1936] MAMMALS OF OREGON 257 



Measurements. Typical males: Total length, 209 mm; tail, 66; foot, 28; 

 ear dry), 6. Females : 202 ; 66 ; 28. 



Distribution and habitat. These are mountain pocket gophers 

 inhabiting the Cascades, Siskiyou, and Trinity Mountains of Oregon 

 and northern California, mainly in Canadian Zone, but in places 

 reaching into Hudsonian (fig. 58). While living mainly in the 

 meadows and open parklike places, they are often found scattered 

 through the more open timber. 



General habits. The small size of these pocket gophers is generally 

 compensated by the greater abundance of individuals in the mountain 

 parks and meadows, where they burrow actively, not only during 

 the short summers, but all winter under the deep snows. In spring 

 when the snow disappears long snakelike plugs of earth lie over the 

 surface of the ground, where the excavations from deeper down have 

 been pushed into snow tunnels on the surface and left to freeze and 

 harden. In melting and disintegrating in spring these earth coils 

 show all the bits of bark, stems, wood, and refuse of the under- 

 ground food pushed out with the earth and help to explain how the 

 gophers can keep active during the winter. They sometimes store 

 food in the burrows but do not become fat in the fall and evidently 

 do not regularly hibernate, 



Breeding habits. These pocket gophers have normally the usual 

 number of 8 mammae, but occasionally an extra pair of pectoral, 

 making 10. Little is known from actual observation of their breed- 

 ing habits, but young of various sizes are taken in traps all through 

 the summer, which would indicate several litters during a season. 

 Judging from other species 4 to 8 would be the probable number of 

 young in a litter. 



Food habits. In summer their large stomachs are generally found 

 filled with both green vegetation and the white pulp from roots, 

 bulbs, and tubers, with occasionally spots of bright colors that 

 serve to identify local flowers or bright-colored roots. The surface 

 vegetation is gathered at the openings of their burrows before the 

 earth is thrown out, or at openings made merely to reach the plants 

 and then closed without throwing out a mound. In camp near 

 Three Sisters one came up in the middle of the tent where the 

 writer was at work, quietly preparing specimens. There was a 

 muffled gnawing or scratching, then an aster stem began to move, 

 and soon the tip of a little brown nose showed in the middle of a 

 tuft of short grass, and the hole was quickly enlarged to allow the 

 pocket gopher's head to protrude. The aster stem was cut off and 

 drawn down into the burrow ; then some wide leaves and some grass 

 blades were cut and stuffed into the pockets. Within a minute a 

 good meal was thus gathered and the hole securely plugged from 

 within. The pocket gopher safely enjoyed its morning meal below. 



Economic status. These mountain pocket gophers are often so nu- 

 merous in the mellow-soil parks that their mounds cover from 5 to 10 

 percent of the surface, and the burrows 6 inches to a foot below 

 the surface are so numerous that one's feet keep breaking into 

 them, while cattle, sheep, and deer tracks often make so many open- 

 ings that the gophers are kept busy closing them. The mounds are 

 usually small, a few quarts to a half bushel of earth in a place at 



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