The American Naturalist
American Society of Naturalists
Using an individual‐based model, Scharf and coworkers showed that ambush predators may encounter prey more frequently than active predators. We show that this surprising result emerges because active predators were oblivious to prey during movement, an assumption that refutes the common conception about active foraging and lessens the key difference between these foraging modes. A revised model confirms that active predators always encounter prey more frequently, unequivocally supporting the authors’ conclusion that the advantage of active predators diminishes as prey moves faster or more directionally. We suggest that movement‐dependent perception quality can determine the relative efficiency of these two foraging modes.
Avgar, T., N. Horvitz, L. Broitman, and R. Nathan (2008) How Movement Properties Affect Prey Encounter Rates of Ambush Versus Active Predators: A comment on Scharf et al. American Naturalist, 172: 593-595