Center for Integrated Spatial Research, Environmental Studies Department, University of California, Santa Cruz, CA 95064
Center for Integrated Spatial Research, Environmental Studies Department, University of California, Santa Cruz, CA 95064.
Proc Natl Acad Sci U S A. 2021 Feb 2;118(5). doi: 10.1073/pnas.2004592118.
Energetic demands and fear of predators are considered primary factors shaping animal behavior, and both are likely drivers of movement decisions that ultimately determine the spatial ecology of wildlife. Yet energetic constraints on movement imposed by the physical landscape have only been considered separately from those imposed by risk avoidance, limiting our understanding of how short-term movement decisions scale up to affect long-term space use. Here, we integrate the costs of both physical terrain and predation risk into a common currency, energy, and then quantify their effects on the short-term movement and long-term spatial ecology of a large carnivore living in a human-dominated landscape. Using high-resolution GPS and accelerometer data from collared pumas (), we calculated the short-term (i.e., 5-min) energetic costs of navigating both rugged physical terrain and a landscape of risk from humans (major sources of both mortality and fear for our study population). Both the physical and risk landscapes affected puma short-term movement costs, with risk having a relatively greater impact by inducing high-energy but low-efficiency movement behavior. The cumulative effects of short-term movement costs led to reductions of 29% to 68% in daily travel distances and total home range area. For male pumas, long-term patterns of space use were predominantly driven by the energetic costs of human-induced risk. This work demonstrates that, along with physical terrain, predation risk plays a primary role in shaping an animal's "energy landscape" and suggests that fear of humans may be a major factor affecting wildlife movements worldwide.
能量需求和对捕食者的恐惧被认为是塑造动物行为的主要因素，这两者都可能是运动决策的驱动因素，而这些决策最终决定了野生动物的空间生态。然而，运动受到物理景观的能量限制，与避免风险所施加的限制分开考虑，这限制了我们对短期运动决策如何扩展以影响长期空间利用的理解。在这里，我们将物理地形和捕食风险的成本整合到一个共同的货币中，即能量，然后量化它们对生活在以人类为主导的景观中的大型食肉动物的短期运动和长期空间生态的影响。我们使用佩戴项圈的美洲狮（）的高分辨率 GPS 和加速度计数据，计算了在崎岖不平的物理地形和人类带来的风险景观（我们研究种群的死亡和恐惧的主要来源）中导航的短期（即 5 分钟）能量成本。物理和风险景观都影响了美洲狮的短期运动成本，风险通过诱导高能量但低效率的运动行为产生了相对更大的影响。短期运动成本的累积效应导致每日旅行距离和总家域面积减少了 29%至 68%。对于雄性美洲狮，空间利用的长期模式主要由人类引起的风险的能量成本驱动。这项工作表明，与物理地形一样，捕食风险在塑造动物的“能量景观”方面起着主要作用，并表明对人类的恐惧可能是影响全球野生动物运动的一个主要因素。
