Data from: Parasite and predator risk assessment: nuanced use of olfactory cues

Foraging herbivores face twin threats of predation and parasite infection, but the risk of predation has received much more attention. We evaluated, experimentally, the role of olfactory cues in predator and parasite risk assessment on the foraging behaviour of a population of marked, free-ranging, red-necked wallabies (Macropus rufogriseus). The wallabies adjusted their behaviour according to these olfactory cues. They foraged less, were more vigilant and spent less time at feeders placed in the vicinity of faeces from dogs that had consumed wallaby or kangaroo meat compared with that of dogs feeding on sheep, rabbit or possum meat. Wallabies also showed a species-specific faecal aversion by consuming less food from feeders contaminated with wallaby faeces compared with sympatric kangaroo faeces, whose gastrointestinal parasite fauna differs from that of the wallabies. Combining both parasite and predation cues in a single field experiment revealed that these risks had an additive effect, rather than the wallabies compromising their response to one risk at the expense of the other.

觅食性植食动物同时面临捕食与寄生虫感染的双重威胁，但学界对捕食风险的研究关注度远高于后者。本研究通过野外实验，评估了嗅觉线索（olfactory cues）在捕食与寄生虫风险评估过程中，对标记个体自由活动的野生红颈袋鼠（Macropus rufogriseus）种群觅食行为的调控作用。该红颈袋鼠种群会依据此类嗅觉线索调整自身行为：相较于饲喂绵羊、兔或负鼠肉类的犬只粪便周边的喂食器，当喂食器位于食用过红颈袋鼠或其他袋鼠类肉类的犬只粪便附近时，红颈袋鼠的觅食频次更低、警戒行为更为频繁，且在喂食器处的停留时长更短。此外，红颈袋鼠还表现出物种特异性的粪便规避行为：相较于同域分布且胃肠道寄生虫区系与红颈袋鼠存在差异的袋鼠粪便污染的喂食器，红颈袋鼠在被自身粪便污染的喂食器处取食的食物量更少。本研究在同一场野外实验中同时结合寄生虫与捕食风险线索，结果表明两类风险对红颈袋鼠的行为调控存在加和效应，而非红颈袋鼠会以牺牲对其中一种风险的响应为代价来应对另一种风险。