Fish community changes associated with a small African reservoir

Fish communities of a small Nigerian reservoir and its upstream were studied from 1984-1985 and 1988-1989. The number of species upstream was considerably reduced from 1984/1985 to 1988/1989. The fish communities of upstream and reservoir were similar in 1988/1989. The comparison of upstream and reservoir showed that benthic invertivores and mud/detritus feeders were adversely affected by habitat alterations. The numbers of species valued as food were low in both upstream and reservoir. Both these habitats supported a large number of species sought by aquarists. The value of fish communities in evaluating biotic integrity of stream ecosystems and the need for the sustainable management of reservoir fisheries resources are discussed.