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bioRxiv · 10.64898/2026.07.21.739907

Prey age modifies risk-taking behavior in a multi-predator environment

Smith, B. J.·Avgar, T.·Peacor, S. D.·Stahler, D. R.·Metz, M. C.·Rabe, J. W.·Binder, W.·MacNulty, D. R.
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Abstract

Many species of animals undergo senescence, impacting predator-prey relationships, yet how senescing prey adjust their risk-taking behavior is poorly understood. We used integrated step selection analysis to quantify risk-taking from empirical data. A graphical framework of age-dependent adaptive risk-taking predicted - and our empirical analysis found - a reduction in female elk (Cervus canadensis) risk-taking with age toward wolves (Canis lupus) but not cougars (Puma concolor), underscoring the role of predator hunting mode in ecological dynamics. We estimated average risk-taking toward wolves would be 42% lower in a population with median age 10 versus 4 years, highlighting how a prey populations age structure likely impacts risk-induced trait responses and the potential emergence of predation-risk effects. Our findings suggest that altered risk-taking may be an adaptive behavioral shift rather than a passive consequence of physical decline. Such adaptive changes to risk-taking may represent an underappreciated link between individual behavior and community-level coexistence.

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Smith, B. J., Avgar, T., Peacor, S. D., Stahler, D. R., Metz, M. C., Rabe, J. W., Binder, W., MacNulty, D. R.. 2026-07-22. Prey age modifies risk-taking behavior in a multi-predator environment. https://doi.org/10.64898/2026.07.21.739907

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