Dispersal and survival of Aquila fasciata (Bonelli’s Eagle) differ across arid, semi-arid, and Mediterranean natal habitats

Dispersal is an important ecological process influencing population viability, demography, and gene flow. For non-migratory raptors like the Aquila fasciata (Bonelli’s Eagle), natal dispersal—the movement between the birthplace and the first breeding site—is a critical life stage. However, the role of natal habitat on the dispersal process and its implications for population viability and conservation remains poorly understood. This study examined how natal habitat across three distinct biogeographic regions influences dispersal movement, habitat use and survival of juvenile A. fasciata in the Levant (within areas administered by Israel and the Palestinian authority). Using global positioning system (GPS) telemetry, 55 juvenile eagles originating from Mediterranean, semi-desert, and desert habitats were tracked over their dispersal journeys. Key aspects such as dispersal direction, distance, temporary settlement areas (TSAs), territorial recruitment and mortality were analyzed in relation to the natal climatic conditions. Results revealed clear habitat-based differences in dispersal patterns. Desert-hatched eagles dispersed the farthest, with some crossing the Sahara and Arabian deserts to reach sub-Saharan Africa or southern Arabia, while Mediterranean and semi-desert eagles remained more localized. Water bodies acted as barriers, shaping dispersal routes and TSA distribution. Throughout dispersal, eagles occupied areas with precipitation levels similar to their natal sites, supporting natal habitat preference induction (NHPI) hypothesis. Recruitment data further indicated strong fidelity to natal climatic zones, with only 1 out of 11 eagles settling outside its natal zone. Mortality patterns varied by habitat types, with desert-hatched eagles experiencing the highest proportion of deaths outside the study area. These findings underscore the influence of natal habitat on dispersal, highlighting how local environmental conditions shape movement patterns, species distributions, and population trajectories. Understanding these patterns is crucial for raptor conservation, particularly in managing habitat-specific risks and transboundary movements.