Okavango River Basin Technical
Diagnostic Analysis:
Environmental Flow Module
Specialist Report
Country: Namibia
Discipline: Wildlife
K. Roberts
June 2009
EFA Namibia Wildlife
Okavango River Basin Technical
Diagnostic Analysis:
Environmental Flow Module
Specialist Report
Country: Namibia
Discipline: Wildlife
Author: K. Roberts
Date: June 2009
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EFA Namibia Wildlife
EXECUTIVE SUMMARY
The Namibian wildlife assessment is a first attempt at trying to understand the flow related
water needs of wildlife living along the Namibian section of the Okavango River. The EFA
process can then make predictions of the effects on the abundance of river associated
wildlife, of flow pattern changes in the river, caused by a range of development scenarios.
Similar wildlife assessments were made by Angola and Botswana for their river sections.
The river was divided into units of analysis during a EFA team exercise with all three
countries. (Project Report No 2: Delineation of the Okavango Basin).
The two Namibian integrated units of analysis for the assessment were "main channel with
floodplain", which was represented by a site on the floodplain at Kapako 30km to the west of
Rundu; and the "rocky island and braided channel" unit of analysis which was represented
by a site at the Popa Rapids.
The Namibian wetlands associated wildlife that were considered for this assessment of their
water-flow requirements, included vertebrate taxa other than fish and birds (the latter two
groups were assessed separately). In practice, bats were also excluded because of the
lack of water flow related information on this group.
The "Wildlife Indicators" were those species thought to show relationships with water flow
conditions. These later became the main species dependent on particular flow related
habitats. Seven flow related habitats were identified as indicator habitats for wildlife for all
three countries. As similar habitats had different species in the different countries, the main
wildlife species occupying these habitats in each country became the country representative
species for that indicator. Later some of the habitats and their representative species were
combined and five wildlife indicator groups remained.
Wildlife Indicator 1
Name: Main Channel Dwellers. Representative species: Hippo, Crocodile, Otters,
Terrapins. Water Monitor
Water needs: sufficient channel depth and width for daily living space and protection and
concealment during low water flows. Sufficient high water flows are needed to maintain
sand bars, channel islands and floodplain vegetation, papyrus and reed beds. Enough water
depth / flow during low flow season for some islands to remain as islands. Islands used for
nesting reptiles at the end of the dry season. Islands that become joined to the bank during
low flow seasons will have greater resource use and predator pressures e.g. from humans,
livestock, dogs etc. Sufficient water levels are needed to sustain papyrus and reedbeds.
Sufficient periodic high flows are needed for sandbar maintenance. Early high floods can
inundate nests.
Wildlife Indicator 2
Name: Frogs and river snakes,
Representative taxa:- Frogs, Snakes and Musk shrews.
Known water needs: Periodic high floods are needed to scour out floodplain depressions
and annual floods are needed to fill these. Sufficient low season water levels are needed to
maintain backwaters connected to the channel. Other backwaters and floodplain pools
depend on low season river related groundwater levels. Non groundwater-fed pool water
depth should be at least 50cm at the start of the season for frog lifecycles to complete
before pools dry. Water is needed in backwaters and pools to maintain aquatic
invertebrates, fish and frogs which also form the food of many reptiles, especially juveniles.
Low water flow rates in backwaters. Usually wet but reed beds and water-lilies can survive
limited drying-out. Sufficient low flow water levels needed to maintain fringe vegetation.
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EFA Namibia Wildlife
High floods can remove vegetation. Early floods can inundate reptile and small mammal
nests. Sufficient water is needed for direct access to the vegetation i.e. a barren drawdown
zone would be detrimental.
Wildlife Indicator 3
Name :- Middle floodplain grazers.
Representative species: Elephant, Buffalo, Tsesebe, Warthog.
Known water needs: Annual flooding for from two to six months needed to allow for
vegetation growth. Sufficient flood flows needed to provide sand, silts and nutrients. Slow
flooding and slow receding allows for more vegetation growth.
Wildlife Indicator 4
Name:- Outer floodplain grazers
Representative species: Wildebeest, Zebra, Impala, Duiker, Aardvark, Mice
Known water needs: Occasionally flooded grasslands maintained by a flood frequency
sufficient to maintain tree-line. Grasslands are still available during normal flood peaks. On
higher banks river associated groundwater is available all year to maintain riperian forests.
Wildlife Indicator 5
Name: Lower floodplain grazers
Lechwe, Sitatunga, Reedbuck, Waterbuck. Mice.
Known water needs: Primary floodplain habitat needs seasonal flooding for four to six
months to maintain vegetation. Wildlife use flooded areas and denser floodplain vegetation
during dry season for feeding and protection.
Workshops with wildlife experts from all three countries produced response curves for each
indicator for a range of water flow conditions. These data were then fed into the DSS by the
Environmental Flow Assessment consultants and along with data from the other disciplines
will predict the overall environmental effects for a range of future development scenarios.
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EFA Namibia Wildlife
TABLE OF CONTENTS
EXECUTIVE SUMMARY ................................................................................................ 3
LIST OF TABLES ............................................................................................................ 7
LIST OF FIGURES .......................................................................................................... 8
ACKNOWLEDGEMENTS ............................................................................................. 10
INTRODUCTION ........................................................................................................... 11
Background 11
Okavango River Basin EFA Objectives and Work-plan
11
Project objectives ................................................................................................... 11
Layout of this report
12
2.1 Description of the Okavango Basin
13
2. 2 Delineation of the Okavango Basin into Integrated Units of Analysis .................... 14
2.4Discipline-specific description of Namibian sites ...................................................... 21
2.4.1
Site 4: Kapako .......................................................................................... 21
2.4.2
Site 5: Popa Falls ..................................................................................... 22
3. IDENTIFICATION OF INDICATORS AND FLOW CATEGORIES ........................... 23
3.1. Indicators
23
Introduction ............................................................................................................ 23
3.1.2 Indicator list for Wildlife ................................................................................ 23
3.1.3 Brief description and location of indicators - Namibia .................................. 24
3.2 Flow categories river sites
26
LITERATURE REVIEW ................................................................................................. 32
4.1 Introduction Wildlife Indicators
32
4.2
Wildlife Indicator 1 : Channel Dwellers
33
Main characteristics of the habitat ......................................................................... 33
Species dependent on this habitat. ........................................................................ 33
Life cycle attributes of Indicator 1 representative species. .................................... 34
Hippo mate, are born and suckle in water where they also spend the day largely
submerged in groups. They repeatedly use the same locations, returning
after nocturnal foraging trips. They leave the water at night to graze
individually on land. ................................................................................ 34
Links to flow ........................................................................................................... 34
4.3
Wildlife Indicator 2: Frogs and River snakes ........................................... 35
Main characteristics of Indicator habitat ................................................................. 35
Still or low current conditions. Emergent aquatic vegetation provides cover and food.
Backwaters , floodplain pools and emergent vegetation and permanent swamp
dwellers. Channel emergent / floating vegetation stands such as papyrus,
reed beds and, lily-pad beds, along water margins and in backwaters and
side channels provide protection, feeding and breeding sites for many riverine
wildlife species. (Eg, Branch 1988; Broadley 1983; Smithers 1983;, Skinner
and Smithers 1990). ............................................................................... 35
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EFA Namibia Wildlife
Species dependent on this indicator. ..................................................................... 35
Life cycle attributes of Indicator ............................................................................. 36
Juvenile reptiles hunt for food and find protection in backwaters and floodplain pools.
These habitats are the living space of frogs, aquatic invertebrates, birds,
breeding fish and small mammals that also form the food of juvenile and sub-
adult aquatic reptiles. (Eg Leslie 2005, Branch 1988, Broardley 1983) . 36
Musk shrews need semi aquatic vegetation of dense grasses and reed beds Smithers
(1983). C.hirta also occurs away from wetlands Smithers (1983). They are
largely insectivorous but may be carnivorous, for instance feeding on frogs,
and are active at intervals throughout the day and night. They breed all year
apart from the winter months. They nest in thick grass or flood deposited
debris Smithers (1983). .......................................................................... 36
Links to flow ........................................................................................................... 36
4.4
Wildlife Indicator 3: Middle Floodplain grazers ............................................ 36
Information on Namibian Floodplain grazing Species : .......................................... 36
4.5
Wildlife Indicator 4: Outer floodplain grazers .............................................. 37
Main characteristics of Indicator habitat The riparian zone along floodplain and channel
margins and on larger / higher islands. This vegetation zone is occasionally
flooded during very high floods but is normally dependent on river associated
groundwater (Trees) or local rainfall (grasses). Provides non-aquatic and
floodplain wildlife with cover and grazing especially during flood periods when
other floodplain types are inundated. Riparian trees / forest with species
such as Garcinia livingstonei ,Albizia versicolor and Diospyros mespiliformis.
............................................................................................................... 37
4.6Wildlife indicator 5: Lower floodplain grazers ................................................... 37
Main characteristics of Indicator habitat ................................................................. 38
Other species dependent on this indicator habitat. ................................................ 38
4.9 Summary......................................................................................................... 38
DATA COLLECTION AND ANALYSIS ......................................................................... 39
5.1
Methods for data collection and analysis
39
5.2
Results 39
5.3
A summary of present understanding of the predicted responses of all wildlife
indicators to potential changes in the flow regime
40
5.3.1 Indicator 1. Main channel dwellers. (Hippo, Crocodile, Otters) .................... 41
5.3.2 Indicator 2 Frogs and snakes (Frogs snakes and musk shrews)) ............... 42
5.3.3 Indicator Middle Floodplain grazers. ............................................................ 43
5.4 Conclusions
46
6. Flow-response relationships for use in the Okavango EF-DSS ..................................... 47
Aust,P. Research proposal: Conservation of Nile Crocodiles in north-eastern Namibia:
ecology, socioeconomics and sustainable utilization. NNF
52
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EFA Namibia Wildlife
Transboundary Diagnostic Analysis of the Botswana Portion of the Okavango River
Basin: Land Use Planning
Error!
Bookmark not defined.
LIST OF TABLES
Table 1
Location of the eight EFA sites ................ Error! Bookmark not defined.
Table 2
List of indicators for wildlife and those chosen to represent each site ... 24
Table 3
Questions to be addressed at the Knowledge Capture Workshop, per
indicator per site. In all cases, `natural' embraces the full range
of natural variability .................................................................. 30
Table 4
Inundation categories for the Okavango Delta as recognised by the
HOORC inundation model ....................................................... 30
Tables 5.1-5.5 Predicted responses to possible changes in the flow regime of
indicators 1 - 5 in the Okavango River ecosystem .............. 41-46
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EFA Namibia Wildlife
LIST OF FIGURES
Figure 1
Upper Okavango River Basin from sources to the northern end of
the Delta ................................................................................... 13
Figure 2
The Okavango River Basin, showing drainage into the Okavango
Delta and the Makgadikgadi Pans ........................................... 14
Figure 7.1
Three representative years for Site 1: Cuebe River @ Capico,
illustrating the approximate division of the flow regime into four
flow seasons ............................................................................ 28
Figure 7.2
Three representative years for Site 2: Cubango River @ Mucindi,
illustrating the approximate division of the flow regime into four
flow seasons ............................................................................ 28
Figure 7.3
Three representative years for Site 3 Cuito River @ Cuito
Cuanavale, illustrating the approximate division of the flow
regime into four flow seasons .................................................. 29
Figure 7.4
Three representative years for Site 4: Okavango River @ Kapoko
(hydrological data from Rundu), illustrating the approximate
division of the flow regime into four flow seasons .................... 29
Figure 7.5
Three representative years for Site 5: Okavango River @ Popa
(hydrological data from Mukwe), illustrating the approximate
division of the flow regime into four flow seasons .................... 30
APPENDIX 1: Figure 1: Kapako study site in the dry season showing position of small
mammal traplines sites 1 and 2 and and bases for general
examinations of the floodplains for wildlife sites 3 (dry season)
and 4 (wet season). ................................................................. 53
APPENDIX 2: Figure 2: Wildlife study sites at Popa Falls in the dry season showing the
position of small mammal traplines on both banks and on the
vegetated island. ...................................................................... 54
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EFA Namibia Wildlife
ABBREVIATIONS
ABBREVIATION
MEANING
DTM
Digital Terrain Model
NNF
Namibia Nature Foundation
MET
Ministry of Environment and Tourism
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EFA Namibia Wildlife
ACKNOWLEDGEMENTS
Thanks to Shirley Bethune, Polytechnic of Namibia and Joshua Ndeliimona - Intern
Polytechnic of Namibia, for help with the boat and trapping and Celeste Espach from the
Ministry of Agriculture, Water and Forestry for the site maps.
Mark Paxton is thanked for the great Spotted-necked Otter and snake photographs.
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EFA Namibia Wildlife
INTRODUCTION
Background
An Environmental Protection and Sustainable Management of the Okavango River Basin
(EPSMO) Project is being implemented under the auspices of the Food and Agriculture
Organization of the United Nations (UN-FAO). One of the activities is to complete a
transboundary diagnostic assessment (TDA) for the purpose of developing a Strategic Action
Plan for the basin. The TDA is an analysis of current and future possible causes of
transboundary issues between the three countries of the basin: Angola, Namibia and
Botswana. The Okavango Basin Steering Committee (OBSC) of the Okavango River Basin
Water Commission (OKACOM) noted during a March 2008 meeting in Windhoek, Namibia,
that future transboundary issues within the Okavango River basin are likely to occur due to
developments that would modify flow regimes. The OBSC also noted that there was
inadequate information about the physico-chemical, ecological and socio-economic effects of
such possible developments. OBSC recommended at this meeting that a preliminary
Environmental Flow Assessment (EFA) be carried out to predict possible development-driven
changes in the flow regime of the Okavango River system, the related ecosystem changes,
and the consequent impacts on people using the river's resources.
