Macrozooplankton communities in Lake Tanganyika indicate food chain differences between the northern part and the main basins

Medusae predominate the macrozooplankton in the northernmost part of Lake T anganyika, while shrimps are more abundant towards the south. In the stomac h contents of centropomidae Lates stappersii (one of the four nile perch sp ecies in the lake), there were more shrimps both in percentage and frequenc y in Mpulungu area in the south, than in Kigoma area in the north where the diet of L. stappersii contained bigger proportion of copepods. The results suggest differences in the food chains of the northern and southern pelagi c ecosystems of Lake Tanganyika. Food chain differences, probably arise bas ically from different patterns of mixing, due to seasonal winds and orienta tion of the lake relative to wind.