Montana Field Guide

The Columbian ground squirrel is easily distinguished from other Montana ground squirrels by its larger size and distinctive coloration. An average adult weighs more than a pound. Its head and body measure 10 to 12 inches in length. The tail is 3 to 5 inches long and tends to be bushy, particularly when the squirrrel is excited. Reddish-brown fur is found on the nose, forelegs, and hindquarters. The back and upper limbs are mottled gray and brown (Montana Dept. of Agriculture 1985).

Non-migratory.

Intermontane valleys, open woodland, subalpine meadows, even alpine tundra (Hoffmann and Pattie 1968). Subalpine basins, clearcuts, and other disturbed areas (Ramirez and Hornocker 1981). At high elevations, may use rockslides/forage in meadows. Prefers g-lands & sedges.

In early summer: grasses, leafy vegetation, and bulbs. May increase use of fruits and seeds as season progresses. Uses a small amount of animal matter: insects, fish, carrion.

Allopatric distrib. with S. richardsonii from Canada border. South to MADI and BEAV, S. richardsonii and S. columbianus along with S. armatus in BEAV (Hoffmann and Pattie 1969). Four species sympatry (prev. listed 3 sp + S. elegans in MADI).

Breeding dates vary depending on location/elevation. April at lower elevations. As late as June at higher elevations. One litter per year. Young reach full growth during second season.