This preliminary EFA is a joint project of EPSMO and the Biokavango Project. One
component of the preliminary EFA is a series of country-specific specialist studies, of which
this is the Wildlife Report for Namibia.
Okavango River Basin EFA Objectives and Work-plan
Project objectives
The goals of the preliminary EFA are:
To summarize all relevant information on the Okavango River system and its users, and
collect new data as appropriate within the constraints of this preliminary EFA
to use these to provide scenarios of possible development pathways into the future for
consideration by decision makers, enabling them to discuss and negotiate on sustainable
development of the Okavango River Basin;
to include in each scenario the major positive and negative ecological, resource-economic
and social impacts of the relevant developments;
to complete this suite of activities as a preliminary EFA, due to time constraints, as input to
the TDA and to a future comprehensive EFA.
The specific objectives at a preliminary level are:
to ascertain at different points along the Okavango River system, including the Delta, the
existing relationships between the flow regime and the ecological nature and functioning of
the river ecosystem;
to ascertain the existing relationships between the river ecosystem and peoples' livelihoods;
to predict possible development-driven changes to the flow regime and thus to the river
ecosystem;
to predict the impacts of such river ecosystem changes on people's livelihoods.
To use these preliminary EFA outputs to enhance biodiversity management of the Delta.
To develop skills for conducting EFAs in Angola, Botswana, and Namibia.
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EFA Namibia Wildlife
Layout of this report
Chapter 1 gives a brief introduction, to the background of the project and lists project
objectives. Chapter 2 describes the broad study area of the Okavango River Basin and
gives more detail on the two specific sites chosen for this preliminary EFA within the
Namibian section of the river- Kapako floodplain and Popa rapids. In Chapter 3, the agreed
wildlife indicators and flow categories are highlighted. Literature review pertinent to wildlife
work in the Okavango River and other similar systems is given in Chapter 4; full indicators
are listed. The field survey work undertaken for the wildlife investigation within Namibia in
both the dry season (October 2008) and wet season (February 2009); together with data
collection, and results are outlined in Chapter 5. Chapter 6 is a first attempt to link wildlife to
water flows and to provide information on the flow-response relationships for use in the
Okavango EF-DSS. References are found in Chapter 7 and the appendix gives site maps
and a species list.
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EFA Namibia Wildlife
2 STUDY AREA
2.1 Description of the Okavango Basin
The Okavango River Basin consists of the areas drained by the Cubango, Cutato, Cuchi,
Cuelei, Cuebe, and Cuito rivers in Angola, the Okavango River in Namibia and Botswana,
and the Okavango Delta (Error! Reference source not found.). This basin topographically
includes the inactive drainage are of the Omatako Omuramba. Although this ephemeral river
still regularly floods along its southern portion, it has not contributed any flow to the
Okavango River. Outflows from the Okavango Delta are drained through the Thamalakane
and then Boteti Rivers, the latter eventually joining the Makgadikgadi Pans. The Nata River,
which drains the western part of Zimbabwe, also joins the Makgadikgadi Pans. On the basis
of topography, the Okavango River Basin thus includes the Makgadikgadi Pans and Nata
River Basin (Error! Reference source not found.). This study, however, focuses on the
active drainage parts of the basin in Angola and Namibia, and the Okavango delta in
Botswana. The Omatako Omuramba, Makgadikgadi Pans and Nata River are not included.
Upper Okavango River Basin
N
W
E
S
C
u
tato
Cu
#
c
h
i
#
C
C
u
u
#
it
a
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Menongue
ba
u
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g
h
#
Major settlement
o
i
# Cuito Cuanavale
River
C
#
ue
Fossil river
be
C
Panhandle
ANGOLA
uiri
Permanent swamps
ri
#
Seasonal swamps
Cubango
Cuito
NAMIBIA
Okavango
#
Rundu
#
#
#
0
300 Kilometers
#
Figure 1
Upper Okavango River Basin from sources to the northern end of the Delta
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EFA Namibia Wildlife
Okavango River Basin
N
W
E
S
Cu
t
a
Cu
#
t
o
c
hi
#
C
C
ui
ua
#
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# Cuebe
C
ANGOLA
uirir
#
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Cubango
Cuito
NAMIBIA
Okavango
#
Rundu
#
# #
#
##
#
#
#
Maun
#
Makgadikgadi Pans
# Ghanzi
#
Major settlement
River
Fossil river
Panhandle
0
600 Kilometers
Permanent swamps
Seasonal swamps
Figure 2
The Okavango River Basin, showing drainage into the Okavango Delta and the
Makgadikgadi Pans
2. 2 Delineation of the Okavango Basin into Integrated Units of Analysis
Within the Okavango River Basin, no study could address every kilometre stretch of the river,
or every person living within the area, particularly a pilot study such as this one. These
representative areas that are reasonably homogeneous in their ecological characteristics and
can be delineated and used to choose several sites in which focus for data-collection and
monitoring can be done. The results from each representative site can then be extrapolated
over the respective wider areas.
Using this approach, the Basin was delineated into Integrated Units of Analysis
(EPSMO/Biokavango Report Number 2; Delineation Report) by:
dividing the river into relatively homogeneous longitudinal zones in terms of:
hydrology;
geomorphology;
water chemistry;
fish;
aquatic macroinvertebrates;
vegetation;
wildlife
harmonizing the results from each discipline into one set of biophysical river zones;
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EFA Namibia Wildlife
dividing the basin into relatively homogeneous areas in terms of social systems;
harmonizing the biophysical river zones and the social areas into one set of Integrated Units
of Analysis (IUAs). See delineation report for details
The 19 recognised IUAs were then considered by each national team as candidates for the
location of the allocated number of study sites:
Angola: three
sites
Namibia: two
sites
Botswana: three
sites.
The sites chosen by the national teams are given in Error! Reference source not found..
Table 1
Location of the eight EFA sites
EFA Site No
Country
River
Location
1 Angola
Cuebe
Capico
2 Angola
Cubango
Mucundi
3 Angola
Cuito Cuito
Cuanavale
4 Namibia
Okavango
Kapako
5 Namibia
Okavango
Popa
Rapids
Upper Panhandle
6 Botswana
Okavango
around Shakawe
Xakanaka lagoon
7 Botswana
Xakanaka in Delta
and Khwai River
8
Botswana
Boteti Rivers
Maun and Chanoga
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EFA Namibia Wildlife
2.3
Overview of sites
In the Namibian section of the Okavango River, the majority of the human population lives
along the river and the main road, with several hot spots such as Rundu, Divundu and
Nkurenkuru which have a high population density. The river can be divided into four clear
units of analysis, the longest section that extends from where the river enters Namibia at
Katwitwi to the Cuito confluence that is typified by the meandering mainstream and large
seasonally-flooded floodplains on either side to the river (Kapako site 4, was chosen as a
typical floodplain and mainstream site within this section); the section immediately
downstream of the Cuito confluence that has permanently swamped areas and large islands
(not included in the preliminary survey but essential to include in a later more detailed EFA
study); the southward flowing rocky, braided section from Mukwe to just below the Popa
Rapids where the river is largely confined to the mainstream and flows around several sand
and rock based islands (Popa rapids Site 5, was chosen as a typical rocky river site within
this section) and the protected section of the river downstream of Popa to the border with
Botswana at Mohembo that lies within the newly declared Bwabwata National Park which as
two of its core conservation areas on either side of the river, the Buffalo core area on the
west bank and the Muhango core area on the east bank.
2.3.1
Site 4: Kapako
The main focus point for socio-economic work at the Kapako floodplain site 4 is Kapako
village: S-17.94 E 19.56, situated some distance inland from the river on the other side of
the main road.
Figure 3. Site 4: Kapako showing the village of Kapako, the surrounding town and the position of
the main road and the villages in relation to the river. Most of the area between the road and the river
is floodplain. The border shows the area covered by the socio-economics team. Map by Socio-
economics team.
The main villages close to Kapako village are Mupini to the east (downstream), Mukundu to
the south, Ruugua and Sinzogoro to the weat (upstream).
The floodplain site itself is situated on the Okavango River and three main sites on the
floodplain and the mainstream were used for sampling. They were:
Kapako site 1 S-17.87775 E- 19.58200 (south bank) S- 17.87850 E-19.58211 (end of site 1)
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EFA Namibia Wildlife
Kapako site 2 S- 17.86557 E-19.58057 Kapako site 3 S- 17.86209 E-19.57855
Figure 4. shows two satellite images of the Kapako floodplain site 4, one in the dry season and one in
the wet or flood season. Maps by Celeste Espach.
The riverine landscape includes the main Okavango River channel or mainstream, the
annually flooded floodplains with several braided side channels and deeper pools or
backwaters, as well as the higher fluvial terrace with alluvial deposits are very seldom
flooded. There is a steep, well vegetated bank at the edge of the floodplain close to the main
road that rises to several meters above the floodplain.
Kapako area has a population of approximately 2,500 people within 10 km of Kapako village.
The greatest density of people (over 100 per km2 ) live alongside the river in the area just
west of the Kapako study site whilst at the site itself the density varies from no people on the
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EFA Namibia Wildlife
floodplain, 6 25 / km2 at the Ebenezer mission, to a density of 25 50 /km2 closer to the
road and 51 100 /km2 on the other side of the main road, rapidly decreasing again with
distance inland. (See Map 3 in Populations Demographics Report prepared by Celeste
Espach). We can assume that some of these people make some use of the floodplain site at
Kapako and elsewhere along this stretch of river.
During the focus group discussion held at Kapako village, the basin residents mentioned
that, the flooding starts when the rising river and channel waters push out over flat
surrounding ground and the biggest floodplains form in years when river levels are highest.
They said that the most important feature of the flooded areas is that they are rich in
nutrients. The floodplains also offer the young fish refuge from larger, predatory species and
thus offer the greatest survival of young fish. They had noted that an overall increase in fish
population occurs in years when water levels are high and flooding lasts longest. Local
people have recognised that water quality and fish resources are decreasing in the
Okavango River. Fish and fishing remain significant features in the lives of people at
Kapako, who fish for food or to earn incomes by selling their catches. In addition some earn
money by providing trips for tourists. They estimate fish stocks in the floodplains to be four
times higher than in the main channel.
About 47% of households at Kapako catch fish, and each person consumes an average of
10-20 kilograms of fish per year. September to December is the peak fishing period at
Kapako when the river is at its lowest and fish are concentrated in the mainstream. The
kinds of traps or gear used to catch fish are separated into traditional and modern methods.
The most used traditional gear are fish funnels, kraal traps, scoop baskets, push baskets,
bows and arrows, set fish hooks and spears.
Modern gear consists of line and hooks, wire mesh fykes, illegal mosquito nets, and gill and
seine nets. The use of fish for recreational angling forms part of the tourism value associated
with the river. Biophysical response curves for the angling species would feed into the
tourism values for the river reducing them partially. Only a small part of tourism value is
attributable to angling.
At Kapako, as elsewhere along the Namibian section of the river, the ever -increasing human
population and clearing for crops and livestock has put increasing pressure on the natural
resources along the main channel. The vegetation along the river bank is overgrazed and in
some areas depleted, thus at Kapako the residents graze their livestock across the river on
the Angolan floodplain. Cattle were routinely seen being swam across the river at this site
during fieldwork.
Associated with this population growth, has been an increase in livestock, fire frequency as
well as the area of land cleared for crops and fuel. These associated land use changes are
an undeniable factor of increasing settlement and development at a Kapako and indeed all
along the Okavango.
The road westwards from Rundu has been upgraded and is currently being tarred. It runs
parallel to the Okavango River all the way to the border post with Angola at Katwitwi.
This has opened up the region allowing people to exploit the land alongside the road. As
expected highest densities are alongside the road parallel to the river. As the population
continues to increase, exploitation of the land that new roads have opened up should
disperse the pressure on the Okavango River floodplains and its resources to land further
inland from the river, although the river will always remain the main source of water even for
livestock watering.
The extent of erosion and clearing and thus of bare ground has also increased; yet the
people perceive the overall water quality not to have declined substantially. The only
exceptions mentioned were an increase in phosphate concentrations, a decrease in water
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EFA Namibia Wildlife
clarity and a related increase in suspended sediments. There are more short term, seasonal
variations in water quality particularly in the floodplain pools, than any long term water quality
change. So far there does not seem to have been an excessive exploitation of the water
resources in the main channel, although the basin further inland has some serious water
shortages at times and a lack of deep boreholes. The Kalahari sands that overlay the area
are deep.
2.3.2 Site 5: Popa rapids
The main focus for the socio-economic work at the Popa rapids Site 5 was the village of
Popa and the Popa Falls Rest Camp run by Namibia Wildlife Resorts. The main transect
used for the physical and biological field survey work was a transect across the river
immediately above the Popa Rapids from the irrigation water drawoff point used by the
Prison Services on the eastern ban (West Caprivi) where the gauge plate was put up to the
protected section close to the Popa Falls Rest Camp on the western bank. Popa rapids: S-
18.15316 E- 21.6045 (Popa Falls rest camp)
Popa falls (gauge plate) S- 18.11603 E- 21.57900. Figure 5. below shows the main villages.
