Randler Christoph, Kalb Jochen
Eberhard Karls University of Tuebingen, Department of Biology, Auf der Morgenstelle 24, D-72076, Tuebingen, Germany.
Eberhard Karls University of Tuebingen, Department of Biology, Auf der Morgenstelle 24, D-72076, Tuebingen, Germany.
Behav Processes. 2020 Oct;179:104214. doi: 10.1016/j.beproc.2020.104214. Epub 2020 Aug 6.
Animals trade-off predation risk against feeding opportunities and prey species may use signals or cues of predators to assess predation risk. We analyzed the mesopredators pine and stone marten (Martes martes, M. foina) and nocturnal and diurnal rodents (Glis glis, Apodemus spp., Sciurus vulgaris). The non-experimental approach used camera traps at feeders which were visited by both, predator and prey. As prey species can eavesdrop on predator signals/cues, there should show some avoidance behavior. The study was conducted on a small mountain in Germany, largely covered by wood, between 29.6.2018 and 5.10.2018. Camera traps were placed 0.6 m near a feeder. Food was replenished regularly to provide a continuous food supply. 34 camera traps provided data for an analysis; total trap nights were 513 (12,312 h). Martens detected the food sources first in 10 instances, and prey species Apodemus/G. glis in 24 instances. G. glis seemed to generally avoid places where martens were feeding while Apodemus and Sciurus did not. The visitations of G. glis depended on whether martens were the first visitors and it significantly avoided such places. Similarly, Apodemus appeared less often at a feeder when martens have been present as a first visitor. The time interval to resume feeding to a monitored feeder after a marten visit was significantly longer compared to a control in G. glis, but not in Apodemus and S. vulgaris. The study shows different responses, with the weakest in the diurnal rodent, and the highest in G. glis. Thus, if a food resource was known by prey species before a predator occurred, the trade-off was shifted towards feeding, but when the predators detect the food source first, the trade-off was shifted to predator avoidance.
动物会在捕食风险与觅食机会之间进行权衡，猎物物种可能会利用捕食者的信号或线索来评估捕食风险。我们分析了中型捕食者松貂和石貂（松貂、石貂）以及夜行性和昼行性啮齿动物（大睡鼠、姬鼠属、松鼠）。我们采用非实验方法，在捕食者和猎物都会光顾的喂食器处设置了相机陷阱。由于猎物物种能够窃听捕食者的信号/线索，所以应该会表现出一些回避行为。该研究于德国一座大部分被树林覆盖的小山上进行，时间为2018年6月29日至2018年10月5日。相机陷阱放置在离喂食器0.6米的地方。食物定期补充以提供持续的食物供应。34个相机陷阱提供了用于分析的数据；总陷阱夜数为513（12312小时）。貂在10次情况下首先发现了食物来源，猎物物种姬鼠/大睡鼠在24次情况下发现了食物来源。大睡鼠似乎通常会避开貂进食的地方，而姬鼠和松鼠则不会。大睡鼠的光顾取决于貂是否是第一个访客，并且它会显著避开这些地方。同样，当貂作为第一个访客出现时，姬鼠出现在喂食器处的频率较低。与对照组相比，大睡鼠在貂访问后恢复到被监测喂食器进食的时间间隔显著更长，但姬鼠和松鼠则没有。该研究显示了不同的反应，昼行性啮齿动物的反应最弱，大睡鼠的反应最强。因此，如果猎物物种在捕食者出现之前就知道有食物资源，权衡就会转向进食，但当捕食者首先发现食物来源时，权衡就会转向躲避捕食者。
