Data from: Predator personality structures prey communities and trophic cascades

Intraspecific variation is central to our understanding of evolution and population ecology, yet its consequences for community ecology are poorly understood. Animal personality—consistent individual differences in suites of behaviors – may be particularly important for trophic dynamics, where predator personality can determine activity rates and patterns of attack. We used mesocosms with aquatic food webs in which the top predator (dragonfly nymphs) varied in activity and subsequent attack rates on zooplankton, and tested the effects of predator personality. We found support for four hypotheses: 1) active predators disproportionately reduce the abundance of prey, 2) active predators select for predator-resistant prey species, 3) active predators strengthen trophic cascades (increase phytoplankton abundance), and 4) active predators are more likely to cannibalize one another, weakening all other trends when at high densities. These results suggest that intraspecific variation in predator personality is an important determinant of prey abundance, community composition, and trophic cascades.种内变异是我们理解进化与种群生态学的核心所在，但其对群落生态学的影响却尚缺乏充分研究。动物个性（Animal personality）——即个体间稳定存在的行为综合征差异——或许对营养动态尤为关键：捕食者的个性可决定其活动速率与攻击模式。本研究采用搭载水生食物网的中型实验生态系统（mesocosms），其中顶级捕食者为蜻蜓稚虫，其活动水平与对浮游动物的后续攻击速率存在差异，以此检验捕食者个性的生态效应。本研究验证了四项假说：1）活跃型捕食者会不成比例地降低猎物种群丰度；2）活跃型捕食者会筛选出具有捕食抗性的猎物物种；3）活跃型捕食者会强化营养级联效应（提升浮游植物丰度）；4）高密度条件下，活跃型捕食者更易发生同类相食，从而削弱其余所有观测趋势。上述结果表明，捕食者个性的种内变异是决定猎物丰度、群落组成与营养级联效应的关键因素。