Diet of the five main fish species found in urban lakes in Yamoussoukro (central cote D’ivoire)

This study aims to understand the diet of the main fish species, assess trophic interactions and the structure of the trophic network, and detect ecological changes linked to the eutrophication of urban lakes in order to support sustainable management and conservation strategies for fishery resources. It involved sampling fish species every two months, both day and night, in six urban lakes in the city of Yamoussoukro, from July 2021 to May 2022. This made it possible to determine the food composition of the species Oreochromis niloticus (Limnaeus, 1758), Sarotherodon galilaeus (Limnaeus, 1758), Sarotherodon melanotheron (Rüppell, 1852), Coptodon zillii (Gervais, 1848), and Hemichromis fasciatus (Peters, 1857), for which at least 30 full stomachs were analyzed, or 887 full stomachs in total. This analysis identified five categories of food resources: phytoplankton, zooplankton, macroinvertebrates, fish, and others. The species Oreochromis niloticus, Sarotherodon galilaeus, Sarotherodon melanotheron, and Coptodon zillii exploit the same food resources and are planktivorous. Hemichromis fasciatus, on the other hand, is more carnivorous. Knowledge of these diets makes it possible to establish the food web patterns of fish in the various urban lakes of Yamoussoukro and to guide local communities in the management and conservation of these aquatic environments.