Calhoun Kendall L, Connor Thomas, Gaynor Kaitlyn M, Van Scoyoc Amy, McInturff Alex, Kreling Samantha E S, Brashares Justin S
Department of Environmental, Science, Policy, and Management, University of California Berkeley, 137 Mulford #3114, Berkeley, CA, 94720, USA.
, 210 Wellman Hall, Berkeley, CA, 94720, USA.
Mov Ecol. 2024 Jul 31;12(1):53. doi: 10.1186/s40462-024-00488-4.
Movement plays a key role in allowing animal species to adapt to sudden environmental shifts. Anthropogenic climate and land use change have accelerated the frequency of some of these extreme disturbances, including megafire. These megafires dramatically alter ecosystems and challenge the capacity of several species to adjust to a rapidly changing landscape. Ungulates and their movement behaviors play a central role in the ecosystem functions of fire-prone ecosystems around the world. Previous work has shown behavioral plasticity is an important mechanism underlying whether large ungulates are able to adjust to recent changes in their environments effectively. Ungulates may respond to the immediate effects of megafire by adjusting their movement and behavior, but how these responses persist or change over time following disturbance is poorly understood.
We examined how an ecologically dominant ungulate with strong site fidelity, Columbian black-tailed deer (Odocoileus hemionus columbianus), adjusted its movement and behavior in response to an altered landscape following a megafire. To do so, we collected GPS data from 21 individual female deer over the course of a year to compare changes in home range size over time and used resource selection functions (RSFs) and hidden Markov movement models (HMMs) to assess changes in behavior and habitat selection.
We found compelling evidence of adaptive capacity across individual deer in response to megafire. Deer avoided exposed and severely burned areas that lack forage and could be riskier for predation immediately following megafire, but they later altered these behaviors to select areas that burned at higher severities, potentially to take advantage of enhanced forage.
These results suggest that despite their high site fidelity, deer can navigate altered landscapes to track rapid shifts in encounter risk with predators and resource availability. This successful adjustment of movement and behavior following extreme disturbance could help facilitate resilience at broader ecological scales.
移动在动物物种适应突发环境变化中起着关键作用。人为的气候和土地利用变化加速了其中一些极端干扰的频率，包括特大火灾。这些特大火灾极大地改变了生态系统，并挑战了多个物种适应快速变化景观的能力。有蹄类动物及其移动行为在全球易发生火灾的生态系统的生态系统功能中起着核心作用。先前的研究表明，行为可塑性是大型有蹄类动物能否有效适应其环境近期变化的重要潜在机制。有蹄类动物可能会通过调整其移动和行为来应对特大火灾的直接影响，但人们对这些反应在干扰后如何持续或随时间变化却知之甚少。
我们研究了一种具有强烈地点忠诚度的生态优势有蹄类动物——哥伦比亚黑尾鹿（Odocoileus hemionus columbianus），在特大火灾后如何根据景观变化调整其移动和行为。为此，我们在一年的时间里收集了21只雌性鹿的GPS数据，以比较家域大小随时间的变化，并使用资源选择函数（RSF）和隐马尔可夫移动模型（HMM）来评估行为和栖息地选择的变化。
我们发现了个体鹿对特大火灾具有适应能力的有力证据。鹿在特大火灾后立即避开了缺乏草料且捕食风险更高的暴露和严重烧毁区域，但它们后来改变了这些行为，选择了燃烧程度更高的区域，可能是为了利用增加的草料。
这些结果表明，尽管鹿具有很高的地点忠诚度，但它们能够在变化的景观中导航，以追踪与捕食者相遇风险和资源可用性的快速变化。在极端干扰后成功调整移动和行为有助于在更广泛的生态尺度上促进恢复力。
