Dissertation Research: Modeling Winter Food Limitation in a Migratory Bird

迁徙鸣禽的种群数量受到多种环境和生态因素的限制。 在越冬地、繁殖地和迁徙过程中发生的事件都可能影响它们的种群规模。目前，控制候鸟种群的生态机制知之甚少。 基于证据的生态相关性表明，食物丰富可能是最重要的冬季因素限制迁徙鸣禽的人口，但是，没有发表的实验证据支持这一假设的移民在温带或热带越冬地区。 使用烤箱鸟（Seiurus aurocapillus）越冬在牙买加，我们正在研究如何实验操作的食物供应影响的行为，生理，生存和迁移出发时间的迁徙鸣禽。 基于这些实验和观测研究得出的估计，我们将构建一个模拟模型，以研究人口如何应对气候变化，气候变化通过降雨量的变化影响食物丰富度。 模型预测将通过将鸟类繁殖调查数据测量的炉鸟种群的长期大陆规模变化与整个炉鸟冬季分布的气候和植被模式的历史记录相关联来进行测试。 我们采取了一种独特的方法，通过使用模拟建模来连接小规模的，基于实地的实验测试的机制，限制候鸟种群与有据可查的大规模变化的人口规模的广泛分布的北美候鸟物种。

Populations of migratory songbirds are limited by multiple environmental and ecological factors. Events occurring on the wintering grounds, the breeding grounds, and during migration all potentially affect their population size. Currently, the ecological mechanisms that control populations of migratory birds are poorly understood. Evidence based ecological correlations suggests that food abundance may be the most important winter-season factor limiting populations of migratory songbirds; however, no published experimental evidence exists to support this hypothesis for migrants in temperate or tropical wintering areas. Using the Ovenbird (Seiurus aurocapillus) wintering in Jamaica, we are investigating how experimental manipulations of food availability affect the behavior, physiology, survival, and migration departure timing of a migratory songbird. Based on estimates derived from these experimental and observational studies, we will construct a simulation model to investigate how populations may respond to climate change, which affects food abundance via patterns of changing rainfall. Model predictions will be tested by correlating long-term, continental-scale changes in Ovenbird populations, as measured by Breeding Bird Survey data, with historical records of climate and vegetation patterns from across the Ovenbird's winter distribution. We take a unique approach by using simulation modeling to link small-scale, field-based experimental tests of the mechanisms that limit migratory bird populations with well documented large-scale changes in population size of a widely distributed North American migratory bird species.