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< prev - next > Fisheries Farming fish and aquaculture food_livelihood_and_freshwater_ecology (Printable PDF)
access floodplain by high input agricultural land is having impact on a major food resource: fish. Such projects are
jeopardizing future supplies of fish protein from wild stocks, the main source of animal protein for the poor.
Loss of Fish Production Based on the Loss of Inundated Area to Cropland, calculating
the area actually lost in 1985, and projected to 2005
(Source: MPO Technical Report 17, 1987)
Area of Inundated Flood
Plain Removed
Minimum Loss of Fish (Direct Flood
Plain harvest @ 37 kg/ha/yr)
Maximum Loss of Fish
(Direct Flood Plain Harvest
Plus Contribution of Flood Plain
to River and Beel Fish)
Metric Tonnes
Metric Tonnes
814,441 Hectares
(by June 1985)
2,000,000 Hectares
(by 2005)
Projected Fish Requirement, Demand and Production Potential (Million Tonns)
During base year
Fish Requirement
2000 2010
1649 1998
Fish Demand
2000 2000
1170 1803
2000 2010
1133 2200
2000 2010
2266 3831
The implications of the FAP on aquatic resource production, and on meeting a growing market demand and population
requirement are therefore considerable.
Several authors have highlighted the linkages between the decline of previously common fish species in inland waters, the
transformation of the habitat, and the reduction of water levels in beels and the floodplain. The FAP has produced a plethora
of reports documenting such changes (FAP 1992 to 1994).
Whilst flood control embankments prevent the migration of fish and prawns from rivers to the floodplain and vice versa,
drainage of the beels and flood plains reduces and eventually eliminates fish habitats (Ali, 1997).
Water pollution, much of it from industrial effluents, agrochemicals and domestic organic wastes is also a major threat.
Tanneries, urea, newsprint, paper and pulp plants and jute mills are known to release untreated wastes into rivers and other
water bodies. Pollutants discharged include mercury, lead, chromium, arsenic and iron. Even at relatively low concentrations,
these pollutants can detrimentally effect the aquatic fauna (World Resources Institute, 1990).
Hossain et al (1996) have warned of the dangers of a shrinking gene pool, and loss of genetic diversity. The depletion of
stocks and the loss of species reduces biodiversity, changes the biological and tropic structure of the ecosystem, increases
vulnerability and undermines sustain ability. It also leads to increased fishing pressure being placed on the remaining
species. He identified the following causes for the loss of biodiversity:
reduction in floodplain ecosystems;
expansion in HYV rice production;
indiscriminate use of pesticides; and · pollution and siltation of the river system.
As a result of their cumulative impact, several species of floodplain, riverine and brackish water fish are threatened (Hossain
et aI 1997). Hossain (1997) also lists inter alia the following causes for the decline in SIS: