Consequences of the dynamics of behavioural choice for predator-prey population dynamics

The dynamics of a series of two-prey-one-predator models of adaptively foraging predators are investigated. Two general classes of models are examined: instantaneous choice models, where the probability of attacking poorer prey is adjusted instantaneously based on current prey densities, and dynamic choice models, where the probability of attacking poorer prey is a dynamic variable. Results indicate that the predictions of the two classes of models differ in several ecologically important quantities. Dynamic choice models commonly predict complex cycles and chaotic dynamics, whereas instantaneous choice models do not. Furthermore, the two classes of models often predict different average population densities and indirect interactions between the prey species. A variety of alternative models of dynamic diet choice are also considered. Overall, the results caution against the use of instantaneous diet choice, and suggest that considering diet choice as a dynamic phenomenon may provide new insights into the population dynamics of adaptive foragers.