Gebawo Tibesso* and Mathewos Hailu
Scientific studies on water quality and productivity can contribute to the assessment of the suitability of water for particular uses such as domestic, irrigation, sanitation, fish production. The primary productivity of different water bodies has been widely investigated to assess the fish production capacity of a water body to formulate fishery management policies. This study aimed at the identifying the retained fish species during initial impoundment of Didesa reservoir and studying the fish establishment feature of the newly built reservoir for estimating their fisheries production potential. Three fish species of two families were recorded in Didesa reservoir. In the present study, Labeobarbus intermedius dominated the catch, Followed by Oreochromis niloticus and Labeo cylindricus. Length-weight relationships were highly significant with high coefficients of determination ranging from 0.97 for Oreochromis niloticus up to 0.990 for Labeobarbus intermedius. The length at first sexual maturity (L50) was 32.9 cm TL while it was 25.4 for Oreochromis niloticus at Dhidhesa reservoir.