The effects of local enhancement on mean food uptake rate

Abstract

A forager searching for food can cue on a distant feeding group to infer the location of a food patch it could share. This behavior, known as local enhancement, reduces variance in time between meals, but its effect on long-term uptake rate is less resolved. An influential simulation study concluded that benefits through reduced variance would be mitigated by reduced long-term uptake rate. This cost comes about through spatial clumping of foragers, leading to overlapping search paths and, thus, reduced aggregate patch finding. Here, we revise the previous model and submit it to more extensive investigation. Our simulations reveal that local enhancement can increase mean uptake rates but only when food patches are scarce in the environment. Contrary to previous speculations, we do not find that high-value patches or strong heterogeneity in patch quality strengthens this potential added benefit to local enhancement. As such, our simulations delineate situations where selection pressures based on maximizing long-term uptake rate act antagonistically or synergistically with starvation-avoidance through reduced temporal variance in feeding.