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

迁徙物种对生态系统的功能至关重要，因为通过迁徙，它们可以获得更高的丰度，从而经常推动生态过程。然而，由于人类干扰、栖息地丧失和环境变化，迁徙物种在全球范围内也在减少。特别是，大型有蹄类动物(例如鹿、麋鹿)在生态和经济上都具有重要意义(例如狩猎)，但它们的迁徙也在减少。了解迁徙有蹄类衰退的原因对它们的保护和管理具有重要意义。然而，在迁徙物种中，通常有迁徙的个体和不在单一种群内迁徙的个体。之前的研究还表明，个别有蹄类动物可以灵活地迁徙行为，根据环境的变化决定是否迁徙或迁徙到哪里。这项研究将利用对北美西部山地景观中迁徙的麋鹿长达19年的长期研究，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种群后果。这项研究将对北美西部广泛的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。这项研究将扩展我们对艾伯塔省班夫国家公园边境部分迁徙的麋鹿种群进行了长达19年的人口统计学研究，以解决驱动部分迁徙的机制。这项研究的核心数据是了解400多只已知年龄的单独标记的雌性麋鹿的人口学数据、它们的繁殖率和幼崽存活率，并结合全球定位系统(GPS)项圈测量的它们迁徙行为的空间分析。我们将测试麋鹿在迁徙策略之间的转换是否与内在因素(如年龄、身体状况)、外在因素(如气候)或密度依赖机制一致。通过监测年龄和生殖史等内在因素，以及饲料和捕食风险的外部变异，我们将在相互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会在迁徙策略之间切换。然后，我们将开发一个灵活的贝叶斯综合人口模型，以测试迁徙转变对人口动态的影响。这一模式将推广到其他部分迁徙物种。这一裁决反映了NSF的法定使命，并通过使用基金会的智力优势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.