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.

这项研究调查了离开巢穴后，由于巢捕食的风险较高，生长速度较高的年轻鸣禽是否会降低巢穴的生存率。捕食可能是野生动物种群死亡率的主要来源。当捕食风险变化时，预计猎物将显示出柔性的发育反应，以降低其被捕食者杀死的风险。例如，当巢捕食风险很高时，幼鸟可能会更快地生长，并更早地离开巢。但是，早期生命阶段的灵活发展反应在生理上可能是昂贵的，并且在以后的生活阶段增加了死亡率。通过模拟捕食的增加，研究人员将在实验上确定可变巢捕食对巢穴生长速率和雏鸟的时间的影响。每只鸟将用无线电发射机标记，以确定离开巢穴后的命运。这项研究还将解决刚果蝇的活动水平和行为是否降低死亡率风险并弥补生理成本。结果将为控制野生动物种群的生长和下降的关键因素提供关键见解，并导致对这些人群的更有效管理。此外，该项目将涉及指导本科生和研究生，并将为高中生开发教育材料。还将针对当地科学教育中心创建针对学龄儿童的教育视频。该项目测试了以下假设：响应巢穴捕食风险的黑眼眼睛的生长更快，会损害流动性，并在较旧的人生历史阶段引起死亡风险增加。研究人员将使用扬声器来广播典型的巢式捕食者的声音，以增加父母和后代对巢捕食风险的看法，以检查其逃离后死亡率的后果。初步数据表明，“高风险”巢中的年轻雏鸟以较短的翅膀离开巢，并且不太熟练飞行，但是目前尚不清楚这些同一个人是否在离开后的经常频繁。 Just before the nestlings leave the nest the researchers will attach radio transmitters to aid in tracking.数据将收集有关幼鸟离开巢穴后每天四处移动的频率和多远的数据；它们是否经常隐藏在较密集的植被中，捕食者（如鹰派）难以吸引他们。以及它们是否实际上更有可能死亡。结果将使我们对生长可塑性对后代死亡率的结转影响的理解。