008
General comments on the current status of the shrimp-trawling industry
Although official statistics of shrimp fishery for 2006 and 2007 are not available yet, a
general overview of shrimp production is given in Figure 1 (2005 data is considered
still preliminary).
Total shrimp production has increased in the last 10 years, mainly due to the signifi
cant raise of shrimp farming production. Apparently industrial and artisanal shrimp
fishing is stable over the last 10 years; however there is a slight decrease for the in
dustrial fishing, mainly attributed to the Pacific.


Figure 1. Shrimp production by origin.
Data of shrimp production of industrial, artisanal and shrimp farming from each
coast for 2005 are given in Table 1 and 2.
Table 1. Shrimp production by origin in the Pacific Coast.
Ton
%
Industrial
28,734.0
21.5
Artisanal
17,905.6
13.4
Aquaculture
87,137.7
65.1
Total Pacific
133,777.3
100.0

Table 2. Shrimp production by origin in the Atlantic Coast.
Ton
%
Industrial
8,300.0
33.9
Artisanal
13,285.3
54.3
Aquaculture
2,903.4
11.9
Total Atlantic
24,488.7
100.0

Number of trawlers in the Pacific coast has a very slight reduction; however, income
has been affected from catch reduction or international market price reduction.
In the Atlantic coast, there has been an important reduction of the number of shrimp
trawlers, through a government program of buyingout shrimp licenses/trawlers.

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| 251
Catches per vessel have increase significantly over the last three years, as well as in
come; although some fishing grounds have been closed, economic impact to stock
holders seems not to be important due to increased catches.
Some vessel owners in the Pacific coast that have participated in the project, are ap
plying for certification of "clean shrimp" or "green shrimp", with USA shrimp bro
kers through some NGOs, in order to get a "bonus" plus prices.
Process to certification of Suripera fishing operations will start during 2008, in order
to get a "clean shrimp" label.
Estimation of bycatch reduction:
a ) Total Number of shrimp trawlers: Total number of trawlers is in proc
ess of actualization since the program to reduce fishing effort by
means of buyingout commercial shrimp trawlers is still going on.
b ) Number of shrimptrawlers that used BRDs when the project started: 2
(only research vessels of INP)
c ) Number of shrimptrawlers currently using BRDs: Approximately 140,
mainly in the Pacific coast.
Nigeria
James Ogboona, Nigerian Institute For Oceanography And Marine Research
(NIOMR), Jamescogbonna@yahoo.com
Introduction
Nigeria is one of the participating countries involved in GEF/UNEP/FAO Shrimp
Fisheries Project titled: `Reduction of Environmental impact from Tropical Shrimp
Trawling through the introduction of Bycatch Reduction Technologies and change of
management'. The main objective is the reduction of bycatch in shrimp fisheries.
Nigerian Institute for Oceanography and Marine Research, (NIOMR) Lagos is cur
rently implementing 2 complementary research activities in the Eastern Gulf of
Guinea sub region of West Africa on the following:
a ) The development/adaptation of appropriate bycatch reduction tech
nologies for the shrimp trawlers in Nigeria and Cameroon. This tech
nical part of the project involved the construction of prototype Bycatch
Reduction Devices (BRDs) and Turtle Excluder Device (TED) for fleet
testing on board conventional shrimp vessels in Nigeria and Camer
oon. The awareness created has extended to other States in the sub re
gion including Togo Republic, Republic of Benin, Gabon, Sao Tome &
Principe and Equatorial Guinea.
b ) The design and conduct of a socioeconomic survey of the shrimp
trawl fisheries and the trading of their bycatch
The technical development/adaptation of reduction technologies
Turtle Excluder Devices (TEDs) are installed in the codend extension of shrimp trawl
nets as a management tool to reduce fishery related sea turtle mortality.
Trawl nets with bycatch reduction devices (BRDs) are also constructed in order to
mitigate the problem of juvenile and immature fish bycatch in shrimp trawling.

