FISH DIVERSITY AND STRUCTURE IN THE BANCO STREAM (BANCO NATIONAL PARK, IVORY COAST)

The fish fauna in the Banco Stream has been investigated to update the inventory of the fish species in this stream in order to establish a basis for the conservation of these fish communities and their habitat. Seven sites were sampled from November 2008 to March 2009 using gill and hand nets, and environmental conditions were determined. A total of 141 fish have been collected and classified into 14 species, 11 families and 5 orders. The order Perci-formes with 7 species belonging to 5 families was the most diversified, followed by Cyprinodontiformes (3 species) and Siluriformes (2 species). The dominant families were Cichlidae and Aplocheilidae. This study has reported 3 species discovered for the first time in the Banco Stream. The diversity of Shannon-Weaver (1.20-2.70 bits/ind.) and the evenness (0.76-0.99) indices indicated that the habitat was slightly disturbed and the species distribution was regular. A zonation was observed in fish assemblages from the Banco Stream; species belonging to pis-civorous or aquatic invertivorous guilds were predominant downstream and those with an opportunistic omnivorous diet more abundant in upper zones. The distribution of these species was more influenced by some environmental conditions.