Dispersal, maturation and recruitment in a long-lived, intercontinental migrant bird

Natal dispersal is a multistep process. It commences when a juvenile departs from its natal site and concludes when it settles to breed for the first time. During this interim period, dispersing individuals of long-lived species often undergo a wandering phase, which may span years. This phase remains one of the least studied aspects of avian life histories. We utilized a unique GPS-telemetry data set on a slow-reproducing, long-lived migratory bird of prey, the European honey buzzard, Pernis apivorus , tracked for up to 6 years after fledging. Our aim was to assess how phenology, ranging behaviour and philopatry change as individuals gain experience. Individuals exhibited variability in the age at which they first returned to their breeding range, yet all survivors settled at sites proximate to their natal nests. In subsequent returns, immatures increased the time spent within the breeding range and narrowed down their ranging to smaller areas situated progressively closer to their natal nests. Our study reveals the complexity and extended nature of natal dispersal, emphasizing the importance of individual experience and migratory improvement for successful recruitment in long-lived species. • We used GPS data to track natal dispersal and recruitment in honey buzzards. • Birds reduced range, approached natal sites and aligned with adult timing over time. • High mortality during return migration acted as a bottleneck prior to recruitment. • Natal dispersal was protracted and linked to variation in age of first return.