Figure 5. Site two, Popa rapids is shown in the map above; The majority of population lives
along the river and the main road. Map from the socio-economic team.
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EFA Namibia Wildlife
Figure 6. below shows the Popa rapids site five in both the dry and the wet season and
indicates the main field survey transect and team sampling sites. The Wildlife survey maps
are shown in the appendix.
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EFA Namibia Wildlife
Figure 6. Satellite images of the wet and dry season for Popa rapids here showing transect
and sampling sites. Maps prepared by Celeste Espach.
About 3,000 people live in the area surrounding Popa. The highest population density in the
area is immediately upstream of the Popa rapids at the Bagani/Divundu settlement, within an
area of over 12 km2 . At the Popa rapids site itself the population density is much lower at 6
25 people/km2 and it must be remembered that the Popa camp is within an 8 km2 park, the
islands are uninhabited and the opposite bank supports a community campsite reserved for
tourists. Immediately downstream of Popa camp the riverside population increases to 26-50
people/km2 and includes several lodges. See Map 3 in the Population Demographics report
prepared by Celeste Espach for the TDA.
At the Popa rapids, the entire width of the river cascades down several meters before
resuming its normal slow and leisurely flow. The quartzite rocks were formed from sediments
deposited in rift valleys about 900 million years ago, (el Obeid, S., Mendelsohn 2004).
During the focus group discussion, it was mentioned that due to the Popa rapids and rocky
areas, it's difficult for the local fishermen to catch fish as desired. Therefore, only a few
individuals that own local mukoros, hook and line, and gill fish nets have access to fish
catches in the main channel. Thus fishing is a secondary activity for most people at the
Popa area, contributing little to the overall cash or in-kind incomes of the majority of
households. People also pay much less attention to fishing than to farming and business
activities. Each household depends on a different mix of incomes derives from wages,
business earnings, pensions and remittances
Papyrus cyperus, papyrus, dominates the deepest water margins alongside the main
channels. Water can seep through the walls of papyrus to the reedbeds behind the papyrus
and in places where they exits into backwaters and side channels. The sandy sediments are
confined to the channels. These are flanked by reed beds of Phragmites, Typha capensis or
bulrushes and the sedge Miscanthus junceus in the shallower waters. The residents do not
experience floods as there are no floodplains in this area. They depend in the main channel
for most of their water and wetland resources. Most houses at Popa village are thatched with
grass and reeds, while reeds are used extensively to make sleeping mats, walls, palisades,
courtyards and fences.
Farming activity is an important source of income; households are engaged in both crop and
livestock farming. Planting is staggered through the raining reason and is initiated only after a
good rainfall event. This increases the chance of crop survival during the hot dry periods.
Livestock farming is dominated by cattle and goats, not kept within fields but are moved for
grazing and between water sources, mainly the Okavango River.
Tourism is a major source of income to the Popa resident; most of them are employed within
the lodges around the Popa area. They value tourism as their major source of income.
2.4 Discipline-specific description of Namibian sites
2.4.1 Site 4: Kapako
The Namibian, "main channel with floodplain ecosystem", representative of this integrated
unit of analysis was the floodplain at Kapako that is located 30km to the west of Rundu
Town. The site consists of a meandering main river channel that forms a loop to the north.
Inside the loop on the Namibian side and the west side in Angola there are floodplains
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EFA Namibia Wildlife
formed by previous progressive meanders of the river. These consist of a series of banks of
different heights interspersed with level areas and depressions. On the southern edge of the
floodplain there is a riparian fringe or dry-bank. The site has varied vegetation that is
associated with the large range of geomorphological features of the main channel, river
bank, floodplain and dry bank. The characteristics of the vegetation in any particular location
depend on the water inundation periodicity during present and historic flood and dry seasonal
cycles. (See the Vegetation report and Appendix A for a site image) The varied vegetation
of the site provides a range of habitats for wildlife for most parts of the year. These are the
main channel fringe vegetation, primary (lower) floodplain vegetation, secondary (middle),
floodplain vegetation, tertiary (Upper) floodplain (tree islands and bank). During all but small
floods most habitats apart from the upper floodplains, tree islands and riparian zone are
inundated and this restricts the available living space for terrestrial wildlife. During high
floods only the dry bank and emergent trees remain unsubmerged. Human pressures have
reduced the wildlife component of the floodplains in this unit. The larger grazing mammals no
longer occur in the unit except Hippo and possibly Duiker because all have been hunted to
local extinction. The flood season alternative habitats normally used by wetland wildlife i.e.
the riperian zone and inland forest savanna is now largely used for stock-grazing or
farmland.
2.4.2 Site 5: Popa Falls
The Namibian "rocky island and braided channel" unit of analysis was represented by a site
at the Popa Rapids. The site consists of deep channels contained within rocky, riparian tree
covered banks. The channel has vegetated islands and a bedrock bar that crosses the river
width resulting in many small bedrock rapids with a fall of between two and three meters.
Because there are no floodplains at this site and the river is confined, the vegetation and
terrestrial wetland wildlife habitats vary over short distances that reflect the different water
levels of the annual flood cycle. For instance the downstream edges of the islands often
have circling fringes of Papyrus, Reeds and Sedges that form 2-20m wide bands parallel to
the water. The larger island interiors consist of riparian forest. Downstream of the rapids
there are sandbars and further small reed-fringed islands.
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3. IDENTIFICATION OF INDICATORS AND FLOW CATEGORIES
3.1. Indicators
Introduction
Biophysical indicators are discipline-specific attributes of the river system that respond to a
change in river flow by changing their:
abundance;
concentration; or
extent (area).
Social indicators are attributes of the social structures linked to the river that respond to
changes in the availability of riverine resources (as described by the biophysical indicators).
The indicators are used to characterise the current situation and changes that could occur
with development-driven flow changes.
Within any one biophysical discipline, key attributes can be grouped if they are expected to
respond in the same way to the flow regime of the river. By example, fish species that all
move on to floodplains at about the same time and for the same kinds of breeding or feeding
reasons could be grouped as Fish Guild X.
3.1.2 Indicator list for Wildlife
In order to cover the major characteristics of the river system and its users many indicators
may be deemed necessary. For any one EF site, however, the number of indicators is
limited to ten (or fewer) in order to make the process manageable. The list of indicators was
developed collaboratively by the country representatives for the discipline (for the wildlife
component these were Mr. Kevin Roberts Namibia, Dr. Carmen Van-Dúnem Angola, and
Dr. Casper Bonyongo Botswana). The representative species are given in Appendix B and
discussed fully in Chapter 0.
The "Wildlife Indicators" were those species thought to show relationships with water flow
conditions. These later became the main species dependent on particular flow related
habitats. Seven flow related habitats were identified as indicator habitats for wildlife for all
three countries. As similar habitats had different species in the different countries, the main
wildlife species occupying these habitats in each country became the country representative
species for that indicator. Because some species depended on more than one habitat some
of the habitats and their representative species were combined so as to make the indicator
species groups unique. Five wildlife/habitat indicator groups were finally used to assess
responses to changing water flow conditions in the river.
The Wildlife that were considered for the wildlife assessment included vertebrate taxa other
than fish and birds which were assessed separately. In practice, bats were excluded
because of the lack of flow related information.
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EFA Namibia Wildlife
Table 2
List of indicators for Namibian wildlife and those chosen to represent each site
Indicator
Indicator name and representative
Sites represented
Number
species
1 2 3 4 5 6 7 8
x x
Channel Dwellers .
1
Including Channel island, sand and rock
bar dwellers. Hippo, Crocodile. Water
Monitor, Otters, Terrapins
Frogs and river snakes. Backwater ,
x
floodplain pool emergent vegetation
2
and permanent swamp dwellers.
Snakes, Frogs, Musk Shrews
Middle Floodplain grazers Secondary
x
seasonally flooded floodplain
3
dependant species Elephant, buffalo,
Tsesebe, Warthog
Outer floodplain grazers
x x
Tertiary floodplain channel riparian
zone and Delta island grassland
4
dependant species.
Wildebeest, Zebra, Impala, Duiker,
Aardvark, mice.
Lower floodplain grazers
x
Primary seasonally flooded floodplain
dependant species,
5
Lechwe,
Sitatunga,
Reedbuck,
Waterbuck,
,
3.1.3 Brief description and location of indicators - Namibia
Wildlife Indicator 1
Name: Channel Dwellers
Description: Main channel dwellers. These species need sufficient low flow channel width
and depth for daily living space, for protection from disturbance and to obtain food. Includes
24
EFA Namibia Wildlife
vegetated islands and sand bars in main channel, that provide protection, feeding and
breeding sites.
Representative species: Hippo, Crocodile. Otters. Water Monitor, Terrapins.
Flow-related location: Main channel and pools during low flow periods and channel sandbars
and upstream and downstream of islands during higher flows.
Water needs: >1.5m depth and >80m channel width for protection and concealment during
low flow. Sufficient high flows to maintain sand bars, floodplain vegetation and papyrus and
reed beds.
Vegetated islands and sand bars in main channel need enough water depth / flow during low
flow season for some islands to remain as islands. Islands used for nesting for reptiles at the
end of the dry season. Islands that become bank will have greater resource use and predator
pressures e.g. from humans, livestock, dogs etc. Need sufficient periodic high flows for
sandbar maintenance. Early high floods can inundate nests.
Wildlife Indicator 2
Name: Frogs and river snakes
Description: Backwaters and floodplain pools used for protection, feeding and breeding sites.
Includes emergent vegetation and permanent swamp.
Representative species:
Frogs, snakes, Musk shrews
Flow-related location: After floodplain inundation recedes, floodplain depressions and
backwater pools remain filled. Water levels reduce during the following dry season until the
next flood. Pools and backwaters are characterized by still water or slow currents with
emergent and floating vegetation such as water lilies. Some pools are dependent on river
related groundwater during the dry season and remain wet all year. Backwaters have low
currents and emergent and floating vegetation but are linked to the river for part or most of
the year. Vegetation along water margins and in backwaters and side channels provide
protection, feeding and breeding sites for many riverine wildlife species.
Known water needs: Periodic floods to scour out and annual floods to fill the floodplain
depressions. Floodplain groundwater levels above pool floors. Non groundwater-fed pool
water depth at least 50cm at start of dry season for frog lifecycles to complete.
Sufficient dry season water levels for backwaters.
Usually wet but reed beds and water-lilies can survive limited drying-out. Sufficient low flow
water levels are needed to maintain fringe vegetation.
Wildlife Indicator 3
Name: Middle floodplain grazers.
Description: Floodplain areas that flood later and are inundated only over the flood peak.
Normally un-inundated and the vegetation is available to terrestrial wildlife for longer during
normal floods except during flood peaks.
Representative species:, Elephant, buffalo, Tsesebe, Warthog
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EFA Namibia Wildlife
Flow-related location: Secondary floodplain areas (higher lying) and banks along main
channel and margins to smaller islands.
Known water needs: Flooding during high-flow season for two to six months.
Wildlife Indicator 4
Name: Outer floodplain grazers.
Description: Grasslands and riparian zone along floodplain and channel margins and on
larger / higher islands. This vegetation zone is occasionally flooded during very high floods
but is normally dependent on river associated groundwater (Trees) or local rainfall (grasses).
Provides non-aquatic and floodplain wildlife with cover and food especially during high flows.
Representative species:
Wildebeest, Zebra, Impala, Duiker, Aardvark, Mice
Flow-related location: Riverine margins and islands only occasionally flooded.
Known water needs: Periodic flooding needed to maintain floodplain margin tree-lines.
River associated groundwater is available all year to maintain riparian forests. Grazing areas
important for wildlife during and after floods.
Wildlife Indicator 5
Name: Lower floodplain grazers
Description: Seasonally inundated channel floodplains and seasonal swamps. New
vegetation available during and after inundation. Floodplain pools and backwaters filled.
Representative species: Lechwe, Sitatunga, Reedbuck, Waterbuck,
Flow-related location: Primary floodplains along margins of main river channel and
backwaters.
Known water needs: Annual flooding for four to six months over flood period. Sufficient flood
flows needed to provide sand, silts and nutrients and duration for vegetation growth. Slow
flooding and slow receding allows for more vegetation growth. These wildlife species use the
inundated floodplains for feeding and protection from predators.
3.2 Flow categories river sites
One of the main assumptions underlying the EF process to be used in the TDA is that it is
possible to identify parts of the flow regime that are ecologically relevant in different ways
and to describe their nature using the historical hydrological record. Thus, one of the first
steps in the EFA process, for any river, is to consult with local river ecologists to identify
these ecologically most important flow categories. This process was followed at the
Preparation Workshop in September 2008 and four flow categories were agreed on for the
Okavango Basin river sites:
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EFA Namibia Wildlife
Dry season
Transitional Season 1
Flood Season
Transitional Season 2.
Tentative seasonal divisions for river Sites 1-5 are shown in Figure 7.1 to Figure 7.5. These
seasonal divisions will be formalised by the project hydrological team in the form of
hydrological rules in the hydrological model. In the interim they provide useful insights into
the flow regime of the river system suggesting a higher within-year flow variability of the
Cuebe River and a higher year-on-year variability of the Cubango River.
It is planned to use similar flow seasons for the remaining river sites: 6 and 8.
