Activity Patterns Structure Food Web Interactions Through Time

Abstract

Many mobile animals move to locate and consume resources, making energy gain and growth dependent on activity. Yet the role of activity in shaping predator-prey interactions in food webs has not been broadly considered. Here, we synthesize empirical examples to examine how three activity traits (mean, variance, and timing) vary among taxa (fish, mammals, birds) and between predators and prey across temporal scales. We then use predator-prey models to explore how these diverse activity patterns influence stability. Motivated by emerging activity patterns, our theory shows that fluctuating activity rates can drive predator-prey interaction strengths with major consequences for stability. Future research is needed on activity trait patterning, links between activity and attack rates, and the consequences of activity for predator-prey interactions to whole food webs. This is especially critical as human-driven changes to abiotic cues increasingly alter animal activity rates and may rewire food webs.