1936] 



MAMMALS OF OREGON 



147 



CITBLLUS COLUMBIANUS COLUMBIANUS (ORD) 

 COLUMBIAN GROUND SQUIRREL; BURROWING SQUIRREL 



Arctomys columbianus Ord, Guthrie's Geogr., 2d Amer. ed., 2, p. 292, 1815, from 

 description by Lewis and Clark. 



Type locality. Camas Prairie on Jim Ford Creek about 7 miles northeast of 

 the mouth of Lolo Fork of Clearwater River, Idaho. 



General cliaracters. Body large and heavy (pi. 29. B) ; tail short, wide and 

 bushy; ears short; soles half naked, heels hairy; cheek pouches small and 

 little used ; fur soft and lax with coarse outer hairs. Summer pelage, upper 

 parts coarsely grizzled brownish gray, lighter gray across top of neck; face, 

 feet, and legs, and sometimes whole top of tail deep rufous or rusty brown; 

 tail usually dark gray or rufous above and below with three concealed black 

 lines along each side and around tip and with tips of long hairs frosted with 

 white or fulvous; lower parts pale fulvous, becoming deep fulvous or rusty 

 brown in anal region. Winter pelage and young essentially the same. 



Measurements. Average of 

 10 males: Total length, 375 

 mm; tail, 107; foot, 54; ear 

 (dry) from notch, 13, from 

 crown, 6. Weight of adults 

 about 1 pound ; of very large 

 males, 1% pounds. 



Distribution and habi- 

 tat. From northeastern 

 Oregon and central Idaho 

 the range of these big 

 ground squirrels extends 

 northward over Idaho, 

 eastern Washington, and 

 western Montana into 

 British Columbia and Al- 

 berta (fig. 27) . They occu- 

 py Canadian, Transition, 

 and Hudsonian Zones, mainly in the open country but often in 

 brushy or sparsely timbered areas. They are rarely found in heavy 

 timber but seem to find all the little meadows and parks scattered 

 through the forest. As the Canadian is generally the zone of heavy 

 forest, they are largely crowded into the more open Hudsonian above 

 or onto the edges of the Transition plains below. In Oregon- they 

 occupy the Blue Mountain section but do not reach into the south- 

 western part of this plateau. Although they are numerous locally 

 they are not generally distributed over their range. 



General habits. These burrowing squirrels were well named by 

 Lewis and Clark, who first made them known to science, for they 

 live the greater part of their lives underground in extensive bur- 

 rows. Although almost as sociable as prairie dogs, they are less 

 colonial in habits and are often found alone or in families, scattered 

 far apart. In favorite sections, however, they are so numerous and 

 so noisy in their barking, whistling, squeaking calls as to give the 

 impression of community interdependence. 



Their call note is usually a short, sharp whistle, or chirp, some- 

 times repeated at intervals of about 1 second for several minutes 

 at a time, one and then another taking it up until in a populous part 

 of their range one or several may be heard much of the time during 



FIGURE 27. Range of the Columbian ground squirrel, 

 Citellus columlHanus columbianus, in Oregon. 