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EFA Namibia Wildlife
120
Wet
100
Trans 1
Trans 2
Dry
80
Year 2
r
60
Year 1
r
Year 3
r
40
20
0
O
N
D
J
D
F
M
A
M
J
J
M
J
A
S
Figure 7.1 Three representative years for Site 1: Cuebe River @ Capico, illustrating the
approximate division of the flow regime into four flow seasons
1200
Wet
1000
Trans 1
Trans
n 2
Dry
800
Year
Y
1
600
Year
Y
2
Year
Y
3
400
200
0
O
N
D
J
D
F
M
A
M
J
J
M
J
A
S
Figure 7.2 Three representative years for Site 2: Cubango River @ Mucindi, illustrating the
approximate division of the flow regime into four flow seasons
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EFA Namibia Wildlife
250
Wet
Dry
200
Trans 1
Trans 2
150
Year 1
ear
Year 2
ear
100
Year 3
ear
50
0
O
N
D
J
F
M
A
M
J
J
M
J
A
S
Figure 7.3 Three representative years for Site 3 Cuito River @ Cuito Cuanavale, illustrating
the approximate division of the flow regime into four flow seasons
1000
900
Wet
We
800
Dry
Dr
Tr
T ans
r
1
ans
Tra
Tr n
a s
n 2
s
Dry
Dr
700
600
Year 1
500
Year 2
400
Year 3
300
200
100
0
O
N
D
J
F
M
A
M
J
J
M
J
A
S
Figure 7.4 Three representative years for Site 4: Okavango River @ Kapoko (hydrological data
from Rundu), illustrating the approximate division of the flow regime into four flow
seasons
1800
1600
Wet
1400
Dry
Trans 1
Trans 2
n
Dry
1200
1000
Year 3
0
Year 2
800
Year 1
600
400
200
0
O
N
D
J
F
M
A
M
J
J
M
J
A
S
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EFA Namibia Wildlife
Figure 7.5 Three representative years for Site 5: Okavango River @ Popa (hydrological data
from Mukwe), illustrating the approximate division of the flow regime into four flow
seasons
The literature review (Chapter 0) and data collection (Chapter 0) are focused on addressing
what is initially expected to be nine main questions related to these flow seasons (Table ).
Table 3
Questions to be addressed at the Knowledge Capture Workshop, per indicator per
site. In all cases, `natural' embraces the full range of natural variability
Question
Season
Response of indicator if:
number
1
Onset is earlier or later than natural mode/average
2
Dry Season
Water levels are higher or lower than natural mode/average
3
Extends longer than natural mode/average
Duration is longer or shorter than natural mode/average - i.e. hydrograph is
4
Transition 1
steeper or shallower
5
Flows are more or less variable than natural mode/average and range
Onset is earlier or later than natural mode/average synchronisation with rain
6
Flood season
may be changed
7
Natural proportion of different types of flood year changed
8
Onset is earlier or later than natural mode/average
Transition 2
Duration is longer or shorter than natural mode/average i.e. hydrograph is
9
steeper or shallower
3.3 Inundation categories delta sites
The recognised river flow categories are not relevant in the Delta, where inundation is the
major driver of ecosystem form and functioning. The main inundation categories recognised
by the inundation model developed by the Harry Oppenheimer Okavango Research Centre
(HOORC) are used here (Table 4). These categories do not apply to the Namibian sites but
the table is included for completeness.
Table 4
Inundation categories for the Okavango Delta as recognised by the HOORC
inundation model
Inundation category number Inundation category name
Delta 1
Channel in permanent swamp
Delta 2
Lagoons in permanent swamp
Delta 3
Backswamp in permanent swamp
Delta 4
Seasonal pools in seasonally flooded zones
Delta 5
Seasonal sedgelands in seasonally flooded zones
Delta 6
Seasonal grasslands in seasonally flooded zones
Delta 7
Savannah dried floodplain in seasonally flooded zones
Boteti 1
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Boteti 2
Disconnected pools
Boteti 3
Dry
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LITERATURE REVIEW
4.1 Introduction Wildlife Indicators
The review concentrates on the representative wildlife species for the flow related indicators
(Table 3.)
The first unit of analysis In Namibia (represented by site 4), Main channel with floodplains,
has few protected areas on the Namibian bank and an increasing human population. The
Angolan bank was largely uninhabited between 1966 and 2002 due to war. Since Namibian
independence and especially since 2002 when civil war ended in Angola, some people have
returned but landmines remain a restraint to development on the northern bank of the river.
(Mendelsohn and el Obeid 2004). The resources of the northern river bank in Angola, such
as reeds and grazing are often used by Namibians when the Namibian side becomes
depleted.
In Namibia, clearing natural vegetation for subsistence agriculture and livestock production
as well as government irrigation schemes are the chief land uses. The river is seen by some
in government as providing water that can be used for irrigation or other use elsewhere in
Namibia, and by the people as providing free water, reeds, fish and livestock grazing areas
(Mendelsohn and el Obeid 2004). Because of the above pressures, few of the larger natural
floodplain associated mammals now remain in this unit (van Aarde and Ferreira 1997).
In contrast, the conservation of natural habitats is also being promoted by some government
departments and NGOs that support the establishment of conservancies and protected areas
of different types in the region. Some of the floodplain species, Lechwe, reedbuck and
waterbuck, could potentially be reintroduced into existing or new conservancies if there is
continued support for this type of land use in the future. The Namibian populations of these
species are low and declining but there are long term management plans to increase them
and reintroduce them into suitable areas in Caprivi and Okavango (Martin 2004).
The smaller wildlife taxa in this unit are also threatened by increasing human pressure on the
river resources but can still be found associated with the river margins and floodplains
because here human habitation and land clearing for agriculture is prevented or reduced by
regular flooding. Literature on the wildlife of this unit was chiefly from general Namibian
wetland research eg Simmons, Brown and Griffin (1991), Namibian species occurrence lists
such as in Bethune (1990), Curtis et al (1998), Griffin and Grobler (1991), Griffin (2003),
Griffin and Coetzee (2005), as well as distribution maps and species descriptions from
Southern African wildlife books eg Mammals: Smithers (1983), Apps (2000), Reptiles:
Branch (1988), Rodents: De Graff (1981), Snakes: Broadly (1983), Bats: Taylor (2000), and
Frogs: Carruthers (2001)., Specialist reports contained in environmental impact studies were
another source of information. e.g. van Aarde and Ferreira (1997) and Jacobsen (1997).
The second Namibian unit of analysis (represented by site 5) is characterized by channel
islands and rapids. It includes the protected areas of the western core conservation areas of
Bwabwata National Park, (Popa Falls, Mahangu and Buffalo). Apart from the above
literature, information on the wildlife in this unit includes Namibian literature associated with
the management of these protected areas, such as aerial surveys and game counts (eg
Brown, Stander, Meyer-Rust, and Mayes, 2005; Chase, 2007; Rodwell, Tagg and Grobler,
1995). Reports produced during the environmental assessment of a proposed hydroelectric
scheme near Popa Rapids (eg Griffin, 2003; Bethune, 2003) were another source of
information of the river-associated wildlife occurring in this unit. Good details and excellent
32
EFA Namibia Wildlife
accounts of the Namibian distributions, biology and aspects of management of several larger
wetland associated mammals are available, (e.g. Martin 2004), as part of the transboundary
mammal project of MET which was facilitated by the Namibia Nature Foundation (NNF) and
is available on their website. The information was also made available as a series of booklets
on:- Southern Savanna Buffalo, Savanna Elephant, Hippopotamus, Roan, Sable and
Tsessebe and Southern Reedbuck, Common Waterbuck, Red Lechwe and Puku. E.g. Martin
(2008).
Web based searches for particular taxa and Okavango River usually produced references to
literature on the wildlife of the Okavango Delta system in Botswana. These were useful for
habitat use and lifecycle information on particular species such as Crocodile (e.g. Wallace
and Leslie, 2008) and Sititunga (Games 1983).
Even so, there was surprisingly little on Okavango amphibians, rodents or most reptiles.
Most web hits referred to tourism and the larger mammals found in the Okavango Delta.
Many of these species are not wetland species and are associated with the river system
particularly for water and forage during the dry season or simply because the location of the
various protected areas include wetlands or the river.
Southern African literature was available to varying degrees on most of the species, see
below. General worldwide links between particular taxa and riverine wetlands were also
searched for using combined keywords such as floodplain, pool, frog, amphibian, otter,
Varanus etc.
There are increasing numbers of websites attached to organizations and specialist groups
that provide status and research reports on wildlife species or ecosystems and with links to
other groups and literature. Some relevant ones are included in the References.
The current Namibian checklist of wildlife species for frogs, reptiles and mammals (Griffin
and Coetzee 2005) lists 38 frog species, 75 reptile species and 124 mammal species that
are known or expected to occur in the area of the Okavango River in Namibia. Of these, ten
frog species, eight reptile species and 18 mammal species are thought to be dependent on
the Okavango River wetland habitats in Namibia. Over 90% are classed as being of national
conservation concern. (Griffin 2004).
4.2
Wildlife Indicator 1 : Channel Dwellers
Main characteristics of the habitat
The main Okavango River channel is well defined in both Namibian sites. Associated main
channel river habitats include the Namibian seasonal floodplains which are relatively narrow
and discrete and short sections where the channel is braided around small islands. The
main channel habitat is typically from 50-150m wide, gently meandering with clear water, a
sandy substratum. The banks are typically defined by reed or papyrus beds. Sandbars,
rocks, small islands and rapids add structure in some sections.
Species dependent on this habitat.
Nile Crocodile, Crocodilus niloticus Laurenti, 1768. Hippopotamus, Hippopotamus amphibius
Linnaeus, 1758. Spotted-necked Otter, Lutra maculicollis Lichtenstein, 1835.
These semi-aquatic keystone species use the channel as their main daily habitat for
protection from human disturbance, to travel along, for social interaction and for finding or
obtaining access to food. The characteristics of the main channel in any particular reach are
especially important for the occurrence of the representative species during the low flow
season when the channel width and depth decreases. These characteristics determine the
33
EFA Namibia Wildlife
time and use of the habitat by the different species. The Namibian Okavango population of
Hippo was about 351 or 3.9/km² (of surveyed area) in 2007, mainly in protected areas
(Chase 2007), and Crocodile about 35 or 0.48/ km² (Chase 2007) compared with corrected
counts in 2004 of 66 individuals greater than 2m and 38 less than 2m (Brown et al 2005).
The highest densities of both species are found in the protected areas in Namibia.
Life cycle attributes of Indicator 1 representative species.
Hippo mate, are born and suckle in water where they also spend the day largely submerged
in groups. They repeatedly use the same locations, returning after nocturnal foraging trips.
They leave the water at night to graze individually on land.
Crocodile sub-adults and adults use the main channel for moving and finding food, which is
primarily fish with the occasional mammal. Juveniles frequent vegetation and backwaters
and feed mainly on aquatic invertebrates and amphibia with the occasional small mammal.
(Wallace and Leslie 2008). Nests are made on island and main banks, often in clearings in
reed and papyrus beds where about 60 eggs are laid at the end of the dry season (Blomberg
1976). Nest temperatures determine the sex ratio of hatchlings. The water monitor is a
chief crocodile egg predator (Blomberg 1976): 33% of nests in the Okavango were predated
chiefly by monitors during one survey (Leslie 2005). Humans, fishermen and reed-cutters
have deliberately destroyed nests in the panhandle (Leslie 2005) and can be a principal
threat to breeding success (Wallace and Leslie 2008).
Links to flow
Hippos use the main channel as daytime living space where they rest in pods. Lie up sites
are located on shelving banks where there is a range of water depths (in protected areas) or
on sandbars or pools in midstream if the river is wide enough for protection from human
disturbance outside protected areas or inside pools in vegetation such as Papyrus or
reedbeds in some places if these are available. Hippo prefer a water depth of about 1.5m
(Bruton 1978) which is deep enough to submerge by kneeling or have their backs out of the
water by standing (Scotcher 1974). During low water flows the number of available sites is
reduced and pod sizes can increase.
Crocodile can use all water depths and lie on sand bars and banks where there is access to
deep water.
Water depth and distance from suitable grazing sites from the river banks are important
factors that determine hippo occurrence in the Namibian sites. Main river channel use by
hippo and crocodile in the protected areas of the Namibian sites varies markedly from that
where the banks are populated by humans (e.g. Chase 2007). In protected areas hippo are
frequently out of the water during the cooler parts of the day and both species rest on the
banks or in water close to the banks. In populated areas hippo and crocodile are often
absent from the main channel during the day or are restricted to wide river reaches where
they have some protection from human disturbance. Day time refuge sites for both species
in populated reaches are often inside reed or papyrus beds rather than in open water.
The representative species need sufficient low flow water levels to maintain channel depth,
and reed and papyrus beds. They need high flow water flows to maintain sandbanks and
floodplain vegetation. Early high floods can kill the eggs in lower lying crocodile nests.
Vegetated islands, sand bars and rocks in the main river channel provide protection, feeding
and breeding sites for some channel dependant wildlife. In Namibia Okavango River islands
are protected to some extent from human disturbance and their vegetation tends to be in
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EFA Namibia Wildlife
better condition than that on the bank. Water Monitor Varanus niloticus , African Clawless
Otter Aonyx capensis, Spotted-necked Otter Lutra maculicollis Okavango Hinged Terrapin
Pelusios bechuanicus
Crocodile and Terrapins lay eggs in nests in soil towards the end of the dry-season / start of
summer (Branch 1988) (Leslie 2005). Water Monitors dig nests in termite mounds where the
eggs hatch after rain the following year (Branch 1988). Otters nest in hollows under riparian
trees or rocks eg Rowe-Rowe (1992), Perrin (2000). Young reptiles need protection from
predators amongst island and bank aquatic vegetation which is protected from terrestrial
predators. Hatchlings need access to emergent and fringe vegetation around islands, along
channel fringes and in inundated floodplains and pools. Here they have protection and can
find their largely invertebrate and amphibian food (e.g. Leslie 2005; Broardley 1983; Branch
1988.)
