Predator specific responses and emergent multi-predator effects on oviposition site choice in gray treefrogs, Hyla chrysoscelis

Predators affect prey through both consumptive and non-consumptive effects, and prey typically face threats from multiple simultaneous predators. While different predators have a variety of non-consumptive effects on prey, little is known regarding effects of simultaneous multiple predators on demographic habitat selection. Demographic habitat selection is unique among non-consumptive effects, especially in discrete habitat patches; decisions directly affect both distribution and abundance of species across habitat patches, rather than simply abundance and performance within patches. Our goal was to determine strength of avoidance responses to multiple species/species combinations of predatory fish, and responses to predator richness. We assessed responses of ovipositing gray treefrogs (Hyla chrysoscelis) to three predatory fish species and substitutive combination of species. In single-species treatments, treefrogs avoided only one species, Notemigonus crysoleucas. All two-species comb...捕食者可通过消耗性效应（consumptive effects）与非消耗性效应（non-consumptive effects）对猎物产生影响，而猎物通常会同时面临多种捕食者的威胁。尽管不同捕食者对猎物存在多样的非消耗性效应，但目前对多种捕食者同时存在时对种群动态生境选择（demographic habitat selection）的影响仍知之甚少。种群动态生境选择在各类非消耗性效应中具有独特性，尤其是在离散生境斑块（discrete habitat patches）系统中；猎物的生境选择决策会直接影响物种在不同生境斑块间的分布与种群多度，而非仅局限于斑块内部的种群多度与个体表现。本研究旨在明确猎物对多种鱼类捕食者及其物种组合的躲避响应强度，以及对捕食者丰富度（predator richness）的响应模式。我们以正在产卵的灰树蛙（Hyla chrysoscelis）为研究对象，评估其对3种鱼类捕食者及其物种替代组合的行为响应。在单物种捕食者处理组中，灰树蛙仅会躲避一种鱼类——新月突颌脂鲤（Notemigonus crysoleucas）。所有双物种组合的……