Optimal prey choice in a daily foraging bout

This study investigates the optimal daily foraging strategy of predators that encounter two distinct types of prey. While the classical prey model is derived under the assumption of an infinite foraging duration, a stochastic simulation model was developed to incorporate finite foraging durations. The classical prey model yields two major predictions: the zero-one rule and the independence of the optimal strategy from the density of the less profitable prey. In contrast, the simulation model revealed that the optimal strategy involves partial preference (a deviation from the zero-one rule) and depends on the density of the less profitable prey. Thus, neither key prediction of the classical prey model held under finite foraging durations. Because empirical studies have also frequently failed to support the classical model, previous theoretical studies have attributed these discrepancies to species-specific biological complexities, such as predator cognitive limitations. The present simulation suggests that finite foraging durations, common to all species, can by themselves account for some of these deviations. Moreover, incorporating finite foraging durations may further alter the outcomes of models that include detailed biological mechanisms if those models remain based on an infinite foraging duration.