Links to flow
1. Nest sites are vulnerable to flooding from early floods.
2. Sandbanks formed during exceptionally high floods can be used during following
years.
3. Lower low flows make islands part of the bank or more accessible to terrestrial
predators, humans and livestock that can eat or destroy eggs, remove vegetation and
trample banks.
4.3
Wildlife Indicator 2: Frogs and River snakes
Description: Amphibians, snakes and small mammals such as Musk shrews inhabit
floodplain pools, backwaters and emergent vegetation.
Main characteristics of Indicator habitat
Still or low current conditions. Emergent aquatic vegetation provides cover and food.
Backwaters , floodplain pools and emergent vegetation and permanent swamp dwellers.
Channel emergent / floating vegetation stands such as papyrus, reed beds and, lily-pad
beds, along water margins and in backwaters and side channels provide protection, feeding
and breeding sites for many riverine wildlife species. (Eg, Branch 1988; Broadley 1983;
Smithers 1983;, Skinner and Smithers 1990).
Species dependent on this indicator.
Frogs, Snakes, Musk Shrews. Swamp musk shrew Crocidura mariquensis shortridgei, Tiny
musk shrew Crocidura fuscomurina woosnami , Giant musk shrew Crocidura occidentalis
zuleika and Lesser Red musk shrew Crocidura hirta deserti .
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EFA Namibia Wildlife
Life cycle attributes of Indicator
Juvenile reptiles hunt for food and find protection in backwaters and floodplain pools. These
habitats are the living space of frogs, aquatic invertebrates, birds, breeding fish and small
mammals that also form the food of juvenile and sub-adult aquatic reptiles. (Eg Leslie 2005,
Branch 1988, Broardley 1983)
Musk shrews need semi aquatic vegetation of dense grasses and reed beds Smithers
(1983). C.hirta also occurs away from wetlands Smithers (1983). They are largely
insectivorous but may be carnivorous, for instance feeding on frogs, and are active at
intervals throughout the day and night. They breed all year apart from the winter months.
They nest in thick grass or flood deposited debris Smithers (1983).
Links to flow
Occasional very high flows scour out floodplain depressions and form new backwaters.
Seasonal floods fill floodplain pools and maintain floodplain groundwater levels.
Seasonal floods provide fish, aquatic plants and aquatic invertebrates.
Channel flows maintain backwater water levels during dry season. Water levels vary through
the structure of emergent vegetation with the seasonal flood cycle. Floating vegetation such
as papyrus and water lilies move or grow with changing water levels At low water there is
less of this indicator habitat available whereas during floods vegetation on the floodplains are
also available.
Amphibian and aquatic invertebrate lifecycles are dependant on a minimum inundation
period of 1-2 months (Carruthers 2001).
Annual floods are needed to maintain vegetation and habitat for invertebrates and
amphibians. Fast rises in water level or unseasonal high flows may flood Musk shrew nest
sites.
4.4
Wildlife Indicator 3: Middle Floodplain grazers
Species dependent on this indicator. Secondary seasonally flooded floodplain species
such as , Elephant Loxodonta africana,, Buffalo Syncerus caffer, Tsessebe Damaliscus
lunatus and Warthog.
Description of habitat: Flooded vegetation during seasonal floods, new growth of aquatic
grasses, as the flood recedes the resources become available to terrestrial grazers as well
as small mammals Middle (secondary) floodplain is inundated for a shorter time over the
flood peak, than lower (primary) floodplain and is available for non aquatic floodplain species
when the seasonal floodplain is inundated. Vegetation here is denser and taller and is also
used by species such as reedbuck and small mammals.
Information on Namibian Floodplain grazing Species :
Floodplain Grazers occurring in the Namibian UOA include Hippopotamus Hippopotamus
amphibius , Red Lechwe Kobus leche, Southern Waterbuck Kobus ellipsiprymnus, Common
reedbuck Redunca arundinum and Buffalo Syncerus caffer. A Namibian hypermedia
document, http://www.nnf.org.na/RARESPECIES/InfoSys/Index.htm is available on the
Namibia Nature Conservation website, as part of the Transboundary Mammal Project of the
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EFA Namibia Wildlife
Ministry of Environment and Tourism. This hypermedia network of information gives details
of the numbers, distribution, habitats, behaviour, limiting factors and population dynamics of
some of the larger wetland associated mammals of the Caprivi and Okavango in Namibia,
together with management plans. Presently the species covered include Buffalo Syncerus
caffer, Elephant Loxodonta africana, Hippo, Hippopotamus amphibious, Roan Hippotragus
equinus, Sable Hippotragus niger , Tsessebe Damaliscus lunatus, Reedbuck Redunca
arundium, Waterbuck Kobus ellipsiprymnus, Red lechwe Kobus leche,and Puku Kobus
vardoni.
The Namibian Okavango Buffalo population occurs in the western core areas of the
Bwabwata National Park and is effectively isolated from other buffalo by lack of water in the
central part of the park and from Botswana by the veterinary fence. Buffalo are regulated by
their food supply a decline in quality and quantity of available food during the dry season
limits the population (Sinclair 1975). Perennial Panicum grass species preferred by buffalo
(P. coloratum, P. maximum, P. repens) are present in the northern areas of Namibia and
P.coloratum was reported in Curtis's vegetation report as part of this study.
During the dry season the buffalo occurring in UAO 5 frequent the floodplains of the
Okavango in large herds that disperse during the wet season.
Links to flow: For all floodplain grazers, regular floods are needed to maintain the primary
and secondary floodplain vegetation. In any one flood cycle the proportion of seasonal to
secondary floodplain may influence the distribution of floodplain grazers and small mammals.
Un-inundated floodplain vegetation is normally available to wildlife during flood periods
except during flood peaks. Middle floodplains are maintained by large floods and seasonal
flood peaks and are inundated for two to six months.
4.5
Wildlife Indicator 4: Outer floodplain grazers
Representative species: Tertiary floodplain channel riparian zone and Delta island grassland
species such as Wildebeest, Zebra, Impala, Duiker, Aardvark, and mice.
Main characteristics of Indicator habitat The riparian zone along floodplain and channel
margins and on larger / higher islands. This vegetation zone is occasionally flooded during
very high floods but is normally dependent on river associated groundwater (Trees) or local
rainfall (grasses). Provides non-aquatic and floodplain wildlife with cover and grazing
especially during flood periods when other floodplain types are inundated. Riparian trees /
forest with species such as Garcinia livingstonei ,Albizia versicolor and Diospyros
mespiliformis.
Links to flow: Ground water linked to river water sustains the riparian zone during the dry
season. The grasslands and lower riparian tree line margin is maintained by periodic high
floods. A longer flood interval will allow encroachment of trees onto the floodplain. In
Namibia the riparian zone forests are more dependant on the extent of human caused
deforestation than any changes in flow regime.
4.6 Wildlife
indicator
5:
Lower floodplain grazers
Primary seasonally flooded floodplain dependant species such as Reedbuck Redunca
arundium, Waterbuck Kobus ellipsiprymnus, Red lechwe Kobus leche and Sitatunga
Tragelaphus spekei
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EFA Namibia Wildlife
Main characteristics of Indicator habitat
.
Other species dependent on this indicator habitat.
and non aquatic species such as the small mammals. This dependency is chiefly over the
flood peak of high floods when the other riverine habitats are inundated. Otters and monitors
lie up in bank thickets and tree roots during the floods season for protection and basking.
Some bats are also dependant on riparian forests but no flow related information could be
found. They are probably dependent on wetland associated invertebrates such as
mosquitoes, mayflies and cyronomids *
Reedbuck are chiefly nocturnal. require tall grass or reedbeds for daytime cover (Smithers
1983). They seem to do well on poor grassland as long as cover and water are available.
They prefer open areas and avoid woodland and bush encroached areas. Clear burning
causes them to vacate habitat. They do not seem to be attracted to fresh sprouting grasses
after fire as much as other grazers (Howard 1987). Poaching and dogs threaten
reintroduced animals (Rowe-Rowe 1991)
Red Lechwe are water-loving antelope that frequent shallow inundated floodplains and will
feed in water up to 0.5m deep. They seldom drink in the cool, dry season.
Martin (2004) compiled a list of plant species eaten by reedbuck, waterbuck, lechwe and
puku based on the feeding studies by Jungius (1971) and Child and von Richter (1969):
4.9 Summary
The literature on the distribution and ecology of the larger wildlife, the floodplain grazers such
as Red Lechwe, Waterbuck and Reedbuck, as well as Hippo, Otters and Crocodile are good
and sufficient for the purposes of this initial water flows assessment. Most species are
Southern African rather than Namibian Okavango River dwellers and there are more data on
the Okavango Delta in Botswana than on the Namibian section of the river. There are new
studies (Hippo) and studies in progress (Crocodile, Otter, Elephant) in the Okavango system.
These should produce new information on the particular ecology of these species in the
Okavango system and especially their relationships with river flows, which may be used for a
future full flows assessment. The literature giving details of habitat requirements of the other
taxa are generally Southern African rather than on the Okavango in particular. For these
taxa water-flow related habitat needs had to be inferred from reported breeding seasons,
food preferences etc.
Major knowledge gaps are information on particular water flow needs of most of the smaller
indicator representative species including Namibian amphibians, small mammals and bats.
Even the taxonomy and biogeography of many Namibian amphibian and some rodent groups
is still deficient.
There are increasing numbers of specialized web sites where information and literature on
wildlife can be found together with links to other aspects such as conservation, human
interactions, community based management, studies and specialist groups. Some of these
are given after the references.
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EFA Namibia Wildlife
DATA COLLECTION AND ANALYSIS
5.1 Methods for data collection and analysis
The representative sites for each of the Namibian units of analysis were visited once in the
dry and twice in the wet season.
The objectives of the field visits were to gain impressions of the UOAs and their habitats so
that flow related indicators could be suggested that would reflect the effects of changes in
water flows on representative wildlife species. Sightings or signs of wildlife were looked for
to confirm the presence of representative species.
Kapako floodplain site was visited three times, in October 2008, January 2009 and in
February 2009. During the second visit the water was much higher than normal for January
and most of the floodplain was inundated.
Visit 1. Walks over the dry floodplain and along the river bank produced some wildlife
occurrence information. (See Appendix A Map, Wildlife 1. Site 3)
Visit 2. Floodplain was flooded; walks in the riparian zone and on small floodplain islands
produced some wildlife occurrence information for the site. (See Appendix A Map, Wildlife 1.
Site 4)
Visit 3. The floodplain was flooded. To see if small mammals still frequented the remaining
small floodplain islands, two small-mammal trap lines were setup on small islands that were
located on the main channel edge of the floodplain. One was about 150m from the dry bank
and the other about one km. Both islands were about 80m long and 30m wide with a line of
River Rhus Searsia quartiniana. The dry areas were covered by terrestrial grass clumps
and sedges merging into flooded hippo grass Vossia cuspidata on the floodplain side, with
some reeds fringing the open water along the side of the main river channel. Sherman live
traps were placed 10m apart along the spine of each island (six and eight) in the evening and
collected the next morning. (See Appendix A Map, Wildlife 1. Sites 1and 2)
Popa rapids site was visited on in October 2008, and January and February 2009
Visit 1. Walks over the rapids, on the islands and along the banks produced some wildlife
occurrence information.
Visit 2. Ditto.
Visit 3. Sherman live traps for small mammals were placed on two of the islands and along
the north river bank. (See Appendix B for site map.) Site 1, north bank trap line, site 2 north
island trap line and site 3 south island trap line.
5.2 Results
Kapako visit 1. The quite varied topography of the floodplain which is composed of a series
of banks interspersed with lower areas and floodplain pools was noted. Because of this the
floodplain vegetation and hence wildlife habitats was also varied. Cattle grazing on the
floodplain had depleted the vegetation cover in some areas, especially around the floodplain
pools and along the river bank where there was also some erosion. Some pools appeared to
have been recently netted by people as the water was turbid and aquatic vegetation was
pulled onto the banks.
Signs of wildlife were:- Crocodile 2, Water monitor 2, Otter sign, Hippo sign. Duiker sign.
unidentified rodent sign, Cattle 30+.
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EFA Namibia Wildlife
Kapako visit 2. All the habitats for the indicators were present except indicator two, Channel
Island, sand and rock bars. Wildlife or wildlife sign was:- Water monitor 2, Spotted necked
Otter 2, Mole rat sign, Hippo sign, Ridged-frogs Ptychadena spp, Duiker sign, unidentified
rodent sign, Cattle 30+, Goats, dog.
Kapako visit 3. The trap lines on the small floodplain islands, sightings and sign was:-
Swamp musk shrew Crocidura mariquensis shortridgei trapped, 1(Site 1), Spotted Necked
Otter 1, Hippo sign, Multimamate mouse Mastomys natalensis ovambiensis Trapped 1 (site
1), cattle, goats, dog.
