Abstract
Unsustainable fossil fuel emissions have prompted a global shift towards renewable energy sources, such as wind. This has led to a strong expansion of wind power generation infrastructures, often conflicting with biodiversity conservation. Relatively large flying animals, such as birds and bats, have frequently been reported to collide with wind turbines, resulting in casualties that can depress population size and lead to local extinctions. Migratory species that move across continents through their year-round displacements may be especially at risk. We comprehensively assessed wind turbine exposure for a colonial migratory raptor of European conservation interest, the lesser kestrel Falco naumanni, based on the distribution and size of >1800 colonies and a large GPS-tracking dataset (>350 individuals) for three distinct biogeographical populations (from Iberian, Italian, and Balkan peninsulas). 26 % of the European population has at least one wind turbine within the foraging areas around colony sites, Italian colonies being most at risk. The main European network of protected areas, the Natura 2000 network, failed to mitigate the potential negative impact of wind turbines on breeding populations. GPS-tracking revealed that exposure was negligible in the African non-breeding areas (Sahel region), particularly high during migration, and lower during breeding for Iberian and Balkan individuals but not for Italian ones. Different countries should prioritize different measures to mitigate collision risk with wind power generation infrastructures. This case study can be leveraged by conservationists and renewable energy stakeholders to mitigate conflicts between biodiversity conservation and expected wind energy infrastructure development in the near future.