Predator-prey temporal niche partitioning under human disturbance: a meta-analysis

Human disturbances are modifying animal behavior in ecosystems worldwide, with the potential to reshape species interactions. For instance, human-induced shifts in diel activity may disrupt the alignment of daily activity patterns between interacting species and destabilize temporal niche partitioning. To test this hypothesis, we leverage a global meta-analysis on the effects of human disturbance on diel activity and overlap of 480 mammalian predator-prey and intraguild predator dyads from 57 studies. We demonstrate that human disturbance has no overall effect on temporal overlap. Instead, the body mass ratios between dominant species and subordinate species shape the influence of human disturbance. When subordinates are larger than dominant species, humans compress the temporal niche (i.e., higher diel overlap), but when dominant species are larger than subordinate species, humans expand the temporal niche (i.e., lower diel overlap). These results suggest that larger bodied mammals "lose" the temporal predator-prey response race under human disturbance, with large predators experiencing less overlap with their prey, and large prey facing more overlap with their predators. As the human footprint expands globally, we can expect continued alterations to the animal temporal niche, with consequences for species interactions, population persistence, community structure, and evolutionary dynamics.