LTREB: Stopover Biology of Intercontinental Landbird Migrants

从帝王蝶到座头鲸，迁徙是许多动物生命史的一个基本特征，也是所有行为中最迷人的一种。在北美温带繁殖的鸣禽中，超过三分之二的鸣禽长途迁徙到墨西哥、中美洲和南美洲以及加勒比岛屿的越冬地区。长途旅行有相当大的风险，死亡率可能很高。本研究主要关注候鸟在暂停休息和补充能量时所面临的问题：除了飞行的能量消耗外，候鸟总是发现自己在能量需求高的时候处于陌生的环境中，经常面临躲避捕食者和寻找食物，与其他候鸟和留鸟竞争有限的资源，面临不利的天气，以及需要纠正方向错误。实地研究旨在确定移民在穿越墨西哥湾之前和之后如何解决这些问题。除了更好地了解动物对能量需求时期的反应外，这项研究还具有重要的保护意义。有证据表明，在过去的25年里，许多候鸟物种的数量都在下降。尽管关于大熊猫数量减少的原因的争论仍在继续，但在制定保护计划的过程中，人们在很大程度上忽视了栖息地在迁徙过程中的重要性。除非满足迁徙期间对栖息地的要求，否则以繁殖地和/或热带越冬地区为重点的保护措施将受到损害。我们对候鸟如何应对中途停留栖息地的可用性和分布的变化知之甚少。

Migration is a fundamental characteristic of the life history of many animals from monarch butterflies to humpback whales and is one of the most fascinating of all behavior. Over two-thirds of all songbirds that breed in temperate North America migrate long distances to wintering areas in Mexico, Central and South America and the Caribbean islands. Traveling long distances comes with considerable risks, and the mortality may be substantial. This research focuses on the problems migrants face when they pause to rest and refuel: Besides the energetic cost of flying, a migratory bird invariably finds herself in unfamiliar surroundings at a time when energy demands are high, often faced with avoiding predator avoidance and finding food, competing with other migrants and resident birds for limited resources, faced with unfavorable weather, and the need to correct orientation errors. Field studies are designed to determine how migrants solve these problems before and after crossing the Gulf of Mexico.Besides gaining a better understanding of how animals respond to periods of energetic demand, this research has important conservation implications. Evidence reveals population declines among many migratory bird species over the past quarter century. Although debate over the causes of the decline continues, what has been largely overlooked in development of conservation plans is the importance of habitat during migration. Unless habitat requirements during migration are met, conservation measures focused on the breeding grounds and/or tropical wintering areas will be compromised. We know little about how migratory birds respond to changes in the availability and distribution of stopover habitat.