Fish Species Diversity of Nafada, Ashaka and Almakashi Corridors of River Gongola, Gombe State Nigeria

Abstract

Fish species diversity and abundance of Nafada, Ashaka and Almakashi corridors of river Gongola were studied. Fish samples were collected from three (3) landing sites on a monthly basis for the period of eighteen (18) months from artisanal fishers. The landing sites were; Nafada, Ashaka and Almakashi along river Gongola. A total of 25 species from 14 distinct families were identified: Almakashi has 23 species followed by Ashaka having 21 and Nafada with 17 species. Almakashi has the highest abundance of fish species (48.37%), followed by Ashaka (30.33%) and Nafada (21.28%). Fish families were dominated by Mormyridae with four (4) species followed by Alestidae and Bagridae with three (3) species each; Cichlidae, Clariidae, Cyprinidae and Schilbeidae have two (2) species each while Characidae, Citharinidae, Gymnarchidae, Malapteruridae, Mochokidae, Arapaimidae and Polypteridae have one (1) species each. Fish species were dominated by Oreochromis niloticus of the family Cichlidae with abundance of 37.65% followed by Clarias gariepinus of the family Clariidae with 12.54% and the lDiversityeast was Gymnarchus niloticus of the family Gymnarchidae with 0.02%. The ranges of Biodiversity indices of the studied sites were species richness (2.41 - 2.95) and species evenness (0.41 - 0.53). Almakashi has a rich fish species diversity but it is facing challenges of structural collapse that necessitates adoption of comprehensive management strategies for the sustainability of the fisheries resources of river Gongola particularly within the corridors.