IN FOCUS Santos, C. D., Silva, J. P., Muñoz, A.-R., Onrubia, A., & Wikelski, M. (2020). The gateway to Africa: What determines sea crossing performance of a migratory soaring bird at the strait of Gibraltar? Journal of Animal Ecology, 89, 1317-1328. Migrating birds undertake long journeys which pose several challenges. Water bodies are the most demanding ecological barriers for soaring birds, due to the increase in energy consumption and mortality risk. Through high-resolution GPS, Santos et al. (2020), analysed how the flight performance of 73 black kites crossing the Strait of Gibraltar was affected by external (e.g. weather conditions) and internal factors (individual experience). Kites waited for weaker crosswinds to start the crossing to minimize energy consumption, drift and altitude loss. Moreover, adults were quicker and lost less altitude than juveniles. These processes are likely to occur in all soaring species and have consequences also at a much wider spatial scale. In the Mediterranean region, species- and population-specific migration strategies appear to be influenced by interactions between species' morphology and the distribution of the land masses they traverse.

中文翻译：

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跨海是飞翔鸟类迁徙策略演变的主要决定因素

聚焦 Santos, CD, Silva, JP, Muñoz, A.-R., Onrubia, A., & Wikelski, M. (2020)。通往非洲的门户：是什么决定了直布罗陀海峡候鸟的跨海性能？动物生态学杂志，89，1317-1328。候鸟进行长途旅行，这带来了一些挑战。由于能源消耗和死亡风险的增加，水体是对飞翔鸟类最苛刻的生态屏障。通过高分辨率 GPS，Santos 等人。(2020), 分析了 73 只黑风筝穿越直布罗陀海峡的飞行性能如何受到外部 (如天气条件) 和内部因素 (个人经验) 的影响。风筝等待较弱的侧风开始穿越，以最大限度地减少能源消耗、漂移和高度损失。而且，与青少年相比，成虫速度更快，高度下降也更少。这些过程很可能发生在所有飙升的物种中，并且也会在更广泛的空间尺度上产生影响。在地中海地区，特定物种和特定种群的迁徙策略似乎受到物种形态与它们穿越的陆地分布之间相互作用的影响。