Patterns and Drivers of Bat Mortality at Wind Farms in Western Türkiye: A Multi-Year Carcass Survey

This study presents a comprehensive assessment of bat mortality associated with certain wind energy facilities in western Turkiye based on multi-year carcass monitoring studies conducted between 2018 and 2024. A total of 169 bat carcasses were recorded, with Pipistrellus pipistrellus accounting for approximately 60% of the observations. Mortality patterns showed distinct seasonal variations, peaking between May and October, with the highest numbers observed in August and September. Statistical analyses, including one-way ANOVA and Tukey HSD post-hoc tests, revealed that P. pipistrellus was exposed to significantly higher mortality rates compared to P. kuhlii and P. nathusii (p < 0.001). Normality tests indicated deviations from normal distribution, leading to the application of the Kruskal-Wallis non-parametric test, which confirmed significant differences between species (p = 0.0022). Mann-Whitney U post-hoc comparisons further determined that P. pipistrellus was significantly more vulnerable than P. kuhlii and P. nathusii . Although the chi-square test did not detect a significant interaction between species and seasons (χ² = 24.29, df = 20, p = 0.230), descriptive trends highlighted seasonal peaks in certain taxa. These findings support international evidence that wind turbines pose significant threats to bats, particularly during critical life stages such as post-breeding dispersal and migration. The study highlights the effectiveness of mitigation measures such as reduction strategies during periods of increased activity and low wind speeds (< 6 m/s) and underscores the need for standardized research protocols, real-time monitoring, and species-specific adaptive management to balance the expansion of renewable energy infrastructure with the conservation of biodiversity in Türkiye.