Abstract
The decline of terrestrial predator populations across the globe is altering top-down pressures that drive predator–prey interactions. However, a knowledge gap remains in understanding how removing terrestrial predators affects prey behavior. Using a bifactorial playback experiment, we exposed fox squirrels to predator (red-tailed hawks, coyotes, dogs) and non-predator control (Carolina wren) calls inside terrestrial predator exclosures, accessible to avian predators, and in control areas subject to ambient predation risk. Fox squirrels increased their use of terrestrial predator exclosures, a pattern that corresponded with 3 years of camera trapping. Our findings suggest fox squirrels recognized that exclosures had predictably lower predation risk. However, exclosures had no effect on their immediate behavioral response towards any call, and fox squirrels responded most severely to hawk predator calls. This study shows that anthropogenically driven predator loss creates predictably safer areas (refugia) that prey respond to proactively with increased use. However, the persistence of a lethal avian predator is sufficient to retain a reactive antipredator response towards an immediate predation threat. Some prey may benefit from shifting predator–prey interactions by gaining refugia without sacrificing a sufficient response towards potential predators.
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Data availability
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.
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The code used for analysis of the current study are available from the corresponding author on reasonable request.
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Acknowledgements
We thank the University of Florida and The Jones Center at Ichauway for financial and logistic support. We thank Gail Morris, Jessica Davis, Haley Epperly, and Cat Frock for their field assistance. We thank Kevin Gerena for assistance with scoring videos. We are grateful for the insightful comments provided by Katie Sieving and 3 anonymous reviewers, whose efforts significantly improved this paper.
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This work was supported by funding from The University of Florida funding to RAM, The Jones Center at Ichauway to LMC, and Natural Sciences and Engineering Research Council of Canada Discovery and Research Tools and Instruments Grants to LYZ.
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ADP, LMC, and RAM conceived the experiments, and all the authors contributed to experimental design. ADP carried out data collection, statistical analyses and drafted the manuscript. LMC, MC, LYZ, and RAM critically revised the manuscript.
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All applicable institutional and/or national guidelines for the care and use of animals were followed. All field methods were approved by the University of Florida’s Institutional Animal Care and Use Committee (IACUC# 201709906).
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Communicated by Kathryn E Sieving.
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Potash, A.D., Conner, L.M., Clinchy, M. et al. Prey species increase activity in refugia free of terrestrial predators. Oecologia 201, 661–671 (2023). https://doi.org/10.1007/s00442-023-05350-9
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DOI: https://doi.org/10.1007/s00442-023-05350-9