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ICES WGFTFB REPORT 2008
The duo of TED and BRD in the same trawl net is expected to function perfectly well
and complement each other without any drastic reduction in the quantity of shrimps.
The data recorded during comparative demonstration trials of trawl nets fitted with
TED, BRD codends and the traditional square mesh codend, are shown in Table 1. As
shown in Table 2 the results of analysis of variance (ANOVA) indicated that there
was no significant variation in the mean values of shrimps caught by the various
trawl net codends.
Table 1. Total catch by weight of fish and shrimp in hauls 1 ­ 4.
Species TED
Only T90
SMW
Trad
Shrimp
6.2
11.8
9.8
9.5
Com. Fish
109.3
125.3
104.0
109.0
Trash
91.0
70.8
112.0
126.3
Total
206.5
207.9
225.8
244.8

Table 1a. Catch by weight (% of traditional).
Species TED
Only T90
SMW
Trad
Shrimp
65.0%
120.0%
103.0%
100% (9.5kg)
Com. Fish
100.0%
115.0%
95.4%
100.0% (109.0kg)
Trash
72.0%
56.0%
88.7%
100.0% (126.3kg)
Total
84.4%
84.9%
92.2%
100%

Table 1b. Catch by category within tow (% of total catch per tow).
Species TED
Only T90
SMW
Trad
Shrimp
3.0%
5.7%
4.4%
3.9%
Com. Fish
52.9%
60.3%
46.0%
44.5%
Trash
44.0%
34.0%
49.6%
51.6%
Total
100%
100%
100%
100%

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ICES WGFTFB REPORT 2008
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Table 2. ANOVA Table on shrimps caught by trawl nets fitted with TED, BRD or Traditional
diamond mesh codend during demonstration trials.
Variations Degree
of
Freedom
SS
F
SSB=8.4675
R1=3
2.8225
3.071
SSW=11.03
AR=12
0.9192

SST=19.4975
15


F TAB (3,12)
P0.05=3.49
0.01 (3,12) = 5.95


ANOVA showed no significant difference (P>0.05) between the shrimps caught by
the various trawl net codends. This is an indication that there will be no drastic loss
of shrimps if the devices are properly installed and operated.
U.S.A. experts inspected the Fishing Companies in Nigeria in September 2007 to de
termine the degree of TED compliance by the Industrial fishermen as well as the en
forcement strategies of the Federal Department of Fisheries. This was undertaken
with a view to extend the certificate of TED compliance till 2009.
Workshops on the designs and construction/fabrication of bycatch reduction devices
including square mesh windows (SMW), 90° turned (gentle) codend and square mesh
codend (SMC) were conducted at the premises of Fishing Companies. The target
groups included mainly captains, net makers, deck hands and managers.
The number of participants during the 2day workshop per company is as follows:

FISHING COMPANIES
DATE
NO. OF PARTICIPANTS
Atlantic Shrimpers Ltd
2­23 August 2007
18
Barnarly Fisheries Ltd
24­25 August 2007
16
Honeywell Fisheries
26­27 August 2007
10
United Fisheries Ltd
28­29 August 2007
16
Karflex Fisheries Ltd
4­5 September 2007
12

The workshops conducted earlier at Taraboz Fisheries Ltd and ORC Fisheries in
cluded 32 and 18 participants respectively.
The adaptation rate of BRD codends of about 65% was more in favour of square mesh
window (SMW). During the period July ­ December 2007, Atlantic Shrimpers Lim
ited (ASL) completed the construction of a total of about 280 SMW codends i.e. 4
codends per vessel for about 70 shrimp trawlers owned by the industry.
It should be recalled that the recertification of Nigeria for TED compliance and per
mission to sell all categories of shrimps to USA markets rekindled the interest of the
Industrial Fishermen in Cameroon, Gabon and other member states in the sub region
in order to enjoy the same opportunity and benefit of higher prices for shrimp ex
ports. Therefore there is the need for technology transfer in terms of capacity building
and skills acquisition on the design, construction and operation of TED and BRD by

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ICES WGFTFB REPORT 2008
the participating States in order to achieve this objective and bring about uniform
regime of application and enforcement of the relevant fisheries laws and regulations
in the sub region. The same issue was highlighted in the draft convention that was
reviewed in Douala Cameroon between 19 and 20 December 2007 and at the various
meetings that were convened on harmonization of the fisheries laws and regulations
and the collaboration on the use of closely coordinated vessels monitoring system
(VMS) in the subregion.
In the light of the above, Dr. B.B. Solarin participated in the Gabon workshop con
ducted under the auspices of National Oceanographic Atmospheric Administration
(NOAA) of the United States. The workshop was convened to share experiences in
implementation of TEDs and other management solutions to reduce sea turtle mortal
ity in shrimp trawl nets. There was an oral presentation of the Nigerian experience.
The workshop also included practical demonstrations on TED construction as well as
demonstration trials at sea to test the performance on board commercial vessel. It cre
ated a lot more awareness among the Gabonese industrial fishermen, Managers and
Administrators. It was observed that it was important and desirable to maintain an
optimum grid angle of 55 degrees in order to improve TED performance.
Cameroon
Oumarou NJIFONJOU, IRADSRHOL PMB 77 Limbe, CameroonTel: +237 77
61 91 49; Email: njifonjo@caramail.com
INTRODUCTION
In Africa, the project concerns Nigeria and Cameroon waters. This area has vast fish
eries resources, which are critical to the food security of the region, but which are
currently severely threatened by over fishing, urban runoff and offshore petroleum
exploitation. The project is under the supervision of the Fisheries Department and is
implemented in Cameroon by the Fisheries and Oceanography Research Station
(SRHOL). The Artisanal shrimp fisheries utilizes more than 1000 fishermen and for
the moment the Industrial sub sector has 41 registered shrimp trawlers from Nigeria
and 30 based in Douala. Most of these vessels are shrimp trawlers with small mesh
sizes and this inevitably results in large quantities of juveniles. Bycatch and trash fish
constitute mostly 95% of the products caught and 75% of the finfish landed are juve
niles caught before first maturity.
The increase of the shrimp fishing effort over the years, the high level of fish caught
by shrimp trawlers, the continue reduction of the sizes of fish landed, the high price
of fish on the markets and the political will to conserve and sustain the fisheries re
sources are the main motivation for the establishment of bycatch reduction legisla
tion/regulations. In the new fisheries Law to be promulgated, BRDs and TEDs
utilization has been introduced as one of the basic requirements for the license appli
cation.
National Plan of Action for bycatch management and discard reduction
The objectives and activities of the overall national plan of action for bycatch man
agement and discard reduction are here summarized:
Objectives
· Ongoing evolution of the commercial shrimptrawling fisheries, with esti
mation of fishing efforts and landings;

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· Typical rate of shrimpcatch, bycatch and discards made over an annual
cycle by the commercial shrimptrawling fleet, both before, and after adop
tion of Bycatch Reduction Devices (BRDs) by the vessels;
· Socioeconomic changes and good governance which may be brought
about by the adoption of BRDs in the commercial shrimptrawling fleets.
Activities
· Onboard sampling/Observer program (data collection up to the end of the
project);
· Field demonstration of new technologies developed/adapted (workshops);
· Introduction of appropriate BRD and TED technology to shrimpfishing
fleets;
· Establishment of an appropriate database from data collected progres
sively by observers;
· Dissemination and extension of the results achieved;
· Promulgation of the new fisheries law;
· Management of the vessel Monitoring System (VMS) already installed in
the vessels operating in Cameroon;
· The study on socioeconomic impact of the By­catch trade in Cameroon
should continue particularly data collection and provision of alternative
means of livelihood;
· Data analysis and final reporting.
Sea trials demonstration
The sea trips organized during the last workshop (April 07) were undertaken on
board the commercial vessel belonging to PGT fishing company based in Douala and
freely offered for the occasion (in kind contribution of the private sector). The PGT
stern trawler used was a shrimper rigged with four nets, a quad rig, fishing simulta
neously as in Nigeria. This permitted comparative testing for the TED and BRD's at
the same time. The four traditional trawls were modified from left to right as TED
only outside, T 90 codend inside for the Port side, and for the Starboard side, Square
mesh window inside and Traditional codend outside, and 3 hauls, each of two hours
trawling were made and catches from different codends compared.
It should be noted that the BRD codends tested during the trials were left to the PTG
vessel to be tested continuously.
Results of the sea trials
The catch composition included mainly the croakers (Scianidae), sole (Cynoglossi
dae), threadfins (Polymenidae), shad, ethmalosa (Clupeidae), silver fish (Trichiuri
dae), and shrimps (penaeidae) notably Penaeus notialis, P. kerathurus and Parapenaeus
atlanticus. The catch composition was sorted into three major categories: Shrimps,
Fish of commercial value, Thrash fish or discards (constituted mainly of juvenile,
immature fish species and small pelagic).
The catch composition by weight is shown in Table 1 (first trip) and Table 2 (second
trip) below.

