Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA.
Biol Lett. 2013 Jun 12;9(4):20130154. doi: 10.1098/rsbl.2013.0154. Print 2013 Aug 23.
Predation can be an important agent of natural selection shaping parental care behaviours, and can also favour behavioural plasticity. Parent birds often decrease the rate that they visit the nest to provision offspring when perceived risk is high. Yet, the plasticity of such responses may differ among species as a function of either their relative risk of predation, or the mean rate of provisioning. Here, we report parental provisioning responses to experimental increases in the perceived risk of predation. We tested responses of 10 species of bird in north temperate Arizona and subtropical Argentina that differed in their ambient risk of predation. All species decreased provisioning rates in response to the nest predator but not to a control. However, provisioning rates decreased more in species that had greater ambient risk of predation on natural nests. These results support theoretical predictions that the extent of plasticity of a trait that is sensitive to nest predation risk should vary among species in accordance with predation risk.
捕食是自然选择塑造亲代抚育行为的重要因素，也有利于行为可塑性。当感知到风险较高时，亲鸟通常会减少给巢中幼鸟喂食的频率。然而，这种反应的可塑性可能因物种而异，这取决于它们遭受捕食的相对风险或平均喂食率。在这里，我们报告了亲鸟对捕食风险感知增加的实验性供应反应。我们测试了北温带亚利桑那州和亚热带阿根廷的 10 种鸟类对巢捕食者的反应，这些鸟类在环境捕食风险方面存在差异。所有物种在受到巢捕食者的影响后，都会降低喂食率，但对对照物没有反应。然而，在自然巢中面临更大捕食风险的物种中，喂食率下降得更多。这些结果支持了理论预测，即对巢捕食风险敏感的性状的可塑性程度应该根据捕食风险在物种间有所不同。
