Foraging in flocks: non-spatial models may neglect important costs

Several previous mathematical models of group foraging assume (1) that the time taken to find food patches is inversely proportional to group size and (2) that the time taken for others to travel to a discovered patch is negligible compared to the time taken for its discovery. These non-spatial models effectively consider that searching individuals and food patches are always homogeneously mixed. Using a spatially-explicit model, I show that the two assumptions above are often not realistic. For this reason, I argue for the greater consideration of spatial effects in future studies of group foraging.