COS 97-4 - Temporal clustering of prey in wildlife passages provides no evidence of a prey‑trap

Background/Question/Methods

Wildlife passages are structures built across roads to facilitate wildlife movement and prevent wildlife

collisions with vehicles. The efficacy of these structures could be reduced if they funnel prey into

confined spaces at predictable locations that are exploited by predators. We tested the so-called preytrap

hypothesis using remote cameras in 17 wildlife passages in Quebec, Canada from 2012 to 2015 by

measuring the temporal occurrence of nine small and medium-sized mammal taxa (< 30 kg) that we

classified as predators and prey. We predicted that the occurrence of a prey-trap would be evidenced

by greater frequencies and shorter latencies of sequences in which predators followed prey, relative to

prey–prey sequences.

Results/Conclusions

Our results did not support the prey-trap hypothesis; observed prey–predator

sequences showed no difference or were less frequent than expected, even when prey were unusually

abundant or rare or at sites with higher proportions of predators. Prey–predator latencies were also

1.7 times longer than prey–prey sequences. These results reveal temporal clustering of prey that may

dilute predation risk inside wildlife passages. We encourage continued use of wildlife passages as

mitigation tools.