Douglas squirrel

John Muir described the Douglas squirrel, Tamiasciurus douglasii, as "by far the most interesting and influential of the California Sciuridæ". Adults are about 33 cm in length (including its tail, which is about 13 cm long), and weigh between 150 and 300 grams. Their appearance varies according to the season. In the summer, they are a grayish or almost greenish brown on their backs, and pale orange on the chest and belly, while legs and feet appear brown. In the winter, the coat is browner and the underside is grayer; also, the ears appear even tuftier than they do in summer. Like many squirrels, Douglas squirrels have a white eye ring. Mating can occur as early as February. Gestation is about four weeks, and the young (which are altricial) are weaned at about eight weeks of age. There may be up to six kits in a litter, though four is more usual. In the southern and lower parts of their range they produce two litters each year.