Rates of Seed Harvest by Two Species of Gerbilline Rodents

We measured rates of seed harvest by two coexisting rodent species, Gerbillus allenbyi and G. pyramidum, in the laboratory. Both species experienced diminishing returns to harvest rate with increasing foraging time. G. pyramidum had a significantly lower handling time, which may result in an advantage over G. allenbyi in foraging efficiency at high densities of seeds. The smaller-bodied G. allenbyi had a slightly but not significantly higher rate of encountering seeds, which may give this species an advantage in foraging at low densities of seeds.