Popa Rapids visit 1. Wildlife sightings or sign were:- Hippo 6, Otter spraints. Frogs *
Popa Rapids visit 2. Wildlife sightings or sign were:- Cane rat sign, Hippo 1, Hippo sign,
Terrapin sign, small spotted genet, Puddle frog Phrynobatrachus natalensis,
Popa Rapids visit 3. The trap lines on the channel islands, sightings and sign was:- Hippo
sign, Otter sign, Swamp Musk Shrew Crocidura mariquensis shortridgei trapped,1 (site 2).
Frog* trapped, 1 (Site 2), Serval, Felis serval midden, Multimamate mouse Mastomys
natalensis ovambiensis Trapped 1 (site 3) Boomslang, Chobe Dwarf Gecko Lygodactylus
capensis and Puddle frog Phrynobatrachus natalensis at Popa camp.
5.3 A summary of present understanding of the predicted responses of all
wildlife indicators to potential changes in the flow regime
The following tables give a broad idea of how changes to flow patterns may impact the
habitats and hence the wildlife indicators linked to those habitats.
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EFA Namibia Wildlife
5.3.1 Indicator 1. Main channel dwellers. (Hippo, Crocodile, Otters)
Table 5.1 Predicted response to possible changes in the flow regime of main channel dwellers in the Okavango River ecosystem
Question
Season
Possible flow change
Predicted response of indicator
Confidence
number
Onset is earlier or later than
Earlier = nil
1
Medium
natural
Later = Channel deeper for longer so islands are protected, good for reptile pops.
Higher = deeper channel, more living space for both hippo and crocodile, perhaps fewer
Dry Season
Water levels are higher or
2
dry sand breeding sites for crocodile.
Medium
lower than natural
Lower = shallower channel ,fewer safe locations,
3
Extends longer than natural
Lower channel depth at season end and so fewer safe locations
Duration is longer or shorter
Longer =more time for nesting of crocodile
4
than natural - i.e. hydrograph
Shorter= less time for nesting of crocodile
Transition 1
is steeper or shallower
Flows are more or less
5
variable than natural
Onset is earlier or later than
Earlier = Breeding of some crocodile maybe disrupted by flooding of nests
6
natural synchronisation with
Later = Breeding of some crocodile maybe disrupted. Juveniles need access to floodplains
Flood
rain may be changed
and backwaters.
season
Natural proportion of different
Higher high-flows = good for sandbank development, good for pool scouring.
7
types of flood year changed
Lower high-flows = less flow for channel maintenance as above
Earlier = floodplains dry out sooner=Juvenile crocodile have to return to main channels
Onset is earlier or later than
8
where there is less food and protection.
natural
Later = more habitat for juvenile Crocodile.
Transition 2
Duration is longer or shorter
9
than natural i.e. hydrograph
is steeper or shallower
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EFA Namibia Wildlife
5.3.2 Indicator 2 Frogs and snakes (Frogs snakes and musk shrews))
Table 5.2 Predicted response to possible changes in the flow regime of Channel island, sand-bar and rock-bar dwellers in the Okavango River ecosystem.
Question
Season
Possible flow change
Predicted response of indicator
Confidence
number
Onset is earlier or later than
Earlier=emergent vegetation dries out sooner, reedbeds dryer sooner =.
1
medium
natural
Later =backwaters deeper for longer = reedbeds watered for longer.
Dry Season
Water levels are higher or
Higher =Better marginal and emergent vegetation = more habitat = increased survival.
2
lower than natural
Lower = reedbeds and marginal vegetation drier = less habitat = decreased survival.
3
Extends longer than natural
Fewer safe locations and resources
Duration is longer or shorter
4
than natural - i.e. hydrograph
Transition 1
is steeper or shallower
Flows are more or less
5
variable than natural
Onset is earlier or later than
Earlier = marginal vegetation and reedbeds flooded earlier. Less habitat available. May
6
natural synchronisation with
flood nests before hatching
Flood
rain may be changed
Later = Habitat available for longer, but hatchlings need inundated floodplain resources.
season
Natural proportion of different
Populations may increase if this habitat is available for longer and reduce if it is inundated
7
types of flood year changed
or dries out sooner than normal
Onset is earlier or later than
8
natural
Transition 2
Duration is longer or shorter
9
than natural i.e. hydrograph
is steeper or shallower
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EFA Namibia Wildlife
5.3.3 Indicator Middle Floodplain grazers.
Table 5.3 Predicted response to possible changes in the flow regime of middle floodpain grazers
in the Okavango River ecosystem.
Question
Season
Possible flow change
Predicted response of indicator
Confidence
number
Onset is earlier or later than
Earlier= pools may dry out sooner =reduced breeding time for amphibians
1
Medium
natural
Later =Pools and backwaters available for longer =increased breeding time for amphibians
Dry Season
Water levels are higher or
Higher =, more pools, less competition for resources= reduced mortality Juvenile reptiles.
2
lower than natural
Lower = fewer pools, more competition for resources= increased mortality.
3
Extends longer than natural
fewer pools, backwaters reduce or dry up= Fewer resources available for adults and young.
Duration is longer or shorter
Longer =floodplains flood later = pool habitat available later and for shorter time.
4
than natural - i.e. hydrograph
Shorter= Floodplains flood earlier=pool habitats available sooner and for longer.
Transition 1
is steeper or shallower
Flows are more or less
5
variable than natural
Onset is earlier or later than
Earlier = Earlier access to floodplain pools and backwaters =good for juveniles.
6
natural synchronisation with
Later = competition for resources greater if onset is delayed. =Food for Juvenile reptiles
Flood
rain may be changed
reduced.
season
Natural proportion of different
Higher high-flows = good for pool scouring=Deeper pools next dry season
7
types of flood year changed
Lower high-flows = less flow for channel maintenance as above
Earlier= pools may dry out sooner =reduced breeding time for amphibians , habitat for
Onset is earlier or later than
8
juveniles.
natural
Later =Pools and backwaters available for longer =increased breeding time for amphibians
Transition 2
Duration is longer or shorter
9
than natural i.e. hydrograph
is steeper or shallower
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EFA Namibia Wildlife
5.3.4 Indicator 4. Species Using outer floodplains.
Table 5.4 Predicted response to possible changes in the flow regime of species dependent on outer floodplains in the Okavango River ecosystem.
Question
Season
Possible flow change
Predicted response of indicator
Confidence
number
Onset is earlier or later than
Earlier= River linked groundwater may reduce vegetation water stress before next flood.
1
medium
natural
Later = nil
Dry Season
Water levels are higher or
Higher = nil
2
lower than natural
Lower = Ditto groundwater effects
3
Extends longer than natural
River linked groundwater dependant trees may be stressed
Duration is longer or shorter
4
than natural - i.e. hydrograph
Transition 1
is steeper or shallower
Flows are more or less
5
variable than natural
Onset is earlier or later than
Earlier = Non aquatic species move into riparian zone earlier -reduced resources.
6
natural synchronisation with
Later = nil
rain may be changed
Flood
Higher high-flows = habitat may be flooded-fewer resources available. less habitat available
season
Natural proportion of different
if inter-flood interval is reduced too much.
7
types of flood year changed
Lower high-flows = less flooding of riparian zone = more habitat available but may become
depleted if inter-flood interval is extended for too long
Onset is earlier or later than
8
natural
Transition 2
Duration is longer or shorter
9
than natural i.e. hydrograph
is steeper or shallower
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EFA Namibia Wildlife
5.3.5 Indicator 5. Lower Floodplain dependant species.
Table 5.5 Predicted response to possible changes in the flow regime of Lower Floodplain dependant species in the Okavango River ecosystem.
Question
Season
Possible flow change
Predicted response of indicator
Confidence
number
Onset is earlier or later than
Earlier= Floodplains will be drier reduced availability of resources e.g. grazing, pools
1
medium
natural
Later =Floodplains will provide good resources for longer
Dry Season
Water levels are higher or
Higher = same as later
2
lower than natural
Lower =same as earlier, Floodplain pools may dry out.
3
Extends longer than natural
Resources may become depleted for floodplain grazers
Duration is longer or shorter
Longer = slower flooding = aquatic vegetation has time to grow and be available to grazers
4
than natural - i.e. hydrograph
Shorter = Faster flooding = water deeper which excludes some floodplain grazers from new
Transition 1
is steeper or shallower
vegetation.
Flows are more or less
5
variable than natural
Onset is earlier or later than
Earlier = inundated floodplain resources available sooner = earlier breeding for frogs and
6
natural synchronisation with
better survival of juvenile reptiles.
Flood
rain may be changed
Later =
season
Natural proportion of different
Higher high-flows = good for sandbank development, good for pool scouring
7
types of flood year changed
Lower high-flows = less flow for channel maintenance as above
Onset is earlier or later than
8
natural
Transition 2
Duration is longer or shorter
9
than natural i.e. hydrograph
is steeper or shallower
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EFA Namibia Wildlife
5.4 Conclusions
Linking the ecological needs of particular species to different water flows in the Okavango River in
Namibia was an interesting exercise that highlighted the following aspects:-
The lack of basic information on all but the larger species, especially the Namibian
populations.
The changing water flows in the river and their extent and periodicity affect a whole chain of
morphological and chemical factors that define the vegetation and hence the riverine
habitats available to wildlife, These interactions were known but never thought about in
detail.
The distributions of the larger wildlife in the Namibian sites has much more to do with a
particular reach's protected status than the availability of flow linked indicator habitat
(presumably because of direct human pressures).
The above means that along the Okavango in Namibia, the larger wetland associated species
are threatened with local extinction. The small existing protected areas are vital for the
biodiversity of the river in Namibia and should be increased at every opportunity through,
for instance, conservancies that include special habitats such as rapids, islands and
floodplains, together with their wildlife species.
Outside protected areas this assessment of what effects changes to the flow regime will have
on the larger wildlife, such as floodplain grazers, is relevant to future potential, e.g. for
reintroducing species, rather than the present distributions of these species.
There are several ongoing and new research projects on some of the larger representative
indicator species. These studies will provide new information on relationships with and
dependence on, particular flow stages of the Okavango River that will be available for the
proposed comprehensive flows assessment.
More work will need to be done on how details of the Okavango River hydrogragh impact the
ecology and lifecycle of the smaller wetland associated species in Namibia.
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EFA Namibia Wildlife
6. Flow-response relationships for use in the Okavango EF-DSS
Response curves for the wildlife indicators were constructed together with the wildlife experts from
Angola and Botswana during a workshop in Windhoek in April 2009. The response curves were
fed into the Okavango Environmental Flow Assessment Decision Support System for use during
the Scenario Workshop in CapeTown in July 2009 but will be provided on a CD linked to the final
report.
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EFA Namibia Wildlife
7. References (*) and limited Bibliography.
General
Special wetlands biodiversity issue of the AQUATIC SCIENCES JOURNAL, featuring the
Okavango: Aquatic Sciences Vol 68, No 3, 239-414.
*Bethune .S, 2003. Impacts on aquatic ecosystems in: Popa falls (Divundu) pre-feasibility study.
Preliminary environmental assessment. NamPower.
*Bethune, S. 1990. Kavango River wetlands. Madoqua 17 2 : 77 112
*Bethune, S. 1992 Unpublished. An updated review of the limnological baseline survey of the
Okavango River in Namibia 1984 1992. Internal report RR/92/3 of the Research Division ,
Department of Water Affairs, Namibia.
*Branch, B. 1988. Field Guide to the Snakes and Other Reptiles of Southern Africa. Struik
Publishers CapeTown.
*Broadley, D.G. 1983. FizSimons Snakes of Southern Africa. Delta Books
Bonyongo, M.C. and Harris, S. 2007. Grazers species -packing in the Okavango Delta, Botswana.
African Journal of Ecology, (4), 527534.
*Channing, A. and M. Griffin. 1993 An annotated checklist of the frogs of Namibia. Madoqua
18:101-116.,
*Carruthers.V. 2001 Frogs and Frogging in Southern Africa. Struik Publishers. CapeTown.
*Curtis, B.A., Roberts, K.S., Griffin, M., Bethune, S., Hay, C.J., and H. Kolberg. 1998. Species
richness and conservation of Namibian freshwater macro-invertebrates, fish and amphibians.
Biodiversity and Conservation 7 4 : 447 466.
el Obied, S. and J. Mendelsohn. 2000. A preliminary profile of the Kavango Region in Namibia.
Every River has its People project. Sida, DRFN.
*Games, I. 1983. Observations of sitatunga (Tragelaphus spekei selousi) in the Okavango Delta
of Botswana. Biological Conservation 27:15770.
*Griffin, M. 2003. Annotated checklist and provisional national conservation status of Namibian
reptiles. Namibia. Wissenschaftliche Gesellschaft. Windhoek, Namibia.
*Griffin, M. and C.G. Coetzee. 2005 Annotated checklist and provisional national conservation
status of Namibian mammals. Technical report 4. Directorate Scientific services Ministry of
Environment and Tourism. Windhoek.
*Griffin, M. 2003. Impacts on mammals, reptiles and amphibians: Popa falls (Divundu) pre-
feasibility study. Preliminary environmental assessment. NamPower.
Griffin, M. 1989. The species diversity, distribution and conservation of Namibian mammals.
Biodiversity and Conservation, 7 (4): 484-494.
Griffin, M. 2005. Diagnostic key to the identification of Namibian chiroptera. Technical report of
scientific services Ministry of Environment and Tourism.
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EFA Namibia Wildlife
*Griffin, M. & Grobler, H.J.W. (1991). Wetland-associated mammals of Namibia - a national
review. Madoqua, Vol 17, Issue 2. p.233-237. ISSN: 1010-2299.
