Figure 7.

Depleting environments with ‘known’ versus ‘unknown’ patch resource values. In the ‘known’ case, the forager knows the patch type and initial resource yield rate upon arrival, whereas in the ‘unknown’ case the forager must infer the path type. Patch-leaving strategies in the unknown case approach those of the known case in the high-chunk count limit. (a) Total resource intake rate $R^{{\lambda }_{\theta }}$ as a function of the estimated yield rate λ_θ at which the observer departs a patch. For low initial resource levels $m_0^H$ and $m_0^L$, $R^{{\lambda }_{\theta }}$ near the optimum (dots) deviates between the case of initially known patch type (black) versus initially unknown (blue). Both thresholds are less than the MVT prediction owing to the discreteness of resource encounters. (b) Resource intake rates of the known/unknown cases converge at higher initial resource levels. (c) Deviations in optimal resource intake rate between known and unknown cases are due to less certainty $\overline{P}({\lambda }_j)$ (grey line) about the patch yield rate upon departure, leading the observer to stay in low-yield patches too long (blue line) and leave high-yield patches too soon (red line). Other parameters are ρ = 1, τ = 5 and p_H = 0.5. Mean rates and departure times in the unknown patch case were computed from 10⁶ Monte Carlo simulations.