NSF Postdoctoral Fellowship in Biology: Importance of monsoon rains for songbird migration and stopover refueling in the American desert southwest

该行动为2022财年美国国家科学基金会生物学博士后研究奖学金提供资金，扩大生物学中代表性不足群体的参与。该奖学金支持研究员的研究和培训计划，该计划将增加在生物学中代表性不足的群体的参与。每年秋天，数十亿的候鸟穿过索诺兰沙漠、莫哈韦沙漠和奇瓦瓦沙漠，向南迁徙到墨西哥和中美洲的越冬地。这些栖息地与它们在加拿大和阿拉斯加温带北纬地区的夏季繁殖地截然不同。炎热和干旱给鸟类带来了新的挑战，因为它们在继续向南飞行之前，会在西南部的沙漠中停下来补充能量。研究员将调查西南沙漠的季节性季风降雨如何帮助每年秋天经过该地区的鸣禽。每年的季风有可能为鸟类提供更凉爽的温度，更多的地表水，以及丰富的昆虫和种子作为食物。这些资源对于候鸟来说至关重要，因为它们准备不间断地飞越数千公里的干旱土地，然后到达墨西哥中部和南部。目前最好的西南沙漠气候变化模型都表明，季风总降雨量将减少，暴风雨的时间将在未来一个世纪变得更加不稳定。准确了解野生动物目前如何利用季风资源，对于预测这些变化的天气系统如何影响未来的物种至关重要。此外，该奖项将支持研究员开发一个广泛访问的培训研讨会，针对希望获得学术博士后奖学金的不同申请人，该研讨会将在STEM国家多样性会议上提出。本研究的中心目标是确定季风天气事件是否有助于奇瓦瓦沙漠中转站鸣鸟的恢复。该研究员将量化周期性季风降雨对候鸟内源性水分储备的贡献，并确定在干旱陆地中途停留点鸣禽的水分平衡是否限制了整个动物的表现。量化季风降雨对动物水分储备的贡献取决于能够测量复杂生物地球化学系统中氧中子的细微交换。这项研究将使用一种同位素测定法，可以可靠地检测动物组织中的季风降雨脉冲。这种方法对生态学家来说将是一种革命性的工具，而该研究员将是第一个将这种技术应用于该领域的人之一。此外，该研究员将使用标准呼吸测量法测量全动物的代谢性能，并通过使用微创技术分析自由生活鸟类的血浆代谢物来测量加油性能。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2022, Broadening Participation of Groups Underrepresented in Biology. The Fellowship supports a research and training plan for the Fellow that will increase the participation of groups underrepresented in biology. Each fall, billions of migratory birds cross through the Sonoran, Mojave, and Chihuahuan deserts during their southward migration to their wintering grounds in Mexico and Central America. These habitats are drastically different from their summer breeding grounds in temperate northern latitudes of Canada and Alaska. The heat and aridity presents new challenges to birds as they stop to refuel in the desert southwest prior to continuing their journey south. The Fellow will investigate how seasonal monsoon rains in the desert southwest can assist songbirds passing through the region each fall. The annual monsoons have the potential to provide birds with cooler temperatures, greater availability of surface water, and an abundance of insects and seeds for food. These resources are critical for refueling migratory birds as they prepare to fly nonstop over thousands of kilometers of arid lands prior to reaching central and southern Mexico. The best current climate change models for the desert southwest all indicate that total monsoon rainfall will be reduced, and the timing of the storms will become more erratic over the coming century. Understanding precisely how wildlife currently utilize monsoon resources is essential to predict how these changing weather systems can impact species in the future. Additionally, this award will support the Fellow in developing a broadly accessible training workshop directed at diverse applicants wishing to pursue academic postdoctoral fellowships which will be presented at the National Diversity in STEM conference. The central goal of this research is to determine if monsoon weather events assist songbird recovery at stopover sites in the Chihuahuan desert. The Fellow will quantify the contributions that periodic monsoon rains have endogenous water reserves of migrants and determine if whole-animal performance is constrained by water balance in songbirds at arid land stopover sites. Quantifying the contribution of monsoon rainfall to animals’ water reserves depends on being able to measure a nuanced exchange of oxygen neutrons in a complex biogeochemical system. The research will use an isotopic assay which allows for the reliable detection of the monsoon rain pulse in the tissues of animals. This method will be a revolutionary tool for ecologists, and the Fellow will be one of the first to apply this technique in the field. Additionally, the Fellow will measure whole-animal metabolic performance using standard respirometry, and refueling performance by analyzing plasma metabolites using minimally invasive techniques on free-living birds.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.