Pikas (Ochotona princeps) inhabit areas with talus and forage on surrounding vegetation. Their foraging behavior was consistent with several predictions of central place foraging theory. Intensity of foraging decreased with distance from talus, whereas selectivity increased. Plant abundance and species richness increased with distance from talus. Differences between grazing (direct consumption of plants) and haying (harvesting and caching plants) behaviors appear to reflect differences in costs and benefits between these activities. Higher proportions of forbs and tall grasses were hayed than grazed. When haying, pikas traveled significantly farther into the meadow from the talus border than when grazing. Pikas grazed year round, but hayed only during a restricted time (July through September) when plant biomass had peaked.

Author notes

Present address of NJH: Department of Ecology and Behavioral Biology, University of Minnesota, Minneapolis, MN 55455