Adetola Jenyo-Oni and Olute B. W.
Department of Aquaculture and Fisheries Management
University of Ibadan, Ibadan, Nigeria
Oni River in Ogun waterside Local Government area of Ogun State contributes immensely to the artisanal fishery of the state, fishing being the major means of livelihood of the people living along the river course. This study assessed the fish composition in order to obtain the fish species and harvest composition of the study area. The study was conducted by enumerating and identifying the fish species composition of the river through personal interview and direct assessment of fishermen’s catches, fish length and weight were measured. Fish abundance and biomass were assessed and the length-weight relationships and the length–frequency of fishes determined. Twenty-eight fish species belonging to sixteen families were encountered in the study area, the mormyridae were the most abundant family with 25.0%, followed by Cichlidae with 10.71%. Tilapia zillii (11.82%), and Clarias spp. (8.28%) were the most abundant single species. Those with the least abundance in the study area were Sihiranodon anritus and Schilbe mystus each with 0.17% abundance. The Oni River is a highly productive river and should be managed on a sustainable level.