Fish fauna of Kaptai Reservoir: introduced fish species and their effect on reservoir fisheries

Abstract

A preliminary study was carried out to assess the effect of introduction and stocking program of exotic fish species on the diversity and fishery of Kaptai reservoir. Introductions of exotic species for stocking can induce several risks to the environment including the possibility of declining native fish species through competition for resource, predation or genetic interference, and the potential spread of disease. The Kaptai Lake fishery however shown reasonably diversified and rich fishery comprising around forty fish species after the major stocking event occurred during 1980s. The fauna appears to have adapted well to the changes made so far both in impounded waters and in the modified flows downstream. Introductions of several exotic fish species have been made through larval release in the lake to meet the growing demand in local fish consumption. The results of this study showed that out of seven species only Indian major carps have shown some potential to being established as a population in the reservoir and thereby to contribute to the enhancing fishery yield. The rest of the species failed to show any promise to contribute to the lake fishery. The present study indicated that stoking program at Kaptai reservoir is both miscalculated and unproductive. However, the stocking program did not appear to threating the diversity of reservoir Fishery.