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ICES WGFTFB REPORT 2008
Table 1. First trip: Fish composition by weight (kg) of trawl net codend (% of traditional).
Catch by Weight (kg)
Rig
TED only
T90
Sq Window
Traditional
Shrimp
2.4
2.0
2.0
2.0
Commercial
20.3
0.5
20.0
12.0
Trash
48.0
5.0
43.0
45.0
Total
70.7
7.5
65.0
59.0

Catch by Weight (% of Traditional)
Rig
TED only
T90
Sq Window
Traditional
Shrimp
120%
100%
100%
2.0
Commercial
169%
4%
166.7%
12.0
Trash
107%
11%
95.6%
45.0
Total
120%
13%
110.2%
59.0

Catch by Category (% of Traditional)
Rig
TED only
T90
Sq Window
Traditional
Shrimp
3%
27%
3.1%
2.0
Commercial
29%
7%
50%
12.0
Trash
68%
67%
13.9%
45.0
Total


2.1%
59.0

Table 2. Second trip: Fish composition by weight (kg) of trawl net codend.
Catch by Weight (kg)
Rig
TED only
T90
Sq Window
Traditional
Shrimp
6.2
11.8
9.8
9.5
Commercial
109.3
125.3
104.0
109.0
Trash
91.0
70.8
112.0
126.3
Total
206.5
207.9
225.8
244.8

After analysis of the tables, the following points were observed and discussed:
· The reduction in the shrimp catch in the TED may relate to a problem of
the way the TED was deployed ­ possibly upside down or more likely as
mentioned under point 4.. More work on this may improve that catch.
· During the retrieval of the gear, the vessel must maintain some forward
speed.
· The square mesh window may require a larger mesh to further reduce the
catch of unwanted fish.

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ICES WGFTFB REPORT 2008
| 257
· The selvedge line that picks up codends should be extended further as in
structed before the trial to compensate for the increased 3 m length in the
TED codend.
· Shortening the length of net and placing the TED further forward may im
prove the stability and reduce any loss of shrimp. However, care should be
exercised to not shorten the net too much particularly if the escape open
ing is faced downward.
2007 ­ 2008 activities in bycatch management
Two National Steering Committee meeting (NSCM) were held this year in Douala (5
April and 8 September 2007. These meetings were reduced to only key members plus
some industrial fishermen because of funding.
The points discussed during the meetings were:
· To prepare the organization of the 4th MCS meeting in Douala;
· To officially discuss the points of collaboration between Cameroon and
Nigeria;
· To inform and sensitize the fishing Companies on the new regulation in
cluding the use of BRDs/TEDs in Cameroon, and to present to them the
need of harmonizing the fisheries laws and regulations in the subregion;
· To discuss on the future of the project knowing that it is ending in June
2008;
· To present the result of the study carried on the survey of the economic
performance indicators of fishing companies;
The National coordinators participated to two MCS meetings organized in Lagos in
March and June 2007. A training workshop on BRDs and TEDs also held in Douala 16
to 21 April 2007. Prototypes have been exhibited to the public, their functioning ex
plained and some fishermen trained on how to build the devices. Practical/ Train
ings/Demonstrations/SeaTrials on TEDs and BRDs have been also organized on
board a commercial vessel in Limbe. Two kinds of BRDs, the Square mesh window
codend and the 90°mesh codend were tested successful, compared to a traditional
codend and to the codend equipped with TED.
The 4th MCS meeting on the Harmonization of Fisheries Laws and Regulations within
the Southern Gulf of Guinea States held in Douala Cameroon, hosted jointly by the
"Caisse de Développement de la pêche maritime" and the Research Centre for Fisher
ies and Oceanography (SRHOLIRAD on 19 to 20 December 2007. It is important to
recall here that the main purpose of these series of MCS meetings is to establish the
framework for the establishment and harmonization of marine fisheries Monitoring,
Control and Surveillance (MCS) procedures and enforcement processes within the
Southern Gulf of Guinea. The aim is to eliminate all forms of unwholesome fishing
practices including Illegal, Unregulated and Unreported (IUU) fishing.
The first three sessions were held in Lagos, while the last one was organized in
Douala Cameroon. A total of twenty four participants attended the meeting. This in
cludes twelve (12) official delegates from Benin, Togo, Nigeria, Gabon, Equatorial
Guinea and Cameroon, ten (10) observers from MINEPIA and IRAD and 2 FAO offi
cers from Yaoundé and Rome. A draft Convention was also discussed. Participants
were committed to carry out the necessary consultations within their States in order
to obtain a national consensus on the draft convention under scrutiny. Member States
also adopted that the same Argos facilities and equipment currently being used by

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ICES WGFTFB REPORT 2008
the countries within the Initiative that already established their VMS for uniformity
and cost effectiveness. A survey of the economic performance indicators of fishing
companies has been carried out in on fishing companies and the results presented
during the MCS workshop held in Douala.
Lessons learned and future activities
Lessons learned
· Necessity for a close cooperation with Nigeria (from the very beginning of
the project and recently on harmonization of fisheries legislation for the
whole region started on the initiatives of the two countries.
· The familiarization with TED and BRDs on Nigerian vessels; There is hope
now that the collaboration with Nigeria for the implementation of the
BRDs and TEDs in the shrimp fishery will help the country organize its
fishery sector.
· The creation of the initiative called the SubRegional Cooperation in Ma
rine Fisheries Monitoring, Control and Surveillance in the Southern Gulf of
Guinea;
· The possibility for Cameroon to export its shrimp products to US. The re
certification of Nigerian fishing products for the US market has naturally
trickled an interest from the fishing Industry in Cameroon to also obtain
the certification and with this ­ an opportunity to benefit from higher
prices on the shrimp products.
Future activities
· Effective introduction and implementation of BRDs and TEDs in the Cam
eroon fisheries industry;
· 12 months BRD and TED experimentation, onboard sampling/Observer
program (data collection using commercial vessels);
· Study on socioeconomic impact of the By­catch trade in Cameroon should
continue particularly data collection and provision of alternative means of
livelihood;
· Training of Trawlerowners/skippers, technical staff and other stake
holders on BRDs and TEDs Devices building, and fishing gear construc
tion.
· Collaboration of Delegates to engender a uniform approach among mem
ber states in the sustainable management of the living marine resources of
the Subregion;
· Organization of the 5th MCS meeting in Gabon. For this purpose FAO
should translate the Draft Convention into French with copies sent to
member countries before the next meeting, for a better understanding and
participation of member countries;
References
Akande, G. 1998. Bycatch Utilization in Nigeria. In: Ivor Clucas (NRI) and Frans Teutscher
(FAO): Report and Proceedings of FAO/DFID Expert Consultation on Bycatch Utilization
in Tropical Fisheries, Beijing, China, 21­28 September1998; pp 241­251.
Alverson, D.L., Freeberg, M.H., Pope, J.G., and Murawski, S.A. 1994. A global assessment of
fisheries bycatch and discards. FAO Fisheries Technical paper, 339, 233.

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Bayagbona, E.O., Sagua, V.O., and Afinowi, M.A. 1971. A survey of the shrimp resources of
Nigeria. Marine Biology, 11 (2): 178­189.
Clucas, I., and Teutscher, F. 1998. Report and Proceedings of FAO/DFID Expert Consultation
on Bycatch Utilization in Tropical Fisheries, Beijing, China, 21­28 September1998; 329p.
Diakite, B. 1998. Bycatch in Marine fisheries in Senegal. In: Ivor Clucas (NRI) and Frans
Teutscher (FAO): Report and Proceedings of FAO/DFID Expert Consultation on Bycatch
Utilization in Tropical Fisheries, Beijing, China, 21­28 September1998; pp 235­239.
Hall, M.A. 1996. On bycatches. Reviews in Fish Biology and Fisheries, 6; 319­352.
Njifonjou, O. 1998a. The Awasha fishing fleet in the Cameroon coastal area: profitability analy
sis of the purse seine unit activity. 1998 IIFET Int. Conf. Proc.
Njifonjou, O. 1998b. Dynamique de l'exploitation dans la pêche artisanale des régions de
Limbe et de Kribi au Cameroun. Thèse de Doctorat , Université de Bretagne Occidentale,
347p.
Njock, J.C., Njifonjou, O. 2004. L'utilisation des captures accessoires de la pêche crevettière au
Cameroun : Rapport de l'atelier international sur la pêche crevettière dans le golfe de Gui
née ; Douala, 12­14 février 04.
Legaspi, S., S.A. 1998. Bycatch Utilization in Philippines. In: Ivor Clucas (NRI) and Frans
Teutscher (FAO): Report and Proceedings of FAO/DFID Expert Consultation on Bycatch
Utilization in Tropical Fisheries, Beijing, China, 21­28 September1998; pp 105­113.

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Document Outline

• Report of the ICES-FAO Working Group on FishTechnology and Fish Behaviour (WGFTFB)
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