The context dependence of non-consumptive predator effects
Aaron J. Wirsing1, Michael R. Heithaus2, Joel S. Brown3,4, Burt P. Kotler5, Oswald J. Schmitz6
1School of Environmental and Forest Sciences, Box 352100, University of Washington
Seattle, WA 98195, USA, wirsinga@uw.edu (corresponding author)
2Department of Biological Sciences, Marine Sciences Program, 3000 NE 151st St, Florida International University, North Miami, FL 33181, USA, heithaus@fiu.edu
3Department of Biological Sciences, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL 60607, USA, squirrel@darwiniandynamics.org
4Department of Integrated Mathematical Oncology, Moffitt Cancer Center, 12902 Magnolia Dr., Tampa, FL, 33613, USA
5Mitrani Department of Desert Ecology, Jacob Blaustein Institutes for Desert Research
84990 Midreshet, Ben-Gurion University of the Negev, Ben-Gurion, Israel, kotler@bgu.ac.il
6School of Forestry and Environmental Studies, Yale University, 195 Prospect Street, New Haven, CT 06511, USA, Oswald.schmitz@yale.edu
Running head : Context dependence of NCEs
Statement of authorship : AW and MH conceived of the idea for the paper. All authors wrote the manuscript as a team and contributed substantially to revisions.
Data accessibility statement : Should the manuscript be accepted, the data supporting the results will be archived in the dryad digital repository.
Counts : Abstract (195); Main text (7489); Cited references (162); Tables (0); Figures (4); Text boxes (3)
Key Words : anti-predator behavior; contingency; escape; evasion landscape; habitat domain; hunting mode; predation risk; predator-prey interactions; risk effects; top-down effects; trade-offs
Abstract. – Non-consumptive predator effects (NCEs) are now widely recognized for their capacity to shape ecosystem structure and function. Yet, forecasting the propagation of these predator-induced trait changes through particular communities remains a challenge. Accordingly, focusing on plasticity in prey anti-predator behaviors, we conceptualize the multi-stage process by which predators trigger direct and indirect NCEs, review and distill potential drivers of contingencies into three key categories (properties of the prey, predator, and setting), and then provide a general framework for predicting both the nature and strength of direct NCEs. Our review underscores the myriad factors that can generate NCE contingencies while guiding how research might better anticipate and account for them. Moreover, our synthesis highlights the value of mapping both habitat domains and prey-specific patterns of evasion success (“evasion landscapes”) as the basis for predicting how direct NCEs are likely to manifest in any particular community. Looking ahead, we highlight two key knowledge gaps that continue to impede a comprehensive understanding of non-consumptive predator-prey interactions and their ecosystem consequences; namely, insufficient empirical exploration of 1) context-dependent indirect NCEs and 2) the ways in which direct and indirect NCEs are shaped interactively by multiple drivers of context dependence.