Mammalian spatial and temporal activity patterns can vary depending on foraging behavior or the perception of predation or competition risk among species. These behaviors may in turn be altered by human influences such as defaunation. Herein, we evaluate whether frugivores avoid areas with high visitation rates by potential predators or competitors, and whether this avoidance changes in areas with different degrees of defaunation. We installed 189 cameras under fruit trees in six areas of the Atlantic Forest, Brazil, that differ in the abundance of top predators and large frugivores. Small predators and small frugivores were more frequent at night while large frugivores were more frequent during the day, but small frugivores visited and spent less time at fruiting trees on brighter nights, unlike large predators and large frugivores. Small frugivores also were less frequent in areas with high visitation by large frugivores and more frequent in highly defaunated areas. Our results suggest that the dynamics among mammalian functional groups varied according to diel patterns, potential competitors, and defaunation. We highlight the importance of understanding how species interactions are changing in areas exposed to strong human impacts to mitigate the indirect effects of defaunation.

中文翻译：

---

大小和恐惧的问题：食果动物和捕食者之间的竞争和捕食风险感知

哺乳动物的空间和时间活动模式可能因觅食行为或对物种之间捕食或竞争风险的感知而异。这些行为反过来可能会因动物区系丧失等人类影响而改变。在此，我们评估食果动物是否避开潜在捕食者或竞争者访问率高的区域，以及这种避免在动物区系破坏程度不同的区域是否会发生变化。我们在巴西大西洋森林的六个区域的果树下安装了 189 个摄像头，这些区域的顶级掠食者和大型食果动物的数量不同。小型食肉动物和小型食果动物在夜间更频繁，而大型食果动物在白天更频繁，但与大型食肉动物和大型食果动物不同，小型食肉动物在明亮的夜晚访问并在果树上花费的时间更少。在大型食果动物频繁访问的地区，小型食果动物的频率也较低，而在高度动物化的地区则更为频繁。我们的结果表明，哺乳动物功能群之间的动态因生存模式、潜在竞争者和动物区系丧失而异。我们强调了解物种相互作用如何在受到强烈人类影响的地区发生变化以减轻动物区系丧失的间接影响的重要性。