Notes on the behaviour of the small mormyrid fishes of Lake Victoria

Seven species of the Monnyridae occur in Lake Victoria and of these only Mormyrus kannume Forsk. and M. macrocephalus Worth. grow to any large size. M. kannume, the commonest species, is of high economic value. The smaller species, Gnathonemus longibarbis Hilg., G. victoriae Worth. Marcusenius grahami Nonn., M. nigricans Blgr., and Petrocephalus catostoma (Gunth.) represent only a minor fraction of the commercial catches except in the rivers where they form a substantial seasonal fishery (Okedi 1966a)