A preliminary investigation into the fisheries potentials of Doma Lake, Nasarawa State, Nigeria

Abstract

A preliminary investigation into the fisheries potentials of Doma Lake in Nasarawa State, Nigeria was carried out from July to December 2000. Values of physico-chemical parameters (temperature, pH, dissolved oxygen, total alkalinity and free carbon dioxide) did not vary significantly (P > 0.05) between the sampling months. A total of 8 families made up of 11 genera and 16 species of fish were recorded in the lake. The family Cichlidae (67.56%) dominated while the family Hepsetidae was the least (0.45%). Length-weight regression analysis showed that six species of fish (Gnathonemus niger, Channa obscura, Hepsetus odoe, Oreochromis niloticus, Tilapia monodi and Tilapia zilli) exhibited positive allometric growth. Barilius niloticus showed negative allometric growth while Hemichromis bimaculatus showed isometric growth pattern. The mean standard length and weights of most of the species of fish correlated strongly except that of Barilius niloticus, which correlated weakly. The condition factor (K) showed that the smaller sized fishes thrived better in the lake. There were more male than female fish in the lake. Gnathonemus niger exhibited the highest fecundity while the lowest fecundity was observed in Hemichromis fasciatus and Tilapia zilli. The implications of the findings are discussed.


Key Words: Fisheries potentials, Doma Lake, Nigeria


Journal of Aquatic Sciences Vol.19(2) 2004: 59-64