Canis lupus.—The dark wolf (fuscus) of western Washington is probably a coastal race. The race that may have occurred in northeastern Washington probably was an invader from the Rocky Mountain Fauna, and the race that possibly occurred in southeastern Washington would be assumed to have long been a resident of the area.
Felis concolor.—The cougar of western Washington is a coastal race, probably developed while isolated in southwestern Washington and western Oregon. The cougar of northeastern Washington probably entered the state with other Rocky Mountain species, early in the Recent. The cougar of the Blue Mountains of southeastern Washington has probably long been resident there.
Lynx rufus.—The bobcat of western Washington seems to be a coastal race that was isolated in either southwestern Washington or western Oregon by Vashon ice. It has since extended its range into southern British Columbia. The bobcat of eastern Washington seems to be a member of the Great Basin Fauna that has spread to some forested areas on the periphery of the more arid life-zones.
Lynx canadensis.—The lynx is an element of a northern fauna that was probably forced southward into the Cascades and Rocky Mountains. Its range was probably more extensive, as is indicated by the scattered records of its occurrence in Oregon ([Bailey], 1936:271).
Marmota monax.—The woodchuck invaded northeastern Washington in the early Recent with the Rocky Mountain Fauna.
Marmota flaviventris.—The yellow-bellied marmot is a typical member of the faunas of the Great Basin and the southern Rocky Mountains. It has doubtless entered southeastern Washington from eastern Oregon at an early time. In northeastern Washington, west of the Columbia River, it occupies alpine habitat, but it does not occur farther east, where Marmota monax is found, or in the Cascades where Marmota caligata lives.
The yellow-bellied marmots are great wanderers, and commonly are found in scattered outcrops far out on the Columbian Plateau. There is even one record for western Washington, near Bellingham, Whatcom County. This individual must have crossed some low pass in the Cascades from the area about Lake Chelan. There are records of eastern Washington birds occurring in this same area, so it seems likely that the marmot was a natural stray and not an animal that escaped from captivity.
Marmota caligata.—The absence of the hoary marmot from the Cascades of Oregon, and the presence there of Marmota flaviventris, indicates that the species did not occur in the southern Cascades of Washington during Vashon Time. Presumably the hoary marmot is a member of the fauna of the northern Rocky Mountains and entered the Cascades of Washington in the Recent, after which it spread widely and rapidly owing to lack of competition with any established species of marmot.
Marmota olympus.—This species has probably lived in the Olympic Mountains since pre-Vashon Time.
Citellus washingtoni.—This ground squirrel has probably lived on the Columbian Plateau since before Wisconsin Time.