Physiological mechanisms of migratory traits

这一建议的重点是白冠麻雀的春季和秋季迁徙。本研究的主要目的是确定调节迁徙特征的生理机制以及鸟类在准备和完成每次迁徙时所依赖的环境信号。虽然春季和秋季的迁徙距离相同，但这些迁徙的其他方面都是不同的，鸟类已经进化出不同的策略来成功完成每一次迁徙。潜在的生理基础尚未得到严格的调查，研究者认为，由于环境的显著变化和栖息地的丧失，许多移民人口正在迅速减少，因此对这些机制的理解日益受到关注。拟议的研究利用了白冠麻雀的两个亚种，一种是长途迁徙的，另一种是不再迁徙的，是常驻的。研究者建议研究1)当一个亚种准备春季迁徙而另一个亚种不准备春季迁徙时，两个亚种在肌肉发育和脂肪储存方面的差异；2)春季和秋季迁徙的不同激素机制；3)雏鸟和成鸟在秋季迁徙准备方面的差异。这项研究的结果可能为调控迁移的机制提供新的见解，同时指导进一步的研究，以确定影响迁移群体潜在成功或失败的细胞基础。该项目将支持一名博士后研究员、一名研究生和几名本科生助理。在加州和阿拉斯加，通过调查员和SLEWS（学生和土地所有者教育流域管理）项目之间建立的合作，向公众进行宣传，SLEWS项目分别与奥杜邦农场和陆地学习中心以及阿拉斯加鸟类观测站有关。

This proposal focuses on both spring and fall migrations of White-crowned Sparrows. The primary goal of this research is to determine the physiological mechanisms regulating migratory traits and the environmental signals birds rely upon for preparation and completion of each journey. Although spring and autumn migrations cover the same distance, all other facets of these trips are different and birds have evolved distinct strategies to complete each successfully. The underlying physiological bases have as yet to be rigorously investigated and the investigator posits that understanding these mechanisms is of growing concern as many migrant populations are declining rapidly owing to marked changes in the environment and loss of habitat. The proposed studies take advantage of two sub-species of White-crowned Sparrow, one that migrates long distances and one that no longer migrates and is resident. The investigator proposes to examine 1) the differences in muscle development and fat storage in the two subspecies as one prepares for spring migration and the other does not; 2) the different hormonal mechanisms involved in the spring and fall migrations, and 3) differences in preparation for the fall migration between young and adult birds. Results from this study may offer new insights into the mechanisms regulating migration while directing further investigations to define the cellular bases that influence the potential success or failure of a migratory population. The project would support a postdoctoral researcher, a graduate student and involve several undergraduate assistants. Outreach to the public would occur in California and Alaska through established collaborations between the investigator and the SLEWS (student and landowner education watershed stewardship) program associated with the Audubon Farm and Center for Land-based Learning and the Alaska Bird Observatory, respectively.