Department of Ecology, Evolution, and & Behavior, University of Minnesota, St. Paul, MN, USA.
Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota, St. Paul, MN, USA.
Ecol Lett. 2017 Nov;20(11):1364-1373. doi: 10.1111/ele.12832. Epub 2017 Sep 12.
Ambiguous empirical support for 'landscapes of fear' in natural systems may stem from failure to consider dynamic temporal changes in predation risk. The lunar cycle dramatically alters night-time visibility, with low luminosity increasing hunting success of African lions. We used camera-trap data from Serengeti National Park to examine nocturnal anti-predator behaviours of four herbivore species. Interactions between predictable fluctuations in night-time luminosity and the underlying risk-resource landscape shaped herbivore distribution, herding propensity and the incidence of 'relaxed' behaviours. Buffalo responded least to temporal risk cues and minimised risk primarily through spatial redistribution. Gazelle and zebra made decisions based on current light levels and lunar phase, and wildebeest responded to lunar phase alone. These three species avoided areas where likelihood of encountering lions was high and changed their behaviours in risky areas to minimise predation threat. These patterns support the hypothesis that fear landscapes vary heterogeneously in both space and time.
自然系统中“恐惧景观”的经验证据存在歧义,可能源于未能考虑捕食风险的动态时间变化。月相周期极大地改变了夜间的可见度,低光照度增加了非洲狮的狩猎成功率。我们利用塞伦盖蒂国家公园的摄像机陷阱数据,研究了四种食草动物的夜间抗捕食者行为。夜间光照度的可预测波动与潜在的风险资源景观之间的相互作用,塑造了食草动物的分布、群集倾向和“放松”行为的发生率。水牛对时间风险线索的反应最小,主要通过空间重新分布来最小化风险。瞪羚和斑马根据当前的光照水平和月相做出决策,而角马则仅对月相做出反应。这三个物种避开了狮子出没可能性高的区域,并在危险区域改变行为以最小化捕食威胁。这些模式支持了这样一种假设,即恐惧景观在空间和时间上都是不均匀变化的。