Reconciling endangered species conservation with wind farm development: Cinereous vultures (Aegypius monachus) in south-eastern Europe

Harnessing wind energy is seen as an environmentally friendly strategy to combat climate change. However, adverse environmental impacts have come to light for species that are prone to collision with wind turbine blades, such as vultures, leading to a conflict between wind energy industry and conservation. Our study area epitomized such a conflict, containing the only population of cinereous vultures in south-eastern Europe while also being the location for substantial existing and planned wind farms. We used long-term remote telemetry data to produce a species-specific sensitivity map for guiding wind energy development and to estimate vulture collision mortality due to currently operating wind farms. Most operational wind farms were in the population core area and in the highest priority areas for vulture conservation. Collision mortality due to the thirteen operating wind farms was estimated by combining global position system (GPS) telemetry data on vulture space use with a collision risk model (CRM). Estimated mortality varied greatly according to the CRM's 'avoidance rate'. Under the most likely avoidance rates annual predicted collision mortality was 5-11% of the population, creating risk of population decline. Collision mortality was expected almost exclusively in the population core area, rendering further future development plans there severely problematic for vulture population persistence. Our sensitivity map, as a conservation prioritization system, offered a spatially explicit solution to the conflict between wind energy development and vulture conservation. Combining spatial use models derived from telemetry data with collision mortality models offers a novel conservation tool for evaluating large scale wind energy development proposals.