Effects of human-induced prey depletion on large carnivores in protected areas: Lessons from modeling tiger populations in stylized spatial scenarios
Effects of human-induced prey depletion on large carnivores in protected areas: Lessons from modeling tiger populations in stylized spatial scenarios
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DOI：
10.1002/ece3.5632
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发表时间：
2019-09-08
影响因子：
2.6
通讯作者：
Grimm, Volker
中科院分区：
文献类型：
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作者：
Carter, Neil H.;Levin, Simon A.;Grimm, Volker
猎物的减少是全球大型食肉动物物种保护面临的主要威胁。然而，在与政策相关的保护区尺度上，我们对猎物枯竭的空间分布如何影响食肉动物的空间利用和种群持久性知之甚少。我们开发了一个空间明确的、基于主体的模型来研究不同的人类引起的猎物消耗实验对孤立保护区内全球濒危老虎（Panthera tigris）的影响——这种情况在老虎的整个活动范围内普遍存在。具体来说，我们进行了120个实验，这些实验在一个程规化的（圆形）景观（1000公里）和尼泊尔的奇旺国家公园（1239公里）中改变了猎物消耗的空间范围和强度。随着时间的推移，创造更多空间同质猎物分布的实验（即每个细胞的猎物较少，但在更大的区域）导致了更大的老虎领地和更小的种群规模。与直觉相反的是，我们发现在奇旺国家公园边缘的猎物消耗，虽然总体上减少了老虎的数量，但也减少了这些地区的雌性竞争，导致雌性饥饿率降低。总体而言，我们的研究结果表明，各种人类活动（如自然资源利用模式、城市增长和基础设施发展或保护空间区划）造成的猎物密度空间分布的细微差异可能会对食肉动物种群产生意想不到的有害影响。我们的模型是一个有用的规划工具，因为它包含了动物行为生态学、资源空间分布以及这些资源变化的驱动因素（如人类活动）的信息。
Prey depletion is a major threat to the conservation of large carnivore species globally. However, at the policy-relevant scale of protected areas, we know little about how the spatial distribution of prey depletion affects carnivore space use and population persistence. We developed a spatially explicit, agent-based model to investigate the effects of different human-induced prey depletion experiments on the globally endangered tiger (Panthera tigris) in isolated protected areas-a situation that prevails throughout the tiger's range. Specifically, we generated 120 experiments that varied the spatial extent and intensity of prey depletion across a stylized (circle) landscape (1,000 km(2)) and Nepal's Chitwan National Park (1,239 km(2)). Experiments that created more spatially homogenous prey distributions (i.e., less prey removed per cell but over larger areas) resulted in larger tiger territories and smaller population sizes over time. Counterintuitively, we found that depleting prey along the edge of Chitwan National Park, while decreasing tiger numbers overall, also decreased female competition for those areas, leading to lower rates of female starvation. Overall our results suggest that subtle differences in the spatial distributions of prey densities created by various human activities, such as natural resource-use patterns, urban growth and infrastructure development, or conservation spatial zoning might have unintended, detrimental effects on carnivore populations. Our model is a useful planning tool as it incorporates information on animal behavioral ecology, resource spatial distribution, and the drivers of change to those resources, such as human activities.