Center for Integrated Spatial Research, Environmental Studies Department, University of California, Santa Cruz, CA, USA.
Conservation Science Partners, Truckee, CA, USA.
J Anim Ecol. 2022 Jan;91(1):182-195. doi: 10.1111/1365-2656.13613. Epub 2021 Oct 29.
When navigating heterogeneous landscapes, large carnivores must balance trade-offs between multiple goals, including minimizing energetic expenditure, maintaining access to hunting opportunities and avoiding potential risk from humans. The relative importance of these goals in driving carnivore movement likely changes across temporal scales, but our understanding of these dynamics remains limited. Here we quantified how drivers of movement and habitat selection changed with temporal grain for two large carnivore species living in human-dominated landscapes, providing insights into commonalities in carnivore movement strategies across regions. We used high-resolution GPS collar data and integrated step selection analyses to model movement and habitat selection for African lions Panthera leo in Laikipia, Kenya and pumas Puma concolor in the Santa Cruz Mountains of California across eight temporal grains, ranging from 5 min to 12 hr. Analyses considered landscape covariates that are related to energetics, resource acquisition and anthropogenic risk. For both species, topographic slope, which strongly influences energetic expenditure, drove habitat selection and movement patterns over fine temporal grains but was less important at longer temporal grains. In contrast, avoiding anthropogenic risk during the day, when risk was highest, was consistently important across grains, but the degree to which carnivores relaxed this avoidance at night was strongest for longer term movements. Lions and pumas modified their movement behaviour differently in response to anthropogenic features: lions sped up while near humans at fine temporal grains, while pumas slowed down in more developed areas at coarse temporal grains. Finally, pumas experienced a trade-off between energetically efficient movement and avoiding anthropogenic risk. Temporal grain is an important methodological consideration in habitat selection analyses, as drivers of both movement and habitat selection changed across temporal grain. Additionally, grain-dependent patterns can reflect meaningful behavioural processes, including how fitness-relevant goals influence behaviour over different periods of time. In applying multi-scale analysis to fine-resolution data, we showed that two large carnivore species in very different human-dominated landscapes balanced competing energetic and safety demands in largely similar ways. These commonalities suggest general strategies of landscape use across large carnivore species.
当在异质景观中导航时，大型食肉动物必须在多个目标之间权衡取舍，包括最小化能量消耗、保持获得狩猎机会的机会并避免来自人类的潜在风险。这些目标在推动食肉动物运动中的相对重要性可能随时间尺度而变化，但我们对这些动态的理解仍然有限。在这里，我们量化了两种生活在人类主导景观中的大型食肉动物的运动和栖息地选择如何随时间粒度而变化，为了解跨区域的食肉动物运动策略的共性提供了见解。我们使用高分辨率 GPS 项圈数据并结合分步选择分析，在肯尼亚莱基皮亚的非洲狮（ Panthera leo ）和加利福尼亚州圣克鲁斯山脉的美洲狮（ Puma concolor ）跨越八个时间粒度（从 5 分钟到 12 小时）来模拟运动和栖息地选择。分析考虑了与能量学、资源获取和人为风险有关的景观协变量。对于这两个物种，强烈影响能量消耗的地形坡度在精细的时间粒度上驱动着栖息地选择和运动模式，但在较长的时间粒度上则不太重要。相比之下，在白天（风险最高时）避免人为风险一直是很重要的，但在较长的时间段内，食肉动物放松这种回避的程度最强。狮子和美洲狮以不同的方式响应人为特征来改变它们的运动行为：狮子在精细的时间粒度附近靠近人类时会加速，而美洲狮在较粗的时间粒度上在更发达的地区会减速。最后，美洲狮在节能运动和避免人为风险之间进行了权衡。时间粒度是栖息地选择分析中的一个重要方法考虑因素，因为运动和栖息地选择的驱动因素随时间粒度而变化。此外，依赖于粒度的模式可以反映有意义的行为过程，包括与适应性相关的目标如何在不同的时间段内影响行为。通过将多尺度分析应用于精细分辨率的数据，我们表明，在非常不同的人类主导景观中两种大型食肉动物以大致相似的方式平衡了相互竞争的能量和安全需求。这些共性表明了大型食肉动物物种在景观利用方面的一般策略。
