Natal Dispersal and Recruitment of Two Bonelli's Eagles Aquila fasciata: a Four-Year Satellite Tracking Study

To study natal dispersal and recruitment to the breeding population in Bonelli’s Eagle, two nestlings were tagged with satellite transmitters in the Iberian Peninsula in 2002. Their monthly ranges and distances were computed and fitted to regression models to describe their general trend. One bird, a female, dispersed and settled rapidly in an area which she explored intensively during four years and which finally became her first breeding site. The natal dispersal distance was 441 km, and the bird cannot therefore be considered philopatric. The other bird, a male, alternated between long travelling episodes and settlement in particular areas, exploring different regions both distant from and close to his natal territory, but no breeding attempt could be confirmed after four years of tracking. The large distances we recorded confirm the potential for gene flow among populations but, in comparison with our results from previous studies, they suggest that Bonelli’s Eagles may show high variation in their natal dispersal distances and use different dispersal strategies.