Description.—The pika is of guinea-pig size, with a short, chunky body about 200 mm. in length. The tail is represented externally merely by a tuft of white fur. The short, wide head has large, circular ears, large black eyes, and long whiskers. The legs are short and the soles of the feet are furred. The color of the Washington races varies from grayish-yellow to dark reddish brown. Like rabbits, all pikas have two pairs of upper incisors. The second pair, located just in back of the first, is small and delicate.
Ochotona is a wide-ranging genus with many more species in Asia and extreme eastern Europe than in North America. Three races of the species princeps occur in the state of Washington, where they are confined to the Cascade, Kettle River, and Pend Oreille Mountains. The ranges of all three races extend northward into British Columbia; one (brunnescens) occurs also in Oregon, and one (cuppes) in Idaho.
In Washington pikas live only in talus slides and rock piles, where they find refuge from most of the carnivores that prey on small mammals. Their distribution in the state seems to be regulated by the distribution of talus slides, and areas free of talus act as effective barriers to pikas. They are abundant throughout the Cascades but are absent from the Olympic Mountains although conditions there are well suited to them. Probably the lowlands of western Washington which, owing to moderate temperature and low relief, have little talus and exposed rock, serve as a barrier. The Columbian Plateau is also free of pikas. This may be due to the relative scarcity of talus as compared with mountainous areas, and the fact that much of the talus on the Plateau is composed of fragments of basalt too small to afford the shelter needed by pikas. The aridity of the Columbian Plateau may contribute to the absence of pikas, although this seems unlikely in view of the fact that they occur on arid lands in Nevada and elsewhere.
Altitudinally, pikas range from 300 feet, in Clark County, to 6,000 feet on Mt. Rainier, Pierce County, and on Round Top Mountain, Pend Oreille County. They occur from the arid subdivision of the Transition Life-zone, at Milk Creek, Kittitas County, to the upper edge of the Hudsonian Life-zone, at Glacier Basin, Mt. Rainier. Generally speaking, they are mammals of the mountains.
Common enemies of the pikas are the weasel (Mustela frenata), marten (Martes caurina), and hawks of several species. Pikas are active by day, especially in the early morning. Their call note is a short "eek!" which carries a long distance. This squeaking note is often heard throughout the night when rain threatens their drying hay.
Fig. 126. Distribution of the pika in Washington. A. Ochotona princeps brunnescens. B. Ochotona princeps fenisex. C. Ochotona princeps cuppes.
Vegetation used as food, either for immediate consumption or for winter use, includes almost all grasses, vines, shrubs, and trees available near the pika's home. The subalpine lupines are especially favored. Even such a thorny growth as the devil's club (Oplopanax horridum) is eaten. Heather (Phyllodoce, Cassiope) has not been found in any of the numerous hay piles examined, even when it is the commonest plant in the vicinity. Large bundles of plants are carried in the pika's mouth. The forefeet do not assist in transporting the load. If intended for immediate consumption, the plants are deposited on one of last year's hay piles and are eaten at leisure. The eating habits of the pika are rabbitlike. A large leaf is seized at the tip and drawn into the mouth with rapid chewing motions without assistance from the forefeet. Plants destined to become hay are carefully spread out and exposed to the sun. In cloudy or rainy weather the exposed plants are gathered and stored under large rocks, to be reëxposed for curing when the weather improves. Large hay piles often include more than fifty pounds of perfectly cured grasses, annuals, bushes and evergreens.