How Environment, Physiology and Life History Interact to Determine Pattern in Animal Migration

动物迁徙也许是地球上最壮观的生态现象。无论是每年在两极之间航行的微小北极燕鸥，还是顽强地穿越非洲塞伦盖蒂平原的数百万头角马，迁徙都比其他生物事件更能激发人们的想象力。然而，尽管移民具有重要的生态意义和文化意义，但人们对其科学的了解仍然很少。即使是动物为什么、何时、何地、谁以及如何迁徙等基本问题，在很大程度上也没有答案。例如，为什么一只600磅重的巨型乌龟——一种可以在没有食物或水的情况下轻松生存一年或更长时间的大型爬行动物——会季节性地在加拉帕戈斯群岛布满熔岩的火山斜坡上上下迁徙？为什么只有成年人迁徙？为什么有些岛屿上的陆龟几乎不动？巨龟是理解动物迁徙的一种可操作的“模型”，因为在一个小的地理区域内，许多不同的物种在非常不同的环境条件下进化而来。在这个项目中，一套研究方法，包括幼龟和成年龟的GPS遥测，将被用来追踪加拉帕戈斯龟的活动。龟的健康，包括接触传染病、寄生虫感染和压力水平，将通过血液和粪便样本进行研究，而传统的实地工作将衡量迁徙个体与非迁徙个体的生殖成功率。这个项目将回答一些关于所有动物运动生态学的基本问题，而不仅仅是巨龟。在一个由于人类活动而迅速变化的世界中，了解动物迁徙是预测哪些动物将受到最大影响并为它们制定管理计划的关键。由于迁徙动物可能是影响人类和农业的疾病的重要媒介，这项工作的意义超出了野生动物。最后，所有的结果将被打包成一个令人兴奋的推广计划，目的是激励和教育加拉帕戈斯群岛和美国的孩子们对生态科学和保护战略有更强的认识。

Animal migration is perhaps the most spectacular ecological phenomenon on Earth. Be it tiny Arctic terns navigating annually between the poles, or millions of wildebeest doggedly traversing the Serengeti plains of Africa, migration captures the imagination of people like few other biological events. Yet despite its ecological importance and cultural significance, the science of migration remains poorly understood. Even basic questions about why, when, where, who and how animals migrate are largely unanswered. Why, for example, would a 600 pound giant tortoise -- a large reptile that can easily survive for a year or more without food or water -- migrate seasonally up and down the lava strewn volcanic slopes of the Galapagos Islands? Why is it that only adults migrate? And why do tortoises on some islands barely move at all? Giant tortoises represent a tractable "model" for understanding animal migration because many distinct species have evolved under very different environmental conditions within a small geographical area. In this project, a suite of research methods, including GPS telemetry of both young and adults will be used to track Galapagos tortoise movements. Tortoise health, including exposure to infectious diseases, parasite infection and stress levels, will be studied through blood and dung samples, while traditional field work will measure reproductive success of migratory versus non-migratory individuals. This project will answer some of the fundamental questions underpinning movement ecology in all animals, not just giant tortoises. In a world that is rapidly changing due to human activities, understanding animal migration is key to predicting which animals will be most affected and devising management plans for them. Because migratory animals can be important vectors of diseases that impact humans and agriculture, the significance of this work extends beyond wildlife. Finally, all results will be packaged into an exciting outreach program with the aim of inspiring and educating children in both Galapagos and the USA toward a stronger appreciation of ecological sciences and strategies of conservation.