Abstract Optimal foraging theory provides a powerful quantitative framework to reveal how foraging constraints and options define the interplay between forager and resource distributions. Although illegal hunting threatens wildlife worldwide, few studies have assessed the impact of poaching on the ability of animals to optimise their use of resources. We assessed how the risk of poaching hinders the ability of common reedbuck (Redunca arundinum), red hartebeest (Alcelaphus buselaphus), and plains zebra (Equus quagga) to maximise their daily intake of digestible energy in a complex mosaic of post-fire vegetation, in a small fenced nature reserve. Optimality models predict that all species can maximise their intake of digestible energy by feeding in young post-fire patches (29–37 days). We show that for all species, probability of finding and selectively using such high-value vegetation patches was higher at greater distance from points where poachers were likely to enter the reserve. For reedbuck, optimal patches were used only if they were >3.4 km from poacher entry-points. Red hartebeest became more likely to occur in optimal vegetation patches as the distance to likely poacher entry points increased. Only zebra maximized their daily intake of digestible energy regardless of the distance to poachers, but still selected areas where poaching was less likely. This study demonstrates how spatial patterns in poacher activities and post-fire vegetation interact to shape herbivore distribution. Understanding how herbivores track and use this post fire green-up of vegetation is important for protected area managers to understand the trade-offs that herbivores make when foraging.

中文翻译：

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偷猎阻碍了三种大型食草动物的最佳火后草料选择

摘要 最优觅食理论提供了一个强大的定量框架来揭示觅食约束和选项如何定义觅食者和资源分布之间的相互作用。尽管非法狩猎威胁着全世界的野生动物，但很少有研究评估偷猎对动物优化资源利用能力的影响。我们评估了偷猎风险如何阻碍普通芦苇 (Redunca arundinum)、红羚 (Alcelaphus buselaphus) 和平原斑马 (Equus quagga) 在火灾后植被的复杂镶嵌中最大限度地提高每日可消化能量的摄入量，在一个小的围栏自然保护区。最优模型预测，所有物种都可以通过在火灾后的年轻斑块（29-37 天）中进食来最大限度地吸收可消化能量。我们表明，对于所有物种，距离偷猎者可能进入保护区的地点越远，发现和有选择地使用这些高价值植被斑块的可能性就越大。对于 reedbuck，仅当它们距离偷猎者入口点 >3.4 公里时才使用最佳补丁。随着与可能的偷猎者进入点的距离增加，红羚羊更有可能出现在最佳植被斑块中。无论与偷猎者的距离如何，只有斑马都能最大限度地提高每日可消化能量的摄入量，但仍会选择偷猎可能性较小的区域。这项研究展示了偷猎者活动和火灾后植被的空间模式如何相互作用以塑造食草动物的分布。