Remarks.—Citellus w. loringi allegedly differs from typical washingtoni in smaller size. The specimens collected by us from within the range of loringi are as large as those from farther south. C. w. loringi is regarded as a synonym of C. w. washingtoni.
Description.—The Washington ground squirrel closely resembles the Townsend ground squirrel in size and appearance. It differs principally in color. The upper parts are brownish gray marked with distinct white spots, and the underparts are buffy. The face, thighs and tail are dull reddish.
This species is closely related to the Townsend ground squirrel but its habitat is more varied. It is most common in areas of low sage bushes surrounded by grasslands and on extensive grasslands, but occurs also in sandy places, wheat fields, and rocky hillsides. The animals live in colonies, in some places 50 or more individuals to the acre. They occur also as scattered individuals or small colonies in smaller areas of suitable habitat. For example, along the highway from Farmer, Douglas County, to Waterville, a distance of 15 miles, a band of natural grass, 50 feet or less in width, lies between the road and the extensive wheat fields beyond. This strip of natural cover possessed about one Citellus to each 200 feet along most of its length. The squirrels were often seen sitting on rolls of wire drift fence, used to keep snow drifts from the road in winter but in summer rolled into bundles 3 feet in diameter and left standing at intervals of one each 100 feet. The squirrels had constructed their burrow entrances beneath these rolls and used the rolls as look-out posts. At my approach they would dodge into the rolls of wire and, unless scared, remained in the wire roll. By approaching carefully and overturning the rolls I was able to trap and capture a good series of living specimens.
Burrows, nests, habits, and food of this species seem identical to those of townsendii. Aestivation dates seem to be the same ([Scheffer], 1941: 270-279). The hibernation of this species has been discussed in detail by Svhila (1939: 6-10). Food species listed by [Scheffer] at Wallula ([Howell], 1938: 8) are identical to those of townsendii at Kennewick, across the Columbia River (see account of townsendii).
[Scheffer] (1941: 270-279) examined 26 pregnant females of this species and found the fetuses to vary from 5 to 11 in number, with an average of 8.
Citellus columbianus (Ord)
Columbian ground squirrel
Description.—The Columbian ground squirrel has the general body proportions, large head, large eyes, low, rounded ears, plump body and short tail of the Townsend ground squirrel, but is much larger. The head and body of an adult measure about 10 inches and the tail about 4 inches. The upper parts are grayish buff mottled with round white dots. The underparts and forefeet are pale ochraceous. The back of the head and neck are gray. The face, thighs and tail are reddish.
The Columbian ground squirrel occupies inland mountainous areas from central British Columbia to central Oregon and Idaho and from eastern Washington and Oregon to western Montana and southwestern Alberta. It is closely related to the arctic ground squirrels of the Citellus parryii group, which are in turn related to the Siberian forms, buxtoni and stejnegeri.
The habitat of the Columbian ground squirrel is varied but is usually more humid than that of the Townsend and Washington ground squirrels. The most arid of the lands occupied by them in Washington are the grasslands and wheat fields of the Poulouse country and the eastern border of the state. In northeastern Washington they live in meadows and grasslands in the valleys, in openings in the coniferous forest at higher altitudes and in parks and alpine meadows almost to timber-line on the mountains. Some individuals were in brushy places or even in forests, far from grassy clearings. Near Republic, Ferry County, a Columbian ground squirrel was killed as it ran along a log in dense larch woods. Its burrows were found in a tangle of brush and fallen logs. No clearings, meadow or grassland existed nearby. Narrow bands of cleared land beside roads and railroad tracks are extensively used by these squirrels. Where small meadows or pastures occur, this species lives in dense colonies. If grasslands are extensive it lives in loose colonies, often with considerable distances between individual burrow systems. In the mountains the squirrels are scattered or live in small groups.
Burrows of the Columbian ground squirrel are often constructed in the open. Mouths of burrows, especially if the animals are living in colonies, usually are marked by a large pile of excavated earth. If, however, there is some large object on the surface of the ground, such as a stone, stump, or log, the entrance to the burrow is located beside this. Such objects are often undermined and made to settle, eventually becoming buried. The squirrels live under houses, and the yards of abandoned ranch buildings are often infested with them.