Detecting Cryptic Exposure and Effects of Neurotoxic Insecticides to Migratory Birds

许多候鸟和与农田有关的鸟类在北美各地都出现了急剧的数量下降。其中一个主要的假定原因是农药对利用农业景观的鸟类的影响。在过去的35年里，北美的传统农业实践增加了对农用化学品的依赖，以在高度简化的土地上维持或提高产量。候鸟和与农田有关的鸟类可能通过摄入处理过的种子或颗粒、喷洒过的土壤或被污染的猎物和水而暴露于有毒杀虫剂。由于鸟类迁徙是一个复杂的过程，需要整合多感官信息才能成功地定位和导航，并在中转站快速补充燃料，即使是杀虫剂暴露引起的微妙、潜伏的扰动也可能延迟鸟类的迁徙，改变它们的路线，减少它们的生存和繁殖机会。然而，关于农药对景观和栖息地变化的影响程度，研究仍然没有定论。值得注意的是，很少有研究明确测试农药是否可以直接负责农业栖息地物种损失的过程。我的目标是开始弄清楚杀虫剂是否在北美鸟类数量的减少中扮演了不成比例的角色，而不仅仅是栖息地向简化景观的改变。通过全面的GIS桌面练习、实地研究和圈养实验，使用了许多常见的农田鸟类(如：草原麻雀和黑鸟，空中食虫燕子和引进的欧洲椋鸟)以及尖端技术（敏感农药残留分析，自动遥测，eDNA元条形码和生物声学分析），我将探索亚致死杀虫剂暴露和影响的多个方面。这项研究将探索支撑稳定鸟类种群和群落的复杂过程，为全球农田鸟类数量下降的根本原因提供新的见解，并找出有助于保护工作的可行解决方案。它还将为学生提供丰富的培训经验，为他们在生态学、生态毒理学和保护生物学领域的各种职业做好准备。

Many migratory and farmland associated bird species are exhibiting precipitous population declines across North America. One of the main putative causes is the role of pesticides affecting birds using agricultural landscapes. Conventional agricultural practices in North America have increased reliance on agrochemicals over the past 35 years to maintain or increase production yields in highly simplified landscapes. Migrating and farmland associated birds can be exposed to toxic insecticides through ingestion of treated seeds or granules, sprayed soils or contaminated prey items and water. Since avian migration is a complex process that requires integration of multisensory information for successful orientation and navigation and rapid refueling at the staging sites, even subtle, insidious perturbations from insecticide exposure could delay a bird's migration, change their route, and reduce their survival and chance to reproduce. However, studies remain inconclusive about the magnitude of pesticide effects relative to landscape and habitat alterations that have co-occurred. Remarkably, few studies have explicitly tested whether pesticides could be directly responsible for processes underpinning species losses in agricultural habitats. My goal is to begin disentangling whether insecticides are playing a disproportionate role in the decline of avifauna in North America relative to habitat alterations toward simplified landscapes alone. Through comprehensive GIS desktop exercises, field studies, and captive experiments using many common farmland bird species (eg. grassland sparrows and blackbirds, aerial insectivorous swallows and introduced European starlings) as well as cutting edge technologies (sensitive pesticide residue analysis, automated telemetry, eDNA metabarcoding and bioacoustic analyses), I will explore the multiple aspects of sublethal insecticide exposures and effects. The research will explore the complex processes that underpin stable bird populations and communities, provide new insight into the root causes of global farmland bird declines, and pinpoint viable solutions that can aid conservation efforts.  It will also create a platform for a rich training experience for students to prepare them for diverse careers in ecology, ecotoxicology and conservation biology fields.