Non-consumptive effects of predation

Fear as an organizing principle…

Predation is a powerful ecological force whose effects scale up from individuals to populations to ecosystems.  This occurs, in part, because of the numerical effect of removing individuals through consumptive predation but is also facilitated by the non-consumptive effects (NCEs) of predation.  In this case the mere threat of predation changes the behaviour of individual prey.  A trade-off results from the prey's attempt to balance the acquisition of energy and the avoidance of predation.  As a result individual fitness declines which scales to changes in populations and their influence on the ecosystem.  In addition, human activity and disturbance may be perceived by prey as a form of risk or fear, resulting in similar changes in behaviour with their resultant higher level consequences.

I have worked on this issue from a number of angles:

• Modelling trade-offs with dynamic state variable models

• Fitness consequences of predation in porcupine

• Behaviour altered by human disturbance

• Fear and parasites

This work is being done in collaboration with:

• Evelyn Merrill (University of Alberta)

• Phil DeWitt (Ontario Ministry of Natural Resources)

• Collin Horn (University of Alberta)