LTREB Renewal: Mechanisms driving facultative switching in a partially migratory large-herbivore population

迁徙物种对生态系统功能至关重要，因为它们可以通过迁徙获得更高的丰度，从而经常驱动生态过程。然而，由于人类的干扰、栖息地的丧失和环境的变化，世界范围内的迁徙物种也在减少。特别是，大型有蹄类动物（如鹿、麋鹿）在生态和经济上都很重要（如狩猎），但它们的迁徙也在减少。了解迁徙有蹄类动物数量减少的原因对它们的保护和管理具有重要意义。然而，在不同的迁徙物种中，在同一个种群中，通常有迁徙的个体和不迁徙的个体。先前的研究还表明，个体有蹄类动物的迁徙行为是灵活的，它们可以根据环境的变化来决定是否迁徙，或者迁徙到哪里。本研究将利用一项对北美西部山区景观中迁徙麋鹿长达19年的长期研究，以了解麋鹿迁徙决策的原因，以及迁徙行为变化对麋鹿管理的影响。该研究将对北美西部大量具有重要经济意义的迁徙有蹄类物种（如鹿和麋鹿）的种群和栖息地管理产生广泛的影响。这项研究将延长我们对阿尔伯塔省班夫国家公园边界部分迁徙麋鹿种群的19年长期人口统计研究，以解决驱动部分迁徙的机制。本研究的核心数据是了解400多只已知年龄的雌性麋鹿的人口统计、繁殖率和幼崽存活率，并结合全球定位系统（GPS）项圈对它们迁徙行为的空间分析。我们将测试麋鹿是否以与内在因素（如年龄、身体状况）、外在因素（如气候）或密度依赖机制一致的方式在迁徙策略之间切换。通过监测年龄和繁殖史等内在因素，以及饲料和捕食风险的外在变化，我们将在竞争和相互作用的假设中进行测试，以了解为什么长寿哺乳动物在面对环境变化时在迁移策略之间切换。然后，我们将开发一个灵活的贝叶斯综合种群模型来测试迁移切换对种群动态的影响。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。

Migratory species are crucial to ecosystem function because by migrating they can attain higher abundance, and thus often drive ecological processes. Yet migratory species are also declining worldwide because of human disturbance, habitat loss, and environmental variability. In particular, large ungulates (e.g., deer, elk) are both ecologically and economically important (e.g., hunting), and yet their migrations are also in decline. Understanding the causes of declining migratory ungulates has important implications for their conservation and management. However, across migratory species, there are usually individuals who migrate and individuals who do not migrate within a single population. Previous research also showed individual ungulates can be flexible in their migratory behavior, deciding whether to migrate or not, or where to migrate, based on changes in their environment. This research will take advantage of a 19-year, long-term study of migratory elk in a western North American montane landscape to understand both the causes of migratory decision-making in elk, as well as the population consequences of changes in migratory behavior to the management of elk. This research will have broad implications for population and habitat management for a wide range of economically-important migratory ungulate species such as deer and elk across western North America. This research will extend our long-term 19-year demographic study of a partially migratory elk population on the border of Banff National Park, Alberta, to address the mechanisms driving partial migration. The core data for this research is understanding the demography of over 400 individually marked female elk of known ages, their reproductive rates, and juvenile survival, combined with spatial analyses of their migratory behavior measured by Global Positioning System (GPS) collars. We will test whether elk switch between migratory strategies in a manner consistent with intrinsic factors (e.g. age, body condition), extrinsic factors (e.g, climate), or density-dependent mechanisms. By monitoring intrinsic factors such as age and reproductive history, as well as extrinsic variation in forage and predation risk, we will test amongst competing and interacting hypotheses to understand why a long-lived mammal switches between migratory strategies in the face of environmental change. We will then develop a flexible Bayesian integrated population model to test the consequences of migratory switching on population dynamics. This model will be generalizable to other partially migratory speciesThis 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.