Are human-altered landscapes reshaping carnivore niche spaces in the trans-Himalaya?

Understanding carnivore interactions under growing human pressures is crucial for conservation. We examined spatial and temporal niche structuring among snow leopards (Panthera uncia), Himalayan wolves (Canis lupus chanco), and red foxes (Vulpes vulpes), while also incorporating free-ranging dogs (Canis lupus familiaris) as a human-subsidized mesopredator whose presence reflects and amplifies anthropogenic pressures. Using camera-trap data from the trans-Himalayan landscape of Spiti, we applied multi-species occupancy, spatial co-occurrence, and diel activity analyses to study how human influence and interspecific interactions shape carnivore coexistence. Spatial analyses revealed positive associations between red fox occupancy and other carnivores, influenced by elevation, prey availability, and distance to human settlements, likely reflecting facilitation via scavenging opportunities. In contrast, interactions among dogs, wolves, and snow leopards were more variable, with both positive and negative spatial associations depending on environmental covariates. Temporal partitioning was a key strategy for both red foxes and snow leopards to avoid dogs; however, foxes showed no significant diel shifts when co-occurring with snow leopards, indicating limited temporal avoidance. Snow leopards increased activity but delayed peaks with a greater human footprint, likely exploiting livestock or prey drawn to such areas. Red foxes, by contrast, delayed peaks but maintained activity, and dogs maintained stable activity patterns regardless of human footprint. Together, these results demonstrate that carnivores actively structure their niches in response to both human pressures and interspecific interactions, facilitating coexistence despite overlap in resource use. Free-ranging dogs represent an emerging conservation concern in the region, underscoring the need for their management and reducing human disturbance in critical areas. Integrating insights from multiple niche axes can inform more holistic and effective strategies to promote carnivore coexistence in human-influenced mountain landscapes.

在人类活动压力持续加剧的背景下，理解食肉动物间的相互作用对于生物多样性保护至关重要。本研究针对雪豹（Panthera uncia）、喜马拉雅狼（Canis lupus chanco）与赤狐（Vulpes vulpes）的时空生态位分化模式展开调查，同时将散养犬（Canis lupus familiaris）纳入研究范畴——这类依赖人类补给的中型捕食者，其种群分布既是人为活动压力的直观体现，也会进一步放大这类压力。本研究依托跨喜马拉雅地区斯皮蒂流域的相机陷阱（camera-trap）监测数据，采用多物种占用模型（multi-species occupancy）、空间共现分析（spatial co-occurrence）与昼夜活动节律分析（diel activity analyses）方法，探究人类活动影响与种间相互作用如何塑造食肉动物的共存模式。空间分析结果显示，赤狐的栖息地占用率与其他食肉动物呈正相关关系，该模式受海拔、猎物可获取性以及距人类定居点距离的共同调控，这大概率反映了赤狐通过食腐机会获得的生存促进效应。与之形成对比的是，散养犬、狼与雪豹之间的种间相互作用模式更为多变，二者的空间共现关系存在正负两种情况，具体取决于环境协变量的影响。时间生态位分化是赤狐与雪豹规避散养犬的核心策略；但当赤狐与雪豹同域共存时，赤狐并未出现显著的昼夜活动节律偏移，这表明二者之间的时间规避效应十分有限。当人类活动影响强度升高时，雪豹的整体活动量有所提升，但活动峰值出现时间延后，这可能是因为它们会利用被吸引至此类区域的家畜或野生猎物。与之相反，赤狐同样会延后活动峰值，但整体活动量保持稳定；而散养犬的活动模式则不受人类活动影响强度的调控，始终保持稳定。综合来看，上述研究结果表明，食肉动物会主动调整自身生态位以应对人类活动压力与种间相互作用的双重影响，即便存在资源利用重叠，仍能通过这种调整实现种群共存。散养犬已成为该区域新兴的生物多样性保护关注点，这凸显了对其开展种群管理、并在关键生境中降低人类干扰的必要性。整合多维度生态位的研究结论，可为在受人类活动影响的山地景观中制定更具整体性与实效性的食肉动物共存保护策略提供科学依据。