Seasonal Habitat Use of Endemic Freshwater Fishes in the Eşen Stream (SW Türkiye)

This dataset accompanies the study by Karakuş et al. (2026) investigating seasonal habitat associations and environmental drivers of freshwater fish assemblages in a Mediterranean stream ecosystem of southwestern Türkiye. Field surveys were conducted during three seasons (spring, summer, and winter) across multiple stream reaches. At each sampling point, fish abundance data and a suite of habitat and environmental variables were recorded. Habitat descriptors include water depth, current velocity, substrate composition, aquatic vegetation cover, riparian vegetation cover, light availability, and turbidity. Water quality measurements include temperature, dissolved oxygen, conductivity, total dissolved solids (TDS), salinity, atmospheric pressure, and pH (where available). Fish data comprise abundance records of native and non-native species inhabiting the Esen Stream, including endemic taxa of conservation concern and introduced species. The dataset was generated to evaluate species-specific habitat preferences, seasonal variation in habitat use, and the relative importance of local environmental factors structuring fish assemblages in Mediterranean freshwater ecosystems. The data can be used for studies on freshwater fish ecology, habitat suitability modelling, species distribution analyses, conservation planning, stream ecology, and environmental monitoring. Methods summary Fish and habitat surveys were conducted at standardized sampling points within stream reaches during three seasonal periods using backpack electrofishing. Fish abundance and environmental variables were recorded simultaneously to assess relationships between species occurrence patterns and local habitat conditions. Related publication Karakuş et al. (2026). Seasonal Shifts in Habitat Use of Endemic Freshwater Fishes in the Eşen Stream (SW Türkiye)