Dispersal Ecology of Golden Eagles (Aquila chrysaetos) in Northern Greece: Onset, Ranging, Temporary and Territorial Settlement

Abstract

Natal dispersal is a crucial period for raptors with serious implications for individuals’ survival and population demography. In this study we analyzed data from 18 GPS-tracked golden eagles in order to describe their dispersal ecology in northern Greece, where the species feeds mostly on tortoises. Young eagles in our population dispersed at 176 days post fledging, spent their first year of independence relatively close (40–60 kms) to their natal ranges and exhibited a variable temporary settlement behavior. Overall dispersal range sizes did not differ seasonally, but temporary settlement area range sizes were significantly larger in winter. Three eagles survived to territorial settlement and occupied ranges 20–60 kms from their natal areas. The application and refinement of the Scottish GET dispersal ranging model suggested that eagles used areas that had higher topographical relief and lower canopy cover during their natal dispersal. Habitat heterogeneity seems to also be influential during temporary settlement. Our study is the first to provide both such insights for golden eagles in southern eastern Europe and a method for delineating temporary settlement areas for the species. Our findings can be explained in terms of food and habitat availability. We highlight the importance of conserving heterogeneous open areas of complex topography and applying proactive management measures within temporary settlement areas for our population’s conservation.