Migration distance is a fundamental axis of the slow-fast continuum of life history in boreal birds

Seasonal migration is intrinsically connected to the balance of survival and reproduction, but whether migratory behavior influences species’ position on the slow-fast continuum of life history is poorly understood. We found that boreal-breeding birds that migrate long distances exhibit higher annual adult survival and lower annual reproductive investment relative to co-distributed boreal species that migrate shorter distances to winter closer to their breeding grounds. Our study uses “vital rates” data on reproductive output and survivorship compiled from the literature for a species assemblage of 45 species of mostly passerine birds. These species breed sympatrically in North American boreal forests but migrate to a diversity of environments for the northern winter. After controlling for body size and phylogeny, migration distance and apparent annual adult survival are positively related across species. Both migration distance and survival are positively correlated with wintering in e...

季节性迁徙与物种存活和繁殖的平衡存在内在关联，但迁徙行为是否会影响物种在生命史快慢连续体上的位置，目前仍鲜有明确结论。我们发现，相较于同域分布的寒带繁殖鸟类（此类鸟类迁徙距离更短，会在距离繁殖地较近的区域越冬），长距离迁徙的寒带繁殖鸟类具有更高的成年年存活率，同时年度繁殖投入更低。本研究通过文献汇编获取了以雀形目（passerine）鸟类为主的45个物种种群的繁殖产出与存活数据，即“生命率（vital rates）”。这些鸟类均在北美寒带森林中同域繁殖，但会迁徙至多样环境中度过北方冬季。在控制体型大小与系统发育（phylogeny）的影响后，跨物种的迁徙距离与表观成年年存活率呈显著正相关。迁徙距离与存活率均与在[原文未完整呈现的越冬环境类型]越冬呈正相关。