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Abstract : |
Fish community structure in relation with environmental variables was studied in the Mأƒئ’أ‚آ© River (Ivory Coast, West Africa). Fifty-four freshwater fish species belonging to 35 genera and 20 families were listed. Eight of these species were reported for the first time in this river, whereas fifteen species reported earlier were not found in the present sampling campaign. Fourteen species are found exclusively in the upstream versus three species for the lower stream. Thirty-seven species are common to both sampling areas. The present findings are opposed to the tendency for species composition to increase from the source to the mouth of the river, which is probably due to a major human activity: the exploitation of a gravel pit. Among fish families sampled, Cyprinidae and Alestidae are more abundant, respectively in the upper and lower courses. Significant correlation between species distribution and environmental variables was found. Aquatic plants, canopy closure, conductivity, dissolved oxygen, mixed deadwoods-leaves-rocks, temperature and width are the main environmental variables influencing fish distribution in the Mأƒئ’أ‚آ© River., |
