Study on Fish Diversity of Doma Reservoir, Nasarawa State, Nigeria

Study on fish diversity of Doma Reservoir, Nasarawa State, Nigeria was carried out at three ’ sampling stations (Kwararafa, Main Dam and Yelwa). A fleet of gill nets of mesh sizes 38.1mm (1.5”), 57.15mm (2.25”), 76.2mm (3.0”), 101.6mm (4.0”), 127.0mm (5.0”), 152.4mm (6.0”) and 177.8mm (7.0”) were used to sample the shore, surface and bottom : water habitats. The sampling period was 24 months covering two (2) wet and two (2) dry ■ seasons (July 2012 to June 2014). The fish samples caught were identified to the species level and morphometric parameters were recorded following standard methods. fish samples belonging to 6 families with 11 species were identified throughout the study period. The family Cichlidae has the highest number of individuals (93.9%) followed Mormyridae (4.0%). The dry season recorded the highest nuniber of fish (1543) representing ' 56.79% than the wet season (1174) representing 43.21%. Spatially, Yelwa station recordedthe highest number individual (1021) representing 37.58%, followed by Kwararafa (950) -■ representing 34.97) and the least recorded in the Main Dam 746 representing 27.46%. Diversity indices show that Simpson’s index of diversity (1-D) range from 0.403 to 0.479,' Shannon’s index (H) range from 0.858 to 1.0007, while the Shannon equitability or evenness (Eh) range from 0.391 to 0.437 .