Issue 14: Over exploitation

Widespread unsustainable fishing practices have left capture fisheries with a shrinking resource base which translates into a shrinking contribution to food security. FAO estimates that 11 of the world's 15 major fishing areas and 69 percent of the world's major fish species are in decline and in need of urgent management. Catches of Atlantic cod, for example, have reduced by 69 percent between 1968 and 1992. West Atlantic bluefin tuna stocks dropped by more than 80 percent between 1970 and 1993.

Overall, the state of exploitation of the main fish stocks (in fisheries for which assessment information is available) has remained more or less unchanged since the early 1990s. Recent reviews tend to confirm that, among the major fish stocks for which information is available, an estimated 44 percent are fully exploited and are therefore producing catches that have reached or are very close to their maximum limit, with no room expected for further expansion. About 16 percent are overfished and likewise leave no room for expansion. Moreover, there is an increasing likelihood that catches might decrease if remedial action is not undertaken to reduce or suppress overfishing.

As valuable fish stocks become overfished and harvests shrink, fishers turn to species of lower value. Mid-Atlantic fishers catching bluefin tuna in the 1960s were targeting swordfish a decade later, and by the mid 1980s they had switched to yellowfin tuna.

The challenge now is to keep fish production on the rise to meet the increasing protein needs of a growing global population, while at the same time allowing overfished populations to recover and preventing other species joining the list of the overfished. It is a major challenge.

Aquaculture is the fastest growing food production sector for the last decade, and there is significant potential for continued expansion and growth of aquaculture and culture-based fisheries. It has been proven that aquaculture and inland fisheries have played and will continue to play an important role in human nutrition and poverty alleviation in many rural areas through integrated aquaculture-agriculture farming systems and integrated utilisation of small and medium-size water bodies. Aquaculture is also facing the challenge of sustainable development. To reduce the environmental impacts of aquaculture development as well as avoid impacts on aquaculture caused by non-aquaculture activities, both a result of poor management, further efforts are needed to improve resources use and appropriate environmental management.

Reference:

Taken from: Food and Agriculture Organization of the United Nations (FAO), Viale delle Terme di Caracalla, 00100 Rome, Italy <Enter>

GIWA definition

Over-exploitation refers to the capture of fish shellfish or marine invertebrates at a level that exceeds the maximum sustainable yield of the stock.

Environmental impacts

1. Changes in biological community structure due to overexploitation/depletion of one or more key species

2. Increasing vulnerability of protected species populations

3. Changes in community structure through restocking and habitat manipulation

4. Ecosystem degradation

Indicators

The following are environmental impact indicators for over exploitation of fisheries.

Select the environmental impact indicators that are relevant from the list below and input data into the appropriate indicator sheets.

Fisheries

Biological