Laboratorio de Biología Evolutiva de Vertebrados, Departamento de Ciencias Biológicas, Universidad de los Andes, Bogotá, Colombia.
SELVA: Investigación para la conservación en el Neotropico, Bogotá, Colombia.
Sci Rep. 2017 Jun 13;7(1):3405. doi: 10.1038/s41598-017-03503-4.
Long-distance migratory organisms are under strong selection to migrate quickly. Stopovers demand more time than flying and are used by individuals to refuel during migration, but the effect of fuel loads (fat) acquired at stopover sites on the subsequent pace of migration has not been quantified. We studied stopover behaviour of Grey-cheeked Thrush (Catharus minimus) at a site in northern Colombia and then tracked their migration using an intercontinental radio-telemetry array. Tracking confirmed long-distance flights of more than 3000 km, highlighting the key importance of a single stopover site to the migration strategy of this species. Our results suggest that these songbirds behave as time-minimizers as predicted by optimal migration theory, and that fuel loads acquired at this South American stopover site, together with departure date, carry-over to influence the pace of migration, contributing to differences in travel time of up to 30 days in birds subsequently detected in the U. S. and Canada. Such variation in the pace of migration arising from a single stopover site, likely has important fitness consequences and suggests that identifying important fuelling sites will be essential to effectively conserve migratory species.
长距离迁徙生物受到快速迁徙的强烈选择。中途停留需要更多的时间，而不是飞行，并且个体在迁徙过程中利用这些停留点来加油，但在中途停留点获得的燃料（脂肪）负载对随后的迁徙速度的影响尚未量化。我们在哥伦比亚北部的一个地点研究了灰颊山雀（Catharus minimus）的中途停留行为，然后使用洲际无线电遥测阵列追踪它们的迁徙。追踪确认了超过 3000 公里的长距离飞行，突出了这个物种迁徙策略中单一个中途停留点的关键重要性。我们的结果表明，这些鸣禽的行为表现符合最优迁徙理论预测的时间最小化者，并且在南美洲中途停留点获得的燃料负载以及出发日期，会影响迁徙速度，导致在美国和加拿大检测到的鸟类的旅行时间差异高达 30 天。这种由单个中途停留点引起的迁徙速度的变化可能具有重要的适应性后果，并表明确定重要的加油地点对于有效保护迁徙物种至关重要。
