Predators affect prey by consuming them (consumptive effects) as well as by inducing changes in prey behavior or morphology (non-consumptive effects). Although ecologists are increasingly aware of the importance of non-consumptive effects, less is known about the consequences of non-consumptive effects on the spatial dynamics of predators and prey.

I have been working as part of an NCEAS working group organized by Evan Preisser and Dan Bolnick to determine the relative importance of consumptive and non-consumptive effects in ecological systems.

Although this work is ongoing, several interesting insights have already emerged. For example, by affecting prey movement behavior, predators can alter the outcome of competition in prey metacommunities, foster or thwart biological invasions, and ultimately determine prey persistence. An extensive metaanalysis suggests that classification of predators by their hunting mode and habitat domain can be an effective way of predicting the relative importance of consumptive vs. non-consumptive effects of predators on prey.

Orrock, J. L., J. H. Grabowski, S. D. Peacor, B. L. Peckarsky, E. L. Preisser, A. Sih, and E. E. Werner.  2008.  Consumptive and non-consumptive effects of predators on metacommunities of competing prey.
Ecology 89: 2426-2435. [Reprint]

Peckarsky, B. L., D. I. Bolnick, L. M. Dill, J. H. Grabowski, B. Luttbeg, J. L. Orrock, S. D. Peacor, E. L. Preisser, O. J. Schmitz, and G. C. Trussell.  2008. Revisiting the classics: Considering non-consumptive effects in textbook examples of predator-prey interactions.
Ecology 89: 2416-2425. [Reprint]

Preisser, E. L., J. L. Orrock, and O. J. Schmitz.  2007.  Predator hunting mode and habitat domain affect the strength of non-consumptive effects in predator-prey interactions.
Ecology 88: 2744-2751. [Reprint]