Effects of group size

Benefits of reduced search time reach asymptote as search group size increases; members eventually overlap areas and interfere with one another. Increased size will increase energy needs that will eventually exceed energy gained by being in a group if too large. Avoiding predators, if group too large group vigilance not maintained and members will ‘cheat’. Optimal group size differs from species to species as well as time, patch quality and predation pressure. Temporary groups more often closer to optimal size than permeant as permeant change with births and increase steadily.