Régime alimentaire de Thysochromis ansorgii (Cichlidae) dans la forêt des marais Tanoé-Ehy (Côte d’Ivoire)
Diet aspects of Thysochromis ansorgii (Cichlidae) in the Tanoe-Ehy swamp forest (Côte d’Ivoire)
The diet of Thysochromis ansorgii (Boulenger, 1901) was studied in the Tanoe-Ehy swamp forest according to fish size and hydrological season. Fish were caught monthly between March 2012 and February 2013 using gillnets and fyke nets. A total of 149 individuals were collected, with standard length and fresh weight ranging, between 45 mm and 110 mm and 3.3 and 64.3 g, respectively. The mean vacuity index was 26.17%. It was lower during the forest rainy season (Cv = 13.43% and Cv =3 6.58%, respectively for rainy and dry seasons). The food composition varied with fish size. Food composition was studied using occurrence, numerical, weigh percentages and Zander Main Food Items index. With 10 items, food spectra showed that T. ansorgii is an omnivorous fish with detritivory tendency. Fruit and plant detritus were the main food, while insects represented secondary preys. Finally, a significant difference was found between the food composition of the Tanoe Ehy Swamp forest rainy and dry seasons, due probably to the seasonality in the food resource availability.