Ecological and physiological correlates of migration and dispersal in birds

我将研究与迁徙雀鸟源种群与汇种群维持相关的栖息地特征。这将涉及使用稳定同位素标记（主要是氘，碳-13，氮-15）和羽毛中的微量元素谱作为以前繁殖或出生位置的测量。鸟类羽毛是用来代替位置的理想材料，因为它们是在已知的生命周期时期生长的，并且保持了来源的同位素特征。通过研究个体群体羽毛中的同位素特征，可以推导出这些群体作为本地和更远距离分散者的组成。最佳的森林立地将是大面积的连续的北方森林，而贫瘠的森林将是被农业包围的孤立的森林碎片。因此，将测试生境质量在立地哲学和扩散中的作用。第二个主要研究领域将是调查影响几种高北极地区不同体型筑巢鸟类（大型水禽和小型涉禽）内源性脂质和蛋白质储备相对投入繁殖的因素。稳定同位素是直接追踪营养来源的有力工具。我的新研究将通过测试加拿大北极地区不同纬度梯度的滨鸟在不同春季条件下的收入与资本策略的可塑性来进一步探讨这个问题。

I will investigate habitat characteristics associated with the maintenance of source vs. sink populations of migratory passerine birds. This will involve the use of stable isotope markers (primarily deuterium, carbon-13, nitrogen-15) and trace-element profiles in feathers as measures of previous breeding or natal location. Bird feathers represent ideal material to use as proxies for location since they are grown during known periods of the life cycle and maintain isotopic signatures of source. By investigating the isotopic signatures in feathers of populations of individuals, the composition of those populations as local vs. more long-distance dispersers can be derived. Optimal forest sites will be contiguous boreal forest tracts of large extent and poor forest will be isolated forest fragments surrounded by agriculture. Thus, the role of habitat quality in site philopatry and dispersal will be tested. The second primary area of research will be the investigation of factors influencing the relative input of endogenous lipid and protein reserves into reproduction in several species of high-Arctic nesting birds varying in body size (large-bodied waterfowl through small-bodied waders). Stable isotopes represent a powerful tool to trace origins of nutrients directly. My new research will pursue this question further by testing the plasticity of the income vs. capital strategy in shorebirds subjected to different spring conditions across a latitudinal gradient in the Canadian Arctic.