Seasonal Limnological Dynamics and Surface Zooplankton Responses in a Small Tectonic Lake in Turkiye

Abstract In freshwater ecosystems, zooplankton play a crucial role in pelagic food web and serve as indicators of ecosystem responses to temperature shifts, hydrodynamics, and seasonal meteorological changes. Changes in water temperature, water movements with the environmental factors affect the zooplankton distrubution and occurences. In this study, the epilimnetic zooplankton fauna of Karamurat Lake, Bolu, Türkiye, a small tectonic temperate region lake, was tried to be determined with by rainfall events and wind existence. The samples were taken seasonally and horizontally using a plankton net. A total of 74 zooplanktonic taxa were identified. Of these, 54 species with a new record (Testudinella greeni) belong to the Turkish Rotifera fauna and 20 species from crustaceans, including 16 species from Cladocera and 4 species from Copepoda. Multivariate analyses revealed that electrical conductivity, water temperature, and precipitation were key drivers shaping community structure. The findings suggest that wind induced surface mixing and rainfall events enhance vertical distribution, facilitating the appearance of taxa such as rotifers and small bodied cladocerans in the epilimnion. It has been understood in this study the importance of sampling methods in shallow lake and contributes new faunistic data to the zooplankton diversity of Anatolian lakes.