Movements of Cyprus Wheatear Oenanthe cypriaca fledglings: evidence of a post-fledging home range away from the natal site prior to first migration

Abstract

Dispersal to efficiently locate future breeding areas in young animals has important consequences for survival, life history and future breeding success, and therefore population dynamics and evolution. Long-distance migrant birds that have little time immediately pre-breeding may use the post-fledging period to locate their future breeding territory. We radio-tracked 37 juvenile Cyprus Wheatears, Oenanthe cypriaca, a long-distance migrant passerine, to investigate movements for 10 weeks post-fledging. We measured how distance from the nest and distance of consecutive movements changed with age. We tested whether distance from the nest stopped increasing and consecutive movement distance became similar to pre-dispersal distances, consistent with a fledgling adopting a post-fledgling home range that could reflect scoping out a future local breeding territory. Fledglings had a very high survival rate. Directed movements away from the natal territory started at about 18 days until about 45 days when individuals adopted a more fixed location on average about 600 m (range 0–1500) from their natal site, and further movements were at a scale equivalent to movements within an adult-sized breeding territory. Our results suggest dispersal followed by settlement in a fixed home range prior to first migration that could function to identify the breeding site location for the following year.