abr_data from Frightened of giants: fear responses to elephants approach that of predators

Animals are faced with a variety of dangers or threats, which are increasing in frequency with ongoing environmental change. While our understanding of fearfulness of such dangers is growing in the context of predation and parasitism risk, the extent to which non-trophic, interspecific dangers elicit fear in animals remains less appreciated. We provide an experimental test for fear responses of savannah ungulates to a dominant and aggressive megaherbivore, the African bush elephant (Loxodonta africana), and contrast responses to an apex predator known to elicit fear in this system. Using an automated behavioural response system, we contrast vigilance and run responses of ungulates to elephant, leopard (Panthera pardus), and control (red-chested cuckoo Cuculus solitarius) vocalizations. Overall, we find that ungulates responded to elephant calls, both in terms of an increase in run and vigilance responses relative to controls. The magnitude of most behavioural responses (four of six considered) to elephant vocalizations were not significantly different than responses to leopards. These results suggest that megaherbivores can elicit strong non-trophic fear responses by ungulates and call to broaden frameworks on fear to consider dominant species, such as megaherbivores, as key modifiers of fear-induced interactions.

野生动物正面临着随环境持续变化而频率不断升高的各类危险与威胁。尽管我们在捕食和寄生风险背景下对动物的恐惧行为认知逐渐加深，但非营养级种间威胁在多大程度上能引发动物的恐惧反应，仍未得到足够重视。本研究针对稀树草原有蹄类动物对一种优势且具有攻击性的巨型草食动物——非洲丛林象（Loxodonta africana）的恐惧反应开展了实验测试，并将其与该生态系统中已知会引发恐惧的顶级捕食者的刺激反应进行对比。研究借助自动化行为响应系统，对比了有蹄类动物对大象、豹（Panthera pardus）以及对照刺激（红胸凤头鹃Cuculus solitarius鸣叫声）的警戒和奔跑反应。整体而言，相较于对照组，有蹄类动物对大象鸣叫声的奔跑和警戒反应均有所提升。大象鸣叫声引发的多数行为反应（所考量的6项反应中的4项），其强度与豹所引发的反应无显著差异。上述结果表明，巨型草食动物能够引发有蹄类动物强烈的非营养级恐惧反应，这呼吁学界拓宽恐惧相关研究框架，将巨型草食动物这类优势物种视为恐惧介导种间互作的关键调控者。