Høberg, P., Lindholm, M., Ramberg, L. & Hessen, D. O. 2002. Aquatic Food Web Dynamics on a
Floodplain in the Okavango Delta, Botswana. Hydrobiologia, 470, 23-30.
Lindholm, M., Hessen, D.O., Mosepele, K. and Wolski, P., 2007. Food webs and energy fluxes on
a seasonal floodplain: The influence of flood size. Wetlands, 27(4):
*Murray-Hudson,M., Wolski,P. and Ringrose,S. 2006. Scenarios of the impact of local and
upstream changes in climate and water use on hydro-ecology in the Okavango Delta, Botswana.
Journal of Hydrology, 331, 73-84.
Ramberg,L., Hancock,P., Lindholm,M., Meyer,T., Ringrose,S., Sliva,J., Van As,J. and
Vanderpost,C. 2006. Species diversity of the Okavango Delta, Botswana. Aquatic Sciences, 68,
3, 310-337.
Ramberg, L., Wolski, P., Krah, M., 2006. Water balance and infiltration in a seasonal floodplain in
the Okavango Delta, Botswana. Wetlands, 26, 3, 677-690.
*Rodwell T.C.,Tagg.J,and Grobler.M. 1995. Wildlife resources of the Caprivi, Namibia: The
results of an aerial census in 1994 and comparisons with past surveys. Research Discussion
Paper 9. Ministry of Environment and Tourism.
*Taylor, P.J. 2000. Bats of Southern Africa. Guide to Biology, Identification and Conservation.
University of Natal Press Pietermaritzburg.
dos Sontos Leile, F.A. 1997. Specialist report on: Fauna and flora of the Okavango River Basin
(Angolan Sector) in: Okacom Diagnostic Assessment. GEF Project Brief compiled by S Crerar for
Okacom
Martin, R,B. 2008. Background Information and species Management Guidelines for Namibia's
rare and Valuable Wildlife. Transboundary Mammal Project of Ministry of Environment and
Tourism, Namibia facilitated by The Namibia Nature Foundation and the World Wildlife Fund LIFE
Programme.
*Martin, R.B. (2004). The Wetland Grazers: Species Report for Reedbuck, Waterbuck, Red
Lechwe and Puku. Study conducted for The Transboundary Mammal Project of the Ministry of
Environment and Tourism, Namibia facilitated by The Namibia Nature Foundation and the World
Wildlife Fund LIFE Programme
Mendelsohn, John & Carole Roberts (1997). An Environmental Profile and Atlas of Caprivi.
Directorate of Environmental Affairs, Ministry of Environment and Tourism, Republic of Namibia.
45pp
*Mendelsohn, John & Selma el Obeid (2004). Okavango River The flow of a lifeline. Publ.
RAISON (Research and Information Services of Namibia) & Struik Publishers, Capetown. 176pp
*Simmons, R.E., C.J. Brown and M Griffin Eds (1991). The Status and Conservation of Wetlands
in Namibia, Special Wetlands Edition . Proceedings of a Wetlands workshop held on 22
November 1988 in Windhoek Namibia. Madoqua 17 2.
*Skinner,J.D. and R.H.N. Smithers. (1990). The Mammals of the Southern African Subregion.
University of Pretoria, Pretoria, RSA. +771pp.
*Smithers, R H.N. (1983). The Mammals of the Southern African Subregion. University of Pretoria,
Pretoria, RSA. 736pp
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*Van Aarde R.J. & S.M. Ferreira. 1997. Mammals of the Okavango River system in Namibia and
the Okavango Delta in Botswana. In:- Feasibility study on the Okavango River to Grootfontein link
of the Eastern National Water Carrier. Report for Department of Water Affairs.
Wager, V.A. 1986. Frogs of South Africa: Their fascinating life stories. Johannesburg. Delta
Books.
*Wallace K.M. and A. J. Leslie 2008. Diet of the Nile Crocodile Crocodylus niloticus in the
Okavango Delta, Botswana. Journal of Herpetology 42(2):361-368.
OTTERS
Perrin, M.R. & d'Inzillo Carranza, I. (1999) Capture, Immobilization and Measurements of the
Spotted-Necked Otter in the Natal Drakensberg, South Africa. S. Afr. J. Wildl. Res. 29: 52 53
Perrin, M.R. & d'Inzillo Carranza, I. (2000a) Activity Patterns of Spotted-Necked Otters in the Natal
Drakensberg, South Africa. S. Afr. J. Wildl. Res. 30: 1 7
*Perrin, M.R. & d'Inzillo Carranza, I. (2000b) Habitat Use by Spotted-Necked Otters in the
KwaZulu-Natal Drakensberg, South Africa. S. Afr. J. Wildl. Res. 30: 8 - 14
Perrin, M.R. & d'Inzillo Carranza, I. & Linn, I. J. (2000c) Use of Space by the Spotted-Necked
Otter in the KwaZulu-Natal Drakenberg, South Africa. S. Afr. J. Wildl. Res. 30: 15 21
Perrin, M. R. & Carugati, C. (2000d). Food habits of coexisting Cape clawless otter and spotted-
necked otter in the KwaZulu-Natal Drakensberg, South Africa. South African J. of Wildl. Research
30(2):85-92.
Perrin, M. R. & Carugati, C.. (2000e). Habitat use by the Cape clawless otter and spotted-necked
otter in the KwaZulu-Natal Drakensberg, South Africa. South African J. of Wildl. Research
30(3):103-113.
Rowe-Rowe, D. T. (1977a). Food ecology of otters in Natal, South Africa. Oikos 28:210-219.
Rowe-Rowe, D. T. (1977b). Prey capture and feeding behaviour of South African otters. The
Lammergeyer 23:13-21.
*Rowe-Rowe, D. T. (1992). Survey of South African otters in a fresh-water habitat, using sign.
South African J. of Wildl. Research 22:49-55.
Rowe-Rowe, D. T. & Somers, M. J. (1998). Diet, foraging behaviour and coexistence of African
otters and the water mongoose. Symposia of the Zool. Soc. of London 71:216-227.
Van Niekerk, C. H., Somers, M. J. & Nel, J. A. J. (1998). Fresh-water availability and distribution of
Cape Clawless otter spraints and resting places along the south-west coast of South Africa. South
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web-site of the Hippo Specialist Subgroup of the IUCN/SSC Pigs, Peccaries and Hippo Specialist
Group. http://moray.ml.duke.edu/projects/hippos.
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McCarthy, T.S., Ellery, W.N., and Bloem, A. (1998 Mar) Some observations on the
geomorphological impact of hippopotamus (Hippopotamus amphibius l) in the Okavango Delta,
Botswana. African Journal of Ecology, 36(1); pp. 44-56.
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food shortage. Mammalia 56 (3):345-349.
O'Connor, T.G. & Campbell, B.M. (1986). Hippopotamus habitat relationships on the Lundi River,
Ghonarezhou National Park, Zimbabwe. African Journal of Ecology 24:7-26.
Scotcher, J.S.B. (1978). Hippopotamus numbers and movements in Ndumu Game Reserve.
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Game Reserve, Natal, as determined by faecal analysis. South African Journal of Wildlife
Research 8(1): 1-11.
Van Hoven, W. (1974) Ciliate protozoa and aspects of the nutrition of the hippopotamus in the
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Van Hoven, W. (1977). Stomach fermentation rate in the hippopotamus. South African Journal of
Science 73: 216.
Van Hoven, W. (1978). Digestion physiology in the stomach complex and hindgut of the
hippopotamus (Hippopotamus amphibius). South African Journal of Wildlife Research 8 (2): 59-
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Viljoen, P. C., & H. C. Biggs. (1998). Population trends of hippopotami in the rivers of Kruger
National Park, South Africa. Pages 251-279 in Behavior and Ecology of Riparian Mammals, N.
Dunstone and M. L. Gorman, editors. Symposia of the Zoological Society of London, Cambridge
Press, London, UK.
Viljoen, P.C. (1980). Distribution and numbers of the hippopotamus in the Olifants and Blyde
Rivers. South African Journal of Wildlife Research 10: 129-132.
Wright, P.G. (1987). Thermoregulation in the hippopotamus on land. South African Journal of
Zoology 22(3):237-242.
The IUCN/SSC Hippo Specialist Sub-Group website. Promotes scientifically-based action for the
conservation of common and pygmy hippos. Becca Lewison
Crocodile
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EFA Namibia Wildlife
Aust,P. Research proposal: Conservation of Nile Crocodiles in north-eastern Namibia: ecology,
socioeconomics and sustainable utilization. NNF
Crocodile Conservation Website: http://academic.sun.ac.za/consecol/okavango
*Brown, C.J., Stander, P., Meyer-Rust, R., Mayes, S. 2005. Results of a Crocodile Crocodylus
niloticus survey in the river systems of north-east Namibia during August 2004. CoP13 Inf. 26
CITES Proceedings of the Thirteenth meeting of the Conference of the Parties in Bangkok,
Thailand. [pdf 1,621kb]
Gans, C. Pooley, A.C. 1976. Research on Crocodiles. Ecology 57 (5): 839-840 1976
Hutton, J. M. 1992. The CITES Nile Crocodile project. A publication of the Secretariat of the
Convention on International Trade in Endangered Species of Wild Fauna and Flora, Lausanna,
Switzerland.
Ligomeka, B. 2000. Malawi Plans Crocodile Management Programme. Environment News
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*Leslie A.J. 2005. Crocodiles of the Okavango. Earthwatch Institute Field Report.
Revol, B.1995. Crocodile Farming and Conservation, the example of Zimbabwe. Biodiversity
Conservation 4 (3): 299-305 APR 1995
Thorbjarnarson, J.1999. Crocodile Tears and Skins: International Trade, Economic Constraints,
and Limits to the Sustainable Use of Crocodilians. Conservation Biology, Pages 465-470 Volume
13 No. 3
*Wallace K.M. and A. J. Leslie1 2008. Diet of the Nile Crocodile (Crocodylus niloticus) in the
Okavango Delta, Botswana Journal of Herpetology 42(2):361-368.
Useful Websites
Namibia Nature Foundation: Home
Harry Oppenheimer OKAVANGO RESEARCH CENTRE: http://www.orc.ub.bw/
http://www.biodiversity.org.na/dbase/database.php
Aquatic biodiversity (Darwin project)
Okavango Research Group www.wits.ac.za
Ramsar Convention Secretariat (www.ramsar.org).
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EFA Namibia Wildlife
Appendix A Site Maps
APPENDIX 1: Figure 1: Kapako study site in the dry season showing position of small mammal
traplines sites 1 and 2 and and bases for general examinations of the floodplains for
wildlife sites 3 (dry season) and 4 (wet season).
53
EFA Namibia Wildlife
.
APPENDIX 2: Figure 2: Wildlife study sites at Popa Falls in the dry season showing the position of
small mammal traplines on both banks and on the vegetated island.
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EFA Namibia Wildlife
Appendix B. Species list.
Striped swamp snake
Limnophis
bicolor
Olive marsh snake
Natriciteres
Frogs
olivacea (Peters, 1854)
Flat-backed
Toad Bufo maculatus
Hollowell,1854
Southern African Python
Python
Sharp-nosed (long) reed frog
Hyperolius
natalensis (A. Smith, 1840)
nasutus Gunther,1864
Snoring Puddle frog
Phrynobatrachus
Terrapins
natalensis (A. Smith, 1849)
Okavango Hinged Terrapin
Pelusios
Guttural toad
Bufo gutturalis
bechuanicus Fitzsimons 1932
Power, 1927
Helmeted terrapin
Pelomedusa
Kavango dwarf toad
Bufo kavangensis
subrufa (Lacépède, 1789).
Poynton & Broadley, 1988
.
Zambian swamp terrapin
Pelusios
Painted reed frog
Hyperolius
rhodesianus Hewitt,1927
marmoratus angolensis Rapp, 1842.
Ridged (grass) frogs
Ptychadena
Mammals
ssp.
