Turnover Dynamics in Two Patch-Tracking Sympatric Rail Metapopulations: Validating Inferences from Occupancy Data

这项研究考察了受威胁的黑铁和未受威胁的弗吉尼亚铁路在同一组湿地上表现出的不同的人口殖民和灭绝模式。这两种神秘的沼泽鸟类有着相似的自然历史，但根据存在-缺席调查得出的关系，它们飞往新地点的能力可能有很大不同。这项研究将回答两个主要问题：从在场-缺席数据中隐含的殖民模式是否与扩散行为相对应？当占用土地的比例保持不变时，人口流动率的相关性是否与入住率增加或下降时相同？通过调查加利福尼亚州塞拉山麓的许多小湿地，这项研究将：将根据周转率估计的扩散距离与根据遥测和遗传结构直接测量的距离进行比较；跟踪最近西尼罗河病毒造成的灭绝事件后斑块的殖民；使用基因和同位素措施确定殖民者的来源，以理清短距离和长距离扩散的贡献；并通过检测所有捕获的铁路的血液来监测西尼罗河病毒的复发。这项研究产生的更广泛的影响将是开发与土地所有者合作的技术，以支持保护其土地上的稀有物种。私人土地支持不成比例的濒危物种，关于根据《濒危物种法》保护物种的争议也在发生。很少有关于私有财产的实地研究。这项研究提供了一个独特的机会，以探索与私人土地所有者合作的方式，并通过各种方法进行教育推广。该项目将通过培训研究生和本科生，并为当地土地所有者、奥杜邦志愿者、高中生和教师提供与研究人员一起体验该领域研究的机会，将研究与教育相结合。该项目的成果将通过产生有关地区人口扩散能力和连通性的重要数据，并为管理专门为加州增长最快的地区之一的黑轨创建的湿地提供信息，从而促进黑轨的保护。

This study examines differing patterns of population colonization and extinction exhibited by the threatened black rail and the non-threatened Virginia rail inhabiting the same set of wetlands. These two cryptic marsh birds have similar natural histories, but may differ greatly in their ability to fly to new sites based on relationships derived from presence-absence surveys. This study will answer two main questions: Do the patterns of colonization implied from presence-absence data correspond to dispersal behavior? Are the correlates of population turnover the same when the proportion of sites occupied remains constant as when occupancy is increasing or declining? By surveying numerous small wetlands in the Sierra Foothills of California, this research will: compare dispersal distances estimated from turnover to direct measures from telemetry and genetic structure; track colonization of patches after recent extinction events caused by West Nile virus; determine the origin of colonists using genetic and isotope measures to untangle the contributions of short- and long-distance dispersal; and monitor for reoccurrence of West Nile virus by testing blood of all captured rails. A broader impact resulting from this research will be the development of techniques for working with landowners to support conservation of rare species on their land. Private land supports a disproportionate percentage of endangered species and controversies concerning the protection of species under the Endangered Species Act occur. Few field studies are conducted on private property. This study provides a unique opportunity to explore ways of working with private landowners, and for educational outreach through a variety of approaches. The project will integrate research and education by training graduate and undergraduate students, and by offering local landowners, Audubon volunteers, high school students and teachers the chance to experience research in the field with researchers. Results from this project will advance Black Rail conservation by producing important data on dispersal ability and connectivity among regional populations, and informing management of wetlands created specifically for black rails in one of the most rapidly growing regions of California.