Finish with a sprint: evidence for time‐selected last leg of migration in a long‐distance migratory songbird

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 a race among individuals where winners are arriving first when conditions are suitable. The sprint migration hypothesis predicts that individuals shift from maximum sustained speed to a final burst of sprint to shorten the transition from migration to breeding (Alerstam, 2006). In this study, we test the hypothesis of a final sprint migration in a long‐distance Afro‐Palearctic migrant, the collared flycatcher Ficedula albicollis, during autumn and spring, and compare migration strategies between the seasons. In both seasons, collared flycatchers evidently exhibited sprint migration by increasing their overall speed over the last leg of migration after the Sahara crossing. This phenomenon was more pronounced in spring, contributing to overall faster spring migration and possibly highlighting higher importa...

在时间选择型迁徙（time-selected migration）情境下，鸟类需演化出竞争策略以击败同类、优先获取最终目的地的优质资源。因此，迁徙可被视为个体间的一场竞赛：当环境条件适宜时，率先抵达者即为赢家。冲刺迁徙假说（sprint migration hypothesis）预测，个体将从维持最高持续飞行速度，转为发起最终冲刺，以缩短迁徙至繁殖的过渡阶段（Alerstam, 2006）。本研究以长距离非洲-古北界（Afro-Palearctic）迁徙鸟类——领捕蝇鶲（Ficedula albicollis）为研究对象，分别在春秋两季验证其存在最终冲刺迁徙的假说，并对比两季的迁徙策略差异。春秋两季中，领捕蝇鶲均表现出冲刺迁徙特征：在穿越撒哈拉沙漠后的最后一段迁徙路程中，其整体飞行速度显著提升。该现象在春季更为显著，助推春季整体迁徙速度更快，也可能凸显出春季迁徙的更高重要性……