Putorius vison energumenos Bangs, Proc. Boston Soc. Nat. Hist., 27:5, March, 1896.
Mustela vison energumenos [Miller], U. S. Nat. Mus. Bull., 79:101, December 31, 1912.
Type.—Obtained at Sumas, British Columbia, by A. C. Brooks on September 23, 1895; type in Museum of Comparative Zoölogy.
Measurements.—A male from Seattle, King County, measures: total length 540; length of tail 180; hind foot 66; weight 1 pound, 15 ounces.
Distribution.—Throughout the state save for the Columbian Plateau; recorded from Neah Bay ([Taylor] and [Shaw], 1929: 11) in the northwest, Ilwaco (M.V.Z.) in the southwest, Metaline (W.W.D.) in the northeast, and the Blue Mountains ([Dice], 1919: 12) in the southeast.
Fig. 58. Distribution of the mink, Mustela vison energumenos, in Washington.
Description.—Because of the value and lasting popularