DISSERTATION RESEARCH: Survival and performance costs of phenotypic responses to predation risk

论文研究：捕食风险表型反应的生存和性能成本

• 批准号: 1701672
• 负责人: Thomas Martin
• 金额: $ 1.87万
• 依托单位: University of Montana
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-15 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1701672&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Survival; performance; costs

This study investigates whether young songbirds that grow faster and leave the nest earlier because of a higher risk of nest predation have lower survival rates after leaving the nest. Predation can be a major source of mortality in wild animal populations. When the risk of predation is variable, prey species are expected to show flexible developmental responses that reduce their risk of being killed by predators. For example, young birds may grow faster and leave the nest earlier when nest predation risk is high. However, flexible developmental responses at early life stages may be physiologically costly and increase mortality at later life stages. By simulating increased predation, the researchers will experimentally determine the effects of variable nest predation on nestling growth rate and timing of fledging for Dark-eyed Juncos. Each bird will be tagged with a radio transmitter to determine their fates after leaving the nest. The study will also address whether activity levels and behaviors of fledglings reduce mortality risks and compensate for physiological costs. Results will provide critical insights on the key factors that control the growth and decline of wild animal populations, and lead to more effective management of these populations. In addition, the project will involve mentoring of both undergraduate and graduate students, and will develop educational materials for high school students. Educational videos for school age children will also be created for a local science education center.This project tests the hypothesis that faster growth of Dark-eyed Juncos in response to nest predation risk compromises mobility and causes increased mortality risk at older life history stages. Researchers will use speakers to broadcast sounds of typical nest predators to increase the perception of nest predation risk by parents and offspring to examine its consequences for mortality after fledging. Preliminary data show that young nestlings in 'high risk' nests leave the nest with shorter wings and are less adept at flying, but it is unclear if these same individuals are predated more often after leaving. Just before the nestlings leave the nest the researchers will attach radio transmitters to aid in tracking. Data will be collected on how often and how far the young birds move around each day after they leave the nest; whether they hide more often in denser vegetation where predators, like hawks, have greater difficulty getting to them; and whether they actually are more likely to die. Results will advance our understanding of carryover effects from growth plasticity on offspring mortality during later life stages.

这项研究调查了是否年轻的鸣禽生长更快，离开巢，因为更高的风险巢捕食后，离开巢的存活率较低。捕食可能是野生动物种群死亡的主要原因。当捕食的风险是可变的，被捕食物种预计将显示灵活的发展反应，减少被捕食者杀死的风险。例如，幼鸟可能生长得更快，在巢捕食风险高的时候更早离开巢。然而，在生命早期阶段灵活的发育反应可能是生理上代价高昂的，并增加生命后期阶段的死亡率。通过模拟增加捕食，研究人员将实验性地确定可变的巢捕食对雏鸟生长速度和黑眼容科斯雏鸟羽翼丰满时间的影响。每只鸟都将被贴上无线电发射器的标签，以确定它们离开巢穴后的命运。该研究还将探讨幼鸟的活动水平和行为是否会降低死亡风险并补偿生理成本。研究结果将为控制野生动物种群增长和下降的关键因素提供重要见解，并导致对这些种群进行更有效的管理。此外，该项目还将涉及对本科生和研究生的辅导，并将为高中生编写教材。该项目还将为当地科学教育中心制作学龄儿童教育视频。该项目测试了黑眼容科斯在应对巢穴捕食风险时的快速增长会影响移动性并导致老年生命史阶段死亡风险增加的假设。研究人员将使用扬声器广播典型的巢穴捕食者的声音，以增加父母和后代对巢穴捕食风险的感知，以研究其对雏鸟死亡率的影响。初步数据显示，“高风险”巢穴中的雏鸟离开巢穴时翅膀较短，不太擅长飞行，但目前还不清楚这些个体离开后是否更经常被捕食。就在雏鸟离巢之前，研究人员会安装无线电发射器来帮助跟踪。这些数据将被收集，包括幼鸟离巢后每天移动的频率和距离;它们是否更经常地隐藏在更密集的植被中，在那里，像鹰这样的捕食者更难接近它们;以及它们是否真的更有可能死亡。研究结果将促进我们的理解结转的影响，从生长可塑性对后代死亡率在以后的生活阶段。