Amur tiger urine increases small -bodied mesopred

Apex predators exert dual effects on mesopredators, including both suppression through lethal encounters and fear, as well as facilitation through providing food via prey remains. While large-scale studies on how apex predators influence mesopredator distributions are abundant, research on how apex predators affect mesopredators at the fine scale—particularly their specific behaviors—remains limited.Using Amur tiger urine as an apex predator cue and captive bird eggs—which served as a food source for mesopredators with minimal odor interference—we evaluated the effects of this apex predator scent on the foraging behavior of mesopredators in northeastern China. Our results demonstrate that tiger urine attracted small-bodied mesopredators, increasing their visitation speed and accelerating nest predation. Asian badgers in particular perceived tiger urine as a food resource cue, stimulating their exploration and squat-marking behavior improving egg detection and predation. This study focuses on the behavioral impacts of tiger urine on small-bodied mesopredators, revealing how top predator signals shape the foraging behavior of small-bodied mesopredators at the local scale. Specifically, top predators may exert greater attractive effects than fear effects on mesopredators with significantly smaller body sizes—a finding that deviates from the traditional paradigm that "top predators generally suppress mesopredators". Ultimately, this study deepens our understanding of the complex interactions between top predators and mesopredators, and provides references for ecological regulation (e.g., regulation of lower-trophic-level species) in future species conservation efforts.