Dynamics of the Zooplankton Community of Monastery Lake in Daloa (West-Central, Côte d’Ivoire)

Monastery Lake in Dalea (Côte d'Ivoire) represents an important aquatic ecosystem facing increasing anthropogenic pressures. Despite its ecological and economic importance as a fishing site, no previous study has documented the dynamics of its zooplankton community. The availability of fundamental scientific data is essential for developing appropriate management plans. This study examines the seasonal variation of zooplankton in Monastery Lake in Daloa (West-Central Côte d'Ivoire). Seasonal sampling was conducted from February to September 2024 at three stations. Physicochemical parameters (temperature, pH, dissolved oxygen, conductivity, transparency, depth) were measured in situ. Zooplankton was collected using a 50 µm mesh net, identified using standard taxonomic keys, and then enumerated. The data were used to calculate Shannon diversity and evenness indices, and to analyze correlations between environmental parameters and the zooplankton community. Seventy-one zooplankton taxa were identified, comprising 43 Rotifers, 4 Copepods, 19 Cladocerans and 5 other organisms. Rotifers showed qualitative dominance while Copepods dominated quantitatively across all seasons. Taxonomic richness and zooplankton abundance were higher during the rainy season compared to the dry season. Zooplankton distribution showed negative correlations with temperature, pH and transparency, and positive correlations with depth and dissolved oxygen. This study reveals that zooplankton organisms in Monastery Lake exhibit remarkable diversity and abundance, highlighting the ecological importance of this aquatic ecosystem.