Graduate Group in Ecology, University of California Davis, Davis, California, 95616, USA.
Department of Entomology and Nematology, University of California Davis, Davis, California, 95616, USA.
Ecology. 2018 Jul;99(7):1584-1590. doi: 10.1002/ecy.2356. Epub 2018 May 16.
Climate change can have strong effects on species interactions and community structure. Temperature-dependent effects on predator-prey interactions are a major mechanism through which these effects occur. To understand the net effects of predator attack rates and dynamic windows of prey vulnerability, we examined the impacts of temperature on the interaction of a caterpillar (Arctia virginalis) and its ant predator (Formica lasioides). We conducted field experiments to examine attack rates on caterpillars relative to temperature, ant abundance, and body size, and laboratory experiments to determine the effects of temperature on caterpillar growth. We modeled temperature-dependent survival based on the integrated effects of temperature-dependent growth and temperature- and size-dependent predation. Attack rates on caterpillars increased with warming and ant recruitment, but decreased with caterpillar size. Caterpillar growth rates increased with temperature, narrowing the window of vulnerability. The model predicted that net caterpillar survival would decrease with temperature, suggesting that A. virginalis populations could be depressed with future climate warming. Theoretical work suggests that the net outcome of predator-prey interactions with increasing temperature depends on the respective responses of interacting species in terms of velocity across space, whereas the present study suggests the importance of effects of temperature on prey window of vulnerability, or "velocity" across time.
气候变化对物种相互作用和群落结构有很强的影响。温度对捕食者-猎物相互作用的影响是这些影响发生的主要机制。为了了解捕食者攻击率和猎物易损性的动态窗口的净效应，我们研究了温度对毛毛虫（Arctia virginalis）和其蚂蚁捕食者（Formica lasioides）相互作用的影响。我们进行了野外实验，以研究相对于温度、蚂蚁丰度和体型的毛毛虫的攻击率，以及实验室实验，以确定温度对毛毛虫生长的影响。我们基于温度依赖性生长和温度和大小依赖性捕食的综合影响来模拟温度依赖性生存。毛毛虫的攻击率随升温、蚂蚁招募和毛毛虫体型的增加而增加。毛毛虫的生长率随温度升高而增加，从而缩小了易损窗口。该模型预测，毛毛虫的净生存能力将随温度下降而下降，这表明未来气候变暖可能会导致 A. virginalis 种群减少。理论研究表明，随着温度的升高，捕食者-猎物相互作用的净结果取决于相互作用的物种在空间上的速度的各自响应，而本研究则表明温度对猎物易损窗口或“时间上的速度”的影响的重要性。
