Belding’s ground squirrel [SPERMOPHILUS BELDINGI]

Few animals enliven high Sierra Nevada meadows quite like the energetic little Belding’s ground squirrels, which whistle loudly at passing hikers all summer long. Because they often stand perfectly upright like the pickets -- or hitching posts -- used to tether horses, they have the common nickname “picket pins.” Males first emerge from melting snowbanks in late spring. When females emerge several weeks later, they are sexually receptive for only a few hours, so males fight fiercely, even to the death, for an opportunity to mate. In contrast, females live in cooperative clans of close relatives and help each other watch for predators by giving alarm calls. Females frequently “kiss” as a way of smelling each other to verify their kin relationships. Bumbling youngsters appear in late July and must eat enough grass stems and seeds to increase their weight four- to sixfold before hibernation.

NATURAL HISTORY

These rodents sleep for eight months, one of the longest hibernation periods of any North American animal. Winter is a brutal time, however, and as many as 70% of the adults and 90% of the juveniles perish during hibernation. More perish in late spring snowstorms after they emerge.

KEY CHARACTERISTICS

A foot-long squirrel with a short, skinny tail, gray coloration and a red-brown band along its back.