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The feeding habits of Synodontis punctifer were investigated in the basin of the Bandama River. Fish specimens were collected using gill nets in the rainy season (May–July 2009) and in the dry season (November 2008 to March 2009 and August 2009). In this article, the importance of the different prey types was assessed using the corrected occurrence and weight percentage. These values were used to calculate the index of preponderance for each taxonomic category. One hundred and ten specimens of S. punctifer were examined, nine stomachs were found empty (8.18%). A total of 39 different prey species belonging to seven major groups Insects, Crustacea, Rotifera, Molluscs, Other invertebrates, Other organisms and Macrophytes were identified in the stomach contents. The results showed that Macrophytes were the primary food item and Insects the secondary prey item. Other preys were recorded occasionally. At the rainy season, the main foods of S. punctifer were Macrophytes and during the dry season this species ate Insects and Macrophytes. The food composition varied between localities. In the riverine localities, specimen fed on 38 prey types. Twenty-seven prey categories were consumed in the lacustrine. In terms of diet overlap, Schoener coefficient values were above the 0.6 limit (α = 0.99), indicating some high overlap. Resume Les habitudes alimentaires de Synodontis punctifer ont ete etudiees dans le bassin de la Bandama. Des specimens de poissons ont ete collectes au moyen de filets maillants, en saison des pluies (mai – juillet 2009) et en saison seche (novembre 2008 – mars 2009 et aout 2009). Dans cet article, nous avons evalue l'importance des differents types de proies en utilisant l'occurrence corrigee et le pourcentage du poids. Ces valeurs ont servi a calculer l'indice de preponderance pour chaque groupe taxonomique. Nous avons examine 110 specimens de S. punctifer, neuf estomacs ont ete trouves vides (8,18%). Au total, des proies de 39 especes differentes appartenant a sept groupes majeurs, insectes, crustaces, rotiferes, mollusques, autres invertebres, autres organismes et macrophytes, furent identifiees dans les contenus stomacaux. Les resultats montraient que les macrophytes etaient le premier aliment en importance et les insectes le deuxieme. D'autres proies furent enregistrees de facon occasionnelle. A la saison des pluies, la nourriture principale de S. punctifer se composait de macrophytes et, pendant la saison seche, cette espece mangeait plutot des insectes et des macrophytes. La composition de la nourriture variait selon les lieux. Dans des endroits riverains, les specimens se nourrissaient de 38 types de proies. Dans des endroits lacustres, 27 categories de proies furent consommees. En termes de recouvrement de regime alimentaire, les valeurs de l'indice de Schoener se situaient au-dessus de la limite de 0,6 (α = 0.99), ce qui indique un fort recouvrement. |
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