Composition and variation in zooplankton density in fish and rice-fish farming in a lowland at bédiala (Côte d’Ivoire)

Freshwater zooplankton are recognised as an important source of food for fish. The aim of this study was to compare the diversity of zooplankton populations in conventional and rice-fish culture ponds. Sampling campaigns will take place from June 2019 to May 2020 in a lowland in Bédiala. Zooplankton were sampled in the ponds by filtering 100 litres of water using a 64 µm mesh plankton net. Two ponds were used for fish farming and two others were used to simultaneously grow rice and fish. The results obtained show that the specific richness of the zooplankton population of all the ponds is 25 taxa. This population is divided between three permanent zooplankton groups. These are Rotifera (16 taxa), Copepoda (4 taxa) and Cladocera (3 taxa). Taxonomic richness and zooplankton density were significantly higher in rice-fish culture ponds than in fish culture ponds. These are more pronounced during the rainy season in rice-fish culture ponds. Rice-fish culture ponds are thus richer in food resources for fish than fish culture ponds.