Linking landscapes: analyzing corridors for bearded vultures in the Iberian Peninsula

Abstract The Bearded Vulture ( Gypaetus barbatus ) is listed in the Spanish Catalogue of Threatened Species as “Endangered.” Historically, it occupied mountainous regions across Asia, Europe, and Africa, and had a wide distribution throughout the Iberian Peninsula. However, its current presence in Spain is now limited to specific mountain ranges. The decline is due to various threats, including habitat loss, human disturbance, and poisoning, which necessitate targeted conservation efforts such as reintroduction and conservation programs. This study focuses on identifying potential ecological corridors and evaluating landscape connectivity for Bearded Vultures across key regions in Spain. Using environmental favourability models and a resistance-based approach (1/favourability) at a 10 × 10 km resolution, we generated maps of landscape connectivity and identified high- and low-connectivity areas. Corridors were delineated from areas of high connectivity and validated using GPS tracking data from tagged individuals. Our results reveal critical connectivity pathways in northern Spain, particularly linking Picos de Europa and the Pyrenees, influenced by topography, food availability, and distance to anthropogenic features. These findings emphasize the importance of maintaining functional corridors for the species and provide spatially explicit guidance for conservation planning to ensure long-term population viability.