COMMUNITY STRUCTURE OF CICHLIDS IN SOME MAJOR LAKES IN NIGERIA

Abstract

The study was conducted to investigate the status of the Cichlidae family in some major lakes of Nigeria namely; Asejire, Oyan, Geriyo, Dadin-Kowa, Kainji, and Jebba. Samples of the cichlid group were collected bi-monthly from the study sites for six months, between July and December 2016. During the study, a total of 6,583 individuals were observed, belonging to seven species, including Coptodon zillii, Pelmatolapia mariae, Sarotherodon galilaeus, Oreochromis niloticus, Chromidotilapia guntheri, Hemichromis fasciatus, and Hemichromis bimaculatus. The highest composition of the six species and abundance, except for H. bimaculatus, was found in Asejire and Oyan lakes, followed by Kainji and Jebba lakes, which had a composition of five species, except for P. mariae and H. bimaculatus. Geriyo and Dadin-Kowa lakes had species compositions of four and three respectively. The study revealed that the species abundance was higher during the wet season, but still reasonable during the dry season, except for H. bimaculatus, which was generally low where it was observed. It was also observed that O. niloticus was dominant in abundance in four study locations compared to S. galilaeus which was dominant in two locations. Shannon-Weiner’s diversity indices indicated that Asejire and Oyan lakes were more diverse and richer in cichlid group, while Geriyo and Dadin-Kowa lakes were less diverse and less rich in cichlid group. Similarly, Pielou’s evenness showed that the cichlid group of Dadin-Kowa Lake is more even in their abundance than from other sites while the Simpson diversity index was higher in Asejire and Oyan compared to other studied sites.