Tracing origins and nutrient allocations in migrating birds and insects using compound-specific isotope techniques

候鸟、昆虫和其他动物经常在它们的年度周期中在大陆之间长途迁徙。这对有效保护和了解影响其生存和成功繁殖的因素提出了巨大挑战。饮食和营养在决定迁徙动物的成功方面起着至关重要的作用，因为迁徙动物需要为数百或数千公里的旅程提供燃料。在这些旅行中，动物经常需要在关键地点停留，以便休息和补充燃料。在到达目的地的过程中，它们经常遇到完全不同的食物网，需要相应地调整饮食和觅食。为了繁殖而旅行的迁徙者也能够携带营养物质，最终可以转移到他们的后代身上，而其他生物，如迁徙的帝王蝶，需要带着足够的脂肪储备到达墨西哥的越冬地，以度过冬季禁食期。 重要的是要追踪营养途径对迁移生物的重要性。这些知识将通过确定营养来源的关键栖息地，使加拿大人能够更明智地保护对加拿大人重要的野生动物。预期的信息还将帮助我们评估移民对当前和预期全球变化的敏感性。我已经开发出使用食物网中自然存在的指纹，即（几种元素的）稳定同位素，来追踪野生鸟类和昆虫中营养素的来源和使用。我目前的建议是将这一研究领域提升到一个新的水平，从分析羽毛等大块组织进入单个氨基酸和脂质的领域。这将允许更精确的追踪，并遵循最近在这一领域的突破，基于发现单个化合物中的同位素比率可以提供更精确的营养级和摄食来源的信息。这项建议将支持研究生论文项目，以检查氨基酸的使用（主要是谷氨酸和苯丙氨酸）和全脂质稳定同位素分析作为指纹图谱来评估1）候鸟长期饮食重建（画眉和滨鸟），2）迁徙昆虫用于越冬生存的储存脂质储备的来源;储存的营养与当地获得的营养对鸟类繁殖的贡献。

Migratory birds, insects and other animals often move over vast distances and between continents during their annual cycles. This presents immense challenges for their effective conservation and understanding of the factors influencing their survival and successful reproduction. Diet and nutrition play a fundamental role in determining the success of migratory animals because migrants need to fuel their journeys which may be hundreds or thousands of kilometers. During these travels, animals often need to stopover at key sites where they can rest and refuel. In reaching their destinations, they often encounter entirely different foodwebs and need to adjust their diets and foraging accordingly. Migrants that travel to breed also are able to carry nutrients with them that ultimately can be transferred to their offspring while other organisms like migratory Monarch Butterflies need to arrive on their wintering grounds in Mexico with enough fat reserves to last them through the winter fasting period. It is important to trace the importance of nutrient pathways to migratory organisms. Such knowledge will allow much more informed conservation of wildlife important to Canadians by identifying critical habitats where nutrients are derived. The anticipated information will also help us assess the susceptibility of migrants to current and anticipated global change. I have developed the use of naturally occurring fingerprints in foodwebs known as stable isotopes (of several elements) to trace origins and use of nutrients in wild birds and insects. My current proposal is to move this area of research to a new level, from analyses of bulk tissues like feathers into the realm of individual amino acids and lipids. This will allow more precise tracing and follows from recent breakthroughs in this field based on the discovery that isotope ratios in individual compounds can provide more precise information of trophic level and source of feeding. This proposal will support graduate thesis projects to examine the use of amino acid (primarily glutamate and phenylalanine) and whole lipid stable isotope analyses as fingerprints to evaluate 1) long-term dietary reconstruction in migratory birds (thrushes and shorebirds), 2) origins of stored lipid reserves used by migratory insects for overwinter survival and 3) contributions of stored vs. locally acquired nutrients for reproduction in birds that travel to breed.