Biologie et écologie des poissons d'eau douce africains = Biology and ecology of african freshwater fishes

Abstract

Itroductions of non-endemic fishes into inland waters in Africa are discussed with special reference to their influence on African fisheries. Fish introductions have been made for various reasons : introduction of fastgrowing fishies for fishculture, introduction of predatory fishes to control fish production in ponds, improvement of sport fisheries, control of unwanted organisms e.g. aquatic weeds, snails, mosquitoes, to fill apparently empty ecological niches in natural or artificial water bodies ... Many introduced species have created major problems in African water bodies ... The most serious problem relate to the influence of introduced fishes on native fish stocks. Some endemic species have been drastically reduced or caused to be locally extinct by introduced fishes, either through predation, or competition for food or breeding space ... In general, the "successful" introductions have increased fish yields, but these increases have often been in association with an expansion of fishing effort and the improvment of fishing gea