Finish with a sprint: Evidence for time-selected last leg of migration in a long-distance migratory songbird.

摘要: Under time-selected migration, birds should choose a strategy for outcompeting rivals over securing access to prime resources at the final destination. Thus, migration can be viewed as race among individuals where winners are arriving first when conditions suitable. The sprint hypothesis predicts that shift from maximum sustained speed burst of shorten transition breeding (Alerstam, 2006). In this study, we test in long-distance Afro-Palearctic migrant, collared flycatcher Ficedula albicollis, during autumn and spring, compare strategies between seasons. both seasons, flycatchers evidently exhibited by increasing their overall last leg after Sahara crossing. This phenomenon was more pronounced contributing faster spring possibly highlighting higher importance early arrival grounds. seasons particularly late departing flew rate, partially being able catch up with conspecifics. Differential fueling may play an important role determining speed, especially stages might explain observed differences speeds individuals. Our findings suggest competition nonbreeding destinations alike. Sprint appropriate gain advantage conspecifics settle territories well cope increasingly earlier springs high latitudes.