Ecological niche modeling and genetic structure of brown bear (Ursus arctos) in Türkiye

Türkiye, with its rich biodiversity and unique climatic/topographic characteristics, serves as a land bridge between Asia and Europe. Brown bear (Ursus arctos) is the largest carnivore species in Anatolia. Unfortunately, due to climate change and landscape transformation, brown bear habitats are fragmenting and becoming increasingly isolated, posing a significant conservation concern for the species' future. This thesis comprises the chapters examining the various ecological facets of brown bears across Türkiye. Considering bioclimatic, topographic, and anthropogenic environmental variables, the distribution of brown bears across the country was estimated using an ensemble modeling approach. Potential habitat suitability under different climate change scenarios was also investigated. The results indicate bears are primarily distributed in the Euro-Siberian biogeographic region, followed by Irano-Turanian, and Mediterranean. Climate change is expected to lead to a substantial loss of brown bear habitats. Additionally, it is projected that established protected areas might become insufficient to safeguard the species in the face of future habitat loss, leading to a conservation gap. I modeled the structural connectivity of brown bear habitats across the country, identified priority linkages and core patches, and discussed the potential impact of climate change on the ecological network of brown bears across Türkiye. Ultimately, the Western Black Sea and Eastern Anatolia core patches exhibited a relatively intact structure, while the Mediterranean region was identified as critical in terms of habitat configuration and fragmentation. Climate change is predicted to have significant impacts on brown bear ecological network. Then, I analyzed the spatiotemporal dynamics of human-brown bear conflict across Türkiye. A conflict risk map was generated, and the role of protected areas in mitigating conflict was evaluated. The findings revealed significant variations in conflict frequency by years, seasons, bear seasons, and regions. Conflict risk was found to be particularly high along the Black Sea coast and Eastern Anatolia. The primary cause of human-bear conflicts was identified as the confinement of bears to areas, with limited resources, leading them to seek anthropogenic food alternatives. Additionally, the peripheries of protected areas represented hotspots for human-bear conflict. In the next chapter, I analyzed the population structure and genetic variation of brown bears across Middle East. Results indicated that the Sarıkamış population exhibited a more isolated pattern and lower genetic diversity compared to the Western, Eastern, and Iranian populations. However, high genetic variation was detected across the region. Furthermore, environmental heterogeneity and geographic distance were identified as significant patterns driving the genetic differentiation of populations. Lastly, considering the findings from all preceding chapters, I discuss pro-active wildlife management approaches that promote coexistence. This comprehensive study aims to provide a holistic conservation approach for brown bears by examining their suitable habitats, ecological connectivity, population structure, strategies to mitigate human-bear conflict, and climate adaptation strategies. My results highlight the urgent need for effective conservation measures to safeguard Türkiye's brown bears in the face of climate change, habitat loss, and human-bear conflict.