Department of Migration, Max Planck Institute of Animal Behavior, Radolfzell, Germany.
Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany.
Ecol Lett. 2021 Jul;24(7):1432-1442. doi: 10.1111/ele.13763. Epub 2021 May 11.
Dispersal is a critical, but costly, stage of life. During the active phase of dispersal-called transience-individuals face many costs, from increased mortality to reduced foraging opportunities. One cost that is often assumed, but rarely explicitly tested, is the energy expended in making large dispersal movements. However, this cost is not only determined by the distance individual's move, but also how they move. Using high-resolution GPS tracking of dispersing and resident vulturine guineafowl (Acryllium vulturinum), we show that transient individuals exhibit distinct movement behaviours-travelling farther, faster and straighter-that result in a significant reduction in the energetic costs of making large displacements. This strategy allows dispersing birds to travel, on average, 33.8% farther each day with only a 4.1% cost increase and without spending more time moving. Our study suggests that adaptive movement strategies can largely mitigate movement costs during dispersal, and that such strategies may be common.
扩散是生命中一个关键但代价高昂的阶段。在扩散的活跃阶段——称为易逝性——个体面临许多代价，从死亡率增加到觅食机会减少。有一种代价通常被假设，但很少被明确测试，那就是在进行大规模扩散运动中消耗的能量。然而，这种成本不仅取决于个体移动的距离，还取决于他们的移动方式。通过对正在扩散和居住的秃鹫（Acryllium vulturinum）进行高分辨率 GPS 跟踪，我们发现易逝性个体表现出明显的运动行为——移动得更远、更快、更直——这导致在进行大规模位移时能量成本显著降低。这种策略使扩散鸟类平均每天能够多移动 33.8%，而能量成本仅增加 4.1%，且无需花费更多时间移动。我们的研究表明，适应性的运动策略可以在很大程度上减轻扩散过程中的运动成本，并且这种策略可能很常见。
