Optimising a Single Behaviour 2: Stochastic Models of Foraging Behaviour

Abstract

In the previous chapter we looked at a group of models which assume that animals maximise their meanrate of return. However, there are situations when it is not enough to know the meanreturn. In Chapter 3 we assumed that the energetic return from a prey of type 1 was always E_l; we assumed that the return from staying in a patch for T₁s was always E(T₁); and we assumed that travel times (T₁) were constant. As a result the models in Chapter 3 are all deterministic models: once we knew the patch time, we knew the energetic return; once we knew the prey type, we knew its energetic value. In real life it is never quite that easy: the energetic value of a prey type varies from one item to the next; no patch is the same as the next and each offers a different return for a given patch time; and, of course, travel times vary — one patch may be a stone’s throw away, another several miles.