Montana Field Guide

Northern Pocket Gopher - Thomomys talpoides

The northern pocket gopher, so named for its large, external, fur-lined cheek pouches, measures about 8 inches length in total, with a short, nearly hairless tail of 2 1/2 inches. Its weight varies from 2 3/4 to 4 3/5 ounces (Burt and Grossenheider). It has soft reddish-brown upper fur and a dark gray underside. In the eastern areas of its distribution, the upper fur becomes lighter brown with an orangish or yellowish cast (Foresman 2001). The fur can be smoothed forward or backward (Zeveloff 1988). Black patches surround the small, nearly hidden ears. Well-developed jaw, neck, forearm, and shoulder muscles give this rodent a solid appearance, while narrow hips (Kritzman 1977) and loose skin enable it to turn 180 degrees in its tunnels (Foresman 2001). It is equipped with long curved claws on three digits of its forepaws (Foresman 2001) and sharply curved, always exposed, yellowish incisors for digging and cutting. The feet are whitish and the incisors may be white-tipped. There may also be white markings under the chin (Zeveloff 1988). The pocket gopher has 20 teeth with a shallow groove near the inner side of each upper incisor (Burt and Grossenheider 1964). It begins a gradual molting in spring, marked by a moving band of fur which progresses from the blackish nose to base of tail by the end of the summer.

Montana Range

Non-migratory.

Uses a wide variety of habitats--from cultivated fields and prairie to alpine meadows (Jones et al. 1983). It avoids only dense forests, very shallow, rocky soils, and areas with poor snow cover where the soil frezes over (Hoffman and Pattie 1968).

In addition to the mainstay of underground plant parts, may occasionally use leaves of forbs, but only within close range of a burrow opening (Jones et al. 1983).

Pockets are used for transporting food. Lips can be closed behind incisors. Short, sensitive, sparsely-haired tail used for guidance when traveling backwards in burrow. Lower level for nest & storage, upper for foraging (Jones et al. 1983).

Young are weaned at 40 days. Dispersal (at 2 months) may be above ground or below ground. Reproductively mature at 1 year (Jones et al. 1983).