Kürten Nathalie, Schmaljohann Heiko, Bichet Coraline, Haest Birgen, Vedder Oscar, González-Solís Jacob, Bouwhuis Sandra
Institute of Avian Research, An der Vogelwarte 21, 26386, Wilhelmshaven, Germany.
Institute of Biology and Environmental Sciences, University of Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26129, Oldenburg, Germany.
Mov Ecol. 2022 Feb 5;10(1):5. doi: 10.1186/s40462-022-00303-y.
Understanding the evolution of migration requires knowledge of the patterns, sources, and consequences of variation in migratory behaviour, a need exacerbated by the fact that many migratory species show rapid population declines and require knowledge-based conservation measures. We therefore need detailed knowledge on the spatial and temporal distribution of individuals across their annual cycle, and quantify how the spatial and temporal components of migratory behaviour vary within and among individuals.
We tracked 138 migratory journeys undertaken by 64 adult common terns (Sterna hirundo) from a breeding colony in northwest Germany to identify the annual spatiotemporal distribution of these birds and to evaluate the individual repeatability of eleven traits describing their migratory behaviour.
Birds left the breeding colony early September, then moved south along the East Atlantic Flyway. Wintering areas were reached mid-September and located at the west and south coasts of West Africa as well as the coasts of Namibia and South Africa. Birds left their wintering areas late March and reached the breeding colony mid-April. The timing, total duration and total distance of migration, as well as the location of individual wintering areas, were moderately to highly repeatable within individuals (repeatability indexes: 0.36-0.75, 0.65-0.66, 0.93-0.94, and 0.98-1.00, respectively), and repeatability estimates were not strongly affected by population-level inter-annual variation in migratory behaviour.
We found large between-individual variation in common tern annual spatiotemporal distribution and strong individual repeatability of several aspects of their migratory behaviour.
了解迁徙的演变需要掌握迁徙行为变化的模式、来源和后果，而许多迁徙物种数量迅速下降，需要基于知识的保护措施，这一需求变得更加迫切。因此，我们需要详细了解个体在其年度周期中的时空分布，并量化迁徙行为的时空组成部分在个体内部和个体之间是如何变化的。
我们追踪了64只成年普通燕鸥（Sterna hirundo）从德国西北部一个繁殖地出发的138次迁徙旅程，以确定这些鸟类的年度时空分布，并评估描述其迁徙行为的11个性状的个体重复性。
鸟类于9月初离开繁殖地，然后沿着东大西洋飞行路线向南移动。9月中旬到达越冬地，位于西非的西海岸和南海岸以及纳米比亚和南非的海岸。鸟类于3月下旬离开越冬地，4月中旬到达繁殖地。迁徙的时间、总持续时间和总距离，以及个体越冬地的位置，在个体内部具有中等至高度的重复性（重复性指数分别为：0.36 - 0.75、0.65 - 0.66、0.93 - 0.94和0.98 - 1.00），并且重复性估计不受种群水平迁徙行为年际变化的强烈影响。
我们发现普通燕鸥年度时空分布存在较大的个体间差异，并且其迁徙行为的几个方面具有很强的个体重复性。
