The role of reproductive strategies in recovery and success of selected fish species of Lake Victoria,Tanzania

Abstract

selection of mates, parental care, environmental conditions, clutch size, gonadal maturation and genetic differences in fitness. The present study which started in 1997 investigated factors which favour the reproduction of three fish species, Lates niloticus, Oreochromis niloticus and Schilbe intermedius. The factors investigated included parental care, clutch size, resource mobilization from the environment and gonadal maturation. The results show that Oreochromis niloticus spawns a few eggs about 3,550 in relation to its size (about 57cm in total length). Its success is ensured by being a mouth breeder which is the highest parental care. The other fish species L. niloticus and S. intermedius have no parental care to the laid eggs but spawn large number of eggs in relation to their sizes. Regarding the gonadal maturation the results show that L. niloticus and S. intermedius males have shown to attain sexual maturity much earlier than females. This is a strategy to have many mature males to fertilize the eggs of any female which attains sexual maturity.