An analysis of fish distribution in Kainji lake Nigeria

The distribution of fish in the three major habitats (inshore, surface and bottom) in Kainji Lake was studied using gill-nets in graded fleets each consisting of seven nets with mesh sizes ranging from 5 cm to 18 cm. No significant difference was observed in the annual yields of fish in the three habitats. Three of the nine major families, however, gave higher yields in selected habitats. Characidae and Cichlidae were most abundant in the shore and surface and Bagridae in the shore and bottom. Catches of the Cichlidae in the surface were limited to areas where the mean depth was below 7 meters. Analysis of variance showed no significant difference in the overall yields of fish among sampling areas located within the major strata of the lake. Although a general trend was observed in the seasonal yields of fish, with higher yields during low water, the variations were not significant either for the overall annual yields or among sets. The implications of these findings in relation to the mode of life of the major fish species and the stability of the fish population are discussed.