Collaborative Research: Population Limitation of Neotropical Migratory Birds and the Seasonal-Interaction Hypothesis

0089565 Marra了解小型迁徙动物的生物学受到跟踪个体和全年整合生态影响的困难的阻碍。这里提出的工作涉及两种候鸟的季节性联系。 这项研究将测试的假设，繁殖成功取决于栖息地质量占据在以前的热带冬季期间相比，传统的替代方案，繁殖条件单独的问题。冬季栖息地的签名将被确定在繁殖鸟类使用稳定的碳同位素血液组织采样。 繁殖成功率将根据冬季栖息地占用模式和繁殖领土质量和个人条件的指数进行测量和评估。 冬季食物调控将评估冬季栖息地质量与繁殖事件之间的联系机制。候鸟的丰富和多样性构成了一种壮观的自然现象。 这些物种控制害虫，通过种子传播和授粉改变植物群落，并稳定人类赖以生存的生态系统。 这项研究将为候鸟的数量是如何全年限制和调节的提供新的基本见解，从而帮助更准确地构建季节性联系的种群模型。 种群模型对于理解这些动物对人类对全球栖息地数量、质量和气候变化的影响的反应至关重要。

0089565 MarraUnderstanding the biology of small migratory animals is hampered by the difficulties involved in tracking individuals and integrating ecological impacts year-round. The work proposed here addresses seasonal linkages in two migratory bird species. This study will test the hypothesis that reproductive success depends on habitat quality occupied in the prior tropical winter period in contrast to the conventional alternative that breeding conditions alone matter. Winter habitat signatures will be identified in breeding birds using stable carbon isotopes sampled in blood tissue. Reproductive success will be measured and assessed according to winter habitat occupancy patterns and to indices of breeding territory quality and individual condition. Food manipulations in winter will assess the mechanisms linking habitat quality in winter to breeding events.The abundance and diversity of migratory birds comprise a spectacular natural phenomenon. Such species control insect pests, modify plant communities via seed dispersal and pollination, and stabilize ecosystems upon which humans depend. This research will contribute fundamental new insights into how the abundance of migratory birds is limited and regulated year-round, thereby helping structure seasonally linked population models more accurately. Population models are crucial to understand these animals' responses to human impacts on global habitat quantity, quality, and climate change.