Plant Ecology and Nature Conservation, University of Potsdam, 14469 Potsdam, Germany.
Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, 10315 Berlin, Germany.
Proc Natl Acad Sci U S A. 2022 Aug 16;119(33):e2203663119. doi: 10.1073/pnas.2203663119. Epub 2022 Aug 8.
Animals that depend on ephemeral, patchily distributed prey often use public information to locate resource patches. The use of public information can lead to the aggregation of foragers at prey patches, a mechanism known as local enhancement. However, when ephemeral resources are distributed over large areas, foragers may also need to increase search efficiency, and thus apply social strategies when sampling the landscape. While sensory networks of visually oriented animals have already been confirmed, we lack an understanding of how acoustic eavesdropping adds to the formation of sensory networks. Here we radio-tracked a total of 81 aerial-hawking bats at very high spatiotemporal resolution during five sessions over 3 y, recording up to 19 individuals simultaneously. Analyses of interactive flight behavior provide conclusive evidence that bats form temporary mobile sensory networks by adjusting their movements to neighboring conspecifics while probing the airspace for prey. Complementary agent-based simulations confirmed that the observed movement patterns can lead to the formation of mobile sensory networks, and that bats located prey faster when networking than when relying only on local enhancement or searching solitarily. However, the benefit of networking diminished with decreasing group size. The combination of empirical analyses and simulations elucidates how animal groups use acoustic information to efficiently locate unpredictable and ephemeral food patches. Our results highlight that declining local populations of social foragers may thus suffer from Allee effects that increase the risk of collapses under global change scenarios, like insect decline and habitat degradation.
依赖短暂且分散分布的猎物的动物通常会利用公共信息来定位资源斑块。利用公共信息可以导致觅食者在猎物斑块处聚集，这一机制被称为局部增强。然而，当短暂的资源分布在较大的区域时，觅食者可能还需要提高搜索效率，因此在对景观进行采样时会采用社会策略。虽然已经证实了视觉导向动物的感官网络的存在，但我们还不了解声学偷听如何增加感官网络的形成。在这里，我们在 3 年的 5 次会议期间，以非常高的时空分辨率对总共 81 只空中捕食蝙蝠进行了无线电跟踪，同时最多记录了 19 只个体。对互动飞行行为的分析提供了确凿的证据，表明蝙蝠通过调整它们的运动来与相邻的同种个体相互作用，同时在空气中探测猎物，从而形成临时的移动感官网络。补充的基于代理的模拟证实，观察到的运动模式可以导致移动感官网络的形成，并且当网络比仅依靠局部增强或单独搜索时，蝙蝠可以更快地定位猎物。然而，网络的好处随着群体规模的减小而减少。实证分析和模拟的结合阐明了动物群体如何利用声学信息来有效地定位不可预测和短暂的食物斑块。我们的研究结果表明，社交觅食者的局部种群数量下降可能会导致阿利效应，即在昆虫减少和栖息地退化等全球变化情景下，增加崩溃的风险。