Rodents
Reptiles
Giant Vlei rat
Otymys
Nile
Crocodile
Crocodilus
maximus Roberts 1924
niloticus Laurenti, 1768
Greater
Canerat
Thryonomys
Water
Monitor
Varanus
swinderianus (Temminck, 1827)
niloticus (Linnaeus, 1766)
Vlei
multimammate
mouse
Mastomys
Chobe Dwarf Gecko
Lygodactylus
shortridgei (St.Leger,1933)
chobiensis FitzSimons, 1932
Natal multimamate mouse Mastomys natalensis
ovambiensis Roberts 1926
Fat
mouse
Steatomys
Snakes
pratensis Peters, 1846
Green water snake
Philothamnus
Damara
Mole
Rat
Cryptomys
hoplogaster (Günther, 1863)
damarensis (Ogilby, 1838)
Northern green bush snake
Philothamnus
Bushvelt
Gerbil
Tatera
irregularis
leucogaster(Peters, 1852)
Western green snake
Philothamnus
Groove-toothed Mouse
Pellomys fallax
angolensis Bocage,1882
rhodesiae Roberts,1929
Ornate water snake
Philothamnus
Water Rat
Dasymys
ornatus Bocage, 1872
nudipes (Peters 1870)
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EFA Namibia Wildlife
Bush squirrel
Paraxerus
Common
reedbuck
Redunca
cepapi Roberts 1932
arundinum (Boddaert, 1785)
Sitatunga
Tragelaphus
Mustelids
spekei
African Clawless Otter
Aonyx capensis
(Schinz, 1821)
Buffalo
Syncerus caffer
Spotted-necked
Otter
Lutra
maculicollis Lichtenstein, 1835
Other
Mammals
Aardvark
Orycteropus afer
Viverrids
(Pallas, 1766)
Civet
Vivera civetta
volkmanni Lundholm 1955
Rusty-spotted
genet
Genetta maculate
Bats
(Grey,1830)
Ruppell's Bat
Pipistellus
Genet
Genetta genetta
rueppellii
(Linnaeus,1758)
Damara wooly Bat
Kerivoula
Water
Mongoose
Atilax
argentata (Tomes 1961)
paludinosus G.Cuvier,1829
Angola Free_Tailed Bat
Mops condylurus
Shrews
(A.Smith, 1833)
Swamp
musk
shrew
Crocidura mariquensis
Rendall's Serotine Bat
Neoromicia
shortridgei St Leger, 1932
rendalli (Thomas)
Tiny musk shrew
Crocidura fuscomurina
Egyptian tomb Bat
Taphozous
woosnami Dollman 1915
perforatus E.Geoffroy
Giant musk shrew
Crocidura occidentalis
zuleika Dollman 1915
Lesser red musk shrew
Crocidura hirta deserti
Schwann 1906
Floodplain
grazers
Hippopotamus
Hippopotamus
amphibius Linnaeus, 1758
Red
lechwe Kobus leche
(Gray, 1850)
Southern
Waterbuck
Kobus
ellipsiprymnus (Ogilby, 1833)
Common
Duiker
Sylvicapra
grimmia (Linnaeus, 1758)
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EFA Namibia Wildlife
APPENDIX B: RAW DATA
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EFA Namibia Wildlife
The Okavango River Basin Transboundary Diagnostic Analysis Technical Reports
In 1994, the three riparian countries of the Okavango
establish a base of available scientific evidence to
River Basin Angola, Botswana and Namibia agreed
guide future decision making. The study, created from
to plan for collaborative management of the natural
inputs from multi-disciplinary teams in each country,
resources of the Okavango, forming the Permanent
with specialists in hydrology, hydraulics, channel form,
Okavango River Basin Water Commission (OKACOM).
water quality, vegetation, aquatic invertebrates, fish,
In 2003, with funding from the Global Environment
birds, river-dependent terrestrial wildlife, resource
Facility, OKACOM launched the Environmental
economics and socio-cultural issues, was coordinated
Protection and Sustainable Management of the
and managed by a group of specialists from the
Okavango River Basin (EPSMO) Project to coordinate
southern African region in 2008 and 2009.
development and to anticipate and address threats to
the river and the associated communities and
The following specialist technical reports were
environment. Implemented by the United Nations
produced as part of this process and form substantive
Development Program and executed by the United
background content for the Okavango River Basin
Nations Food and Agriculture Organization, the project
Transboundary Diagnostic Analysis
produced the Transboundary Diagnostic Analysis to
Final Study
Reports integrating findings from all country and background reports, and covering the entire
Reports
basin.
Aylward, B.
Economic Valuation of Basin Resources: Final Report to
EPSMO Project of the UN Food & Agriculture Organization as
an Input to the Okavango River Basin Transboundary
Diagnostic Analysis
Barnes, J. et al.
Okavango River Basin Transboundary Diagnostic Analysis:
Socio-Economic Assessment Final Report
King, J.M. and Brown,
Okavango River Basin Environmental Flow Assessment Project
C.A.
Initiation Report (Report No: 01/2009)
King, J.M. and Brown,
Okavango River Basin Environmental Flow Assessment EFA
C.A.
Process Report (Report No: 02/2009)
King, J.M. and Brown,
Okavango River Basin Environmental Flow Assessment
C.A.
Guidelines for Data Collection, Analysis and Scenario Creation
(Report No: 03/2009)
Bethune,
S.
Mazvimavi,
Okavango River Basin Environmental Flow Assessment
D. and Quintino, M.
Delineation Report (Report No: 04/2009)
Beuster, H.
Okavango River Basin Environmental Flow Assessment
Hydrology Report: Data And Models(Report No: 05/2009)
Beuster,
H. Okavango River Basin Environmental Flow Assessment
Scenario Report : Hydrology (Report No: 06/2009)
Jones, M.J.
The Groundwater Hydrology of The Okavango Basin (FAO
Internal Report, April 2010)
King, J.M. and Brown,
Okavango River Basin Environmental Flow Assessment
C.A.
Scenario Report: Ecological and Social Predictions (Volume 1
of 4)(Report No. 07/2009)
King, J.M. and Brown,
Okavango River Basin Environmental Flow Assessment
C.A.
Scenario Report: Ecological and Social Predictions (Volume 2
of 4: Indicator results) (Report No. 07/2009)
King, J.M. and Brown,
Okavango River Basin Environmental Flow Assessment
C.A.
Scenario Report: Ecological and Social Predictions: Climate
Change Scenarios (Volume 3 of 4) (Report No. 07/2009)
King, J., Brown, C.A.,
Okavango River Basin Environmental Flow Assessment
Joubert, A.R. and
Scenario Report: Biophysical Predictions (Volume 4 of 4:
Barnes, J.
Climate Change Indicator Results) (Report No: 07/2009)
King, J., Brown, C.A.
Okavango River Basin Environmental Flow Assessment Project
and Barnes, J.
Final Report (Report No: 08/2009)
Malzbender, D.
Environmental Protection And Sustainable Management Of The
Okavango River Basin (EPSMO): Governance Review
Vanderpost, C. and
Database and GIS design for an expanded Okavango Basin
Dhliwayo, M.
Information System (OBIS)
Veríssimo, Luis
GIS Database for the Environment Protection and Sustainable
Management of the Okavango River Basin Project
Wolski,
P.
Assessment of hydrological effects of climate change in the
Okavango Basin
Country Reports
Angola
Andrade e Sousa,
Análise Diagnóstica Transfronteiriça da Bacia do Rio
Biophysical Series
Helder André de
Okavango: Módulo do Caudal Ambiental: Relatório do
Especialista: País: Angola: Disciplina: Sedimentologia &
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EFA Namibia Wildlife
Geomorfologia
Gomes, Amândio
Análise Diagnóstica Transfronteiriça da Bacia do Rio
Okavango: Módulo do Caudal Ambiental: Relatório do
Especialista: País: Angola: Disciplina: Vegetação
Gomes,
Amândio
Análise Técnica, Biofísica e Socio-Económica do Lado
Angolano da Bacia Hidrográfica do Rio Cubango: Relatório
Final:Vegetação da Parte Angolana da Bacia Hidrográfica Do
Rio Cubango
Livramento, Filomena
Análise Diagnóstica Transfronteiriça da Bacia do Rio
Okavango: Módulo do Caudal Ambiental: Relatório do
Especialista: País: Angola: Disciplina:Macroinvertebrados
Miguel, Gabriel Luís
Análise Técnica, Biofísica E Sócio-Económica do Lado
Angolano da Bacia Hidrográfica do Rio Cubango:
Subsídio Para o Conhecimento Hidrogeológico
Relatório de Hidrogeologia
Morais, Miguel
Análise Diagnóstica Transfronteiriça da Bacia do Análise Rio
Cubango (Okavango): Módulo da Avaliação do Caudal
Ambiental: Relatório do Especialista País: Angola Disciplina:
Ictiofauna
Morais,
Miguel
Análise Técnica, Biófisica e Sócio-Económica do Lado
Angolano da Bacia Hidrográfica do Rio Cubango: Relatório
Final: Peixes e Pesca Fluvial da Bacia do Okavango em Angola
Pereira, Maria João
Qualidade da Água, no Lado Angolano da Bacia Hidrográfica
do Rio Cubango
Santos,
Carmen
Ivelize
Análise Diagnóstica Transfronteiriça da Bacia do Rio
Van-Dúnem S. N.
Okavango: Módulo do Caudal Ambiental: Relatório de
Especialidade: Angola: Vida Selvagem
Santos, Carmen Ivelize
Análise Diagnóstica Transfronteiriça da Bacia do Rio
Van-Dúnem S.N.
Okavango:Módulo Avaliação do Caudal Ambiental: Relatório de
Especialidade: Angola: Aves
Botswana Bonyongo, M.C.
Okavango River Basin Technical Diagnostic Analysis:
Environmental Flow Module: Specialist Report: Country:
Botswana: Discipline: Wildlife
Hancock, P.
Okavango River Basin Technical Diagnostic Analysis:
Environmental Flow Module : Specialist Report: Country:
Botswana: Discipline: Birds
Mosepele,
K. Okavango River Basin Technical Diagnostic Analysis:
Environmental Flow Module: Specialist Report: Country:
Botswana: Discipline: Fish
Mosepele, B. and
Okavango River Basin Technical Diagnostic Analysis:
Dallas, Helen
Environmental Flow Module: Specialist Report: Country:
Botswana: Discipline: Aquatic Macro Invertebrates
Namibia
Collin Christian &
Okavango River Basin: Transboundary Diagnostic Analysis
Associates CC
Project: Environmental Flow Assessment Module:
Geomorphology
Curtis, B.A.
Okavango River Basin Technical Diagnostic Analysis:
Environmental Flow Module: Specialist Report Country:
Namibia Discipline: Vegetation
Bethune, S.
Environmental Protection and Sustainable Management of the
Okavango River Basin (EPSMO): Transboundary Diagnostic
Analysis: Basin Ecosystems Report
Nakanwe, S.N.
Okavango River Basin Technical Diagnostic Analysis:
Environmental Flow Module: Specialist Report: Country:
Namibia: Discipline: Aquatic Macro Invertebrates
Paxton,
M. Okavango River Basin Transboundary Diagnostic Analysis:
Environmental Flow Module: Specialist
Report:Country:Namibia: Discipline: Birds (Avifauna)
Roberts, K.
Okavango River Basin Technical Diagnostic Analysis:
Environmental Flow Module: Specialist Report: Country:
Namibia: Discipline: Wildlife
Waal,
B.V. Okavango River Basin Technical Diagnostic Analysis:
Environmental Flow Module: Specialist Report: Country:
Namibia:Discipline: Fish Life
Country Reports
Angola
Gomes, Joaquim
Análise Técnica dos Aspectos Relacionados com o Potencial
Socioeconomic
Duarte
de Irrigação no Lado Angolano da Bacia Hidrográfica do Rio
Series
Cubango: Relatório Final
Mendelsohn,
.J.
Land use in Kavango: Past, Present and Future
Pereira, Maria João
Análise Diagnóstica Transfronteiriça da Bacia do Rio
Okavango: Módulo do Caudal Ambiental: Relatório do
Especialista: País: Angola: Disciplina: Qualidade da Água
Saraiva, Rute et al.
Diagnóstico Transfronteiriço Bacia do Okavango: Análise
Socioeconómica Angola
Botswana Chimbari, M. and
Okavango River Basin Trans-Boundary Diagnostic Assessment
Magole, Lapologang
(TDA): Botswana Component: Partial Report: Key Public Health
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EFA Namibia Wildlife
Issues in the Okavango Basin, Botswana
Magole,
Lapologang
Transboundary Diagnostic Analysis of the Botswana Portion of
the Okavango River Basin: Land Use Planning
Magole, Lapologang
Transboundary Diagnostic Analysis (TDA) of the Botswana p
Portion of the Okavango River Basin: Stakeholder Involvement
in the ODMP and its Relevance to the TDA Process
Masamba,
W.R.
Transboundary Diagnostic Analysis of the Botswana Portion of
the Okavango River Basin: Output 4: Water Supply and
Sanitation
Masamba,W.R.
Transboundary Diagnostic Analysis of the Botswana Portion of
the Okavango River Basin: Irrigation Development
Mbaiwa.J.E. Transboundary Diagnostic Analysis of the Okavango River
Basin: the Status of Tourism Development in the Okavango
Delta: Botswana
Mbaiwa.J.E. &
Assessing the Impact of Climate Change on Tourism Activities
Mmopelwa, G.
and their Economic Benefits in the Okavango Delta
Mmopelwa,
G.
Okavango River Basin Trans-boundary Diagnostic Assessment:
Botswana Component: Output 5: Socio-Economic Profile
Ngwenya, B.N.
Final Report: A Socio-Economic Profile of River Resources and
HIV and AIDS in the Okavango Basin: Botswana
Vanderpost,
C.
Assessment of Existing Social Services and Projected Growth
in the Context of the Transboundary Diagnostic Analysis of the
Botswana Portion of the Okavango River Basin
Namibia
Barnes, J and
Okavango River Basin Technical Diagnostic Analysis:
Wamunyima, D
Environmental Flow Module: Specialist Report:
Country: Namibia: Discipline: Socio-economics
Collin Christian &
Technical Report on Hydro-electric Power Development in the
Associates CC
Namibian Section of the Okavango River Basin
Liebenberg, J.P.
Technical Report on Irrigation Development in the Namibia
Section of the Okavango River Basin
Ortmann, Cynthia L.
Okavango River Basin Technical Diagnostic Analysis:
Environmental Flow Module : Specialist Report Country:
Namibia: discipline: Water Quality
Nashipili,
Okavango River Basin Technical Diagnostic Analysis: Specialist
Ndinomwaameni
Report: Country: Namibia: Discipline: Water Supply and
Sanitation
Paxton,
C.
Transboundary Diagnostic Analysis: Specialist Report:
Discipline: Water Quality Requirements For Human Health in
the Okavango River Basin: Country: Namibia
.
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EFA Namibia Wildlife
61