The Payoffs to Producing and Scrounging: What Happens when Patches are Divisible?

Abstract

Abstract Although many group‐foraging models assume that all individuals search for and share their food equally, most documented instances of group foraging exhibit specialized use of producer and scrounger strategies. In addition, many of the studies have focused on groups with strong individual asymmetries exploiting food that is not easily divisible. In the present study we describe individual foraging behavior of relatively nonaggressive flock foragers exploiting divisible clumps of food. Two experiments, one with flocks of spice finches and another with flocks of zebra finches, suggest that divisibility of food patches may have important consequences for social foraging behavior. Neither dominance nor the distribution and quality of food patches affect the relative advantage that producing individuals enjoy over those that scrounge. Specialized producers and scroungers are absent from flocks of both species. Systems where patches are shared may differ fundamentally from those where patches are monopolized by scroungers.