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Hierarchical trade-offs between risk and reward mediated by behavior

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Abstract

Understanding the distribution of individuals in space is a primary concern to ecologists and managers. With the advent of remote monitoring technology, we have been able to answer where individuals are but we often lack an understanding of why they are located in a particular place from a behavioral perspective. Increasingly, ecologists are becoming aware of the crucial role individual behavior may play in ecological processes. The movement of individuals within fragmented landscapes is no exception. We used a dynamic state variable model to explicitly account for the behavioral trade-off between acquiring forage and predation risk in a spatial context. We found that when individuals were able to become behaviorally unavailable for predation within a patch as a result of their energetic state, foraging strategy, or the effectiveness of anti-predator behaviors, they were able to mitigate the potential travel costs associated with the spatial configuration of patches to use riskier patches. However, when this was not possible, patch choice became an effective way of minimizing the risk of predation. Individuals appear to trade-off predation risk and the acquisition of forage in a hierarchical fashion depending on whether or not the spatial arrangement and context of patches constrained their anti-predator behavior. We suggest that a better understanding how patch selection and the behavioral trade-offs associated with predation risk occur at multiple scales may help bridge the gap between animal behavior and landscape ecology.

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Acknowledgments

Thanks to Tomás de Camino-Beck and Erik Noonburg for helpful discussions on dynamic state variable models and stochastic dynamic programming. Thanks also to the Merrill lab, Ron Ydenberg, Mark Lewis, Colleen Cassidy St. Clair, Robert Hudson, Krzysztof Schmidt, Burt Kotler, and an anonymous reviewer for their comments on drafts of this manuscript. Funding to DRV was provided by the Department of Biological Sciences at the University of Alberta and an Industrial NSERC in collaboration with Weyerhaeuser. Funding to EHM was provided by an NSF grant (No. 0078130), Rocky Mountain Elk Foundation, Sunpine Forest Products Ltd., Weyerhaeuser, and the Alberta Conservation Association. Special thanks to the King’s Centre for Visualization in Science for access to computers for these simulations.

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Authors and Affiliations

  1. Department of Biology, The King’s University, Edmonton, AB, Canada, T6B 2H3

    D. R. Visscher

  2. Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada, T6G 2E9

    E. H. Merrill

  3. 2528 Anderson Way SW, Edmonton, AB, Canada, T6W 0L1

    P. K. Martin

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  1. D. R. Visscher
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  2. E. H. Merrill
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Communicated by: Krzysztof Schmidt

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Visscher, D.R., Merrill, E.H. & Martin, P.K. Hierarchical trade-offs between risk and reward mediated by behavior. Mamm Res 62, 129–140 (2017). https://doi.org/10.1007/s13364-016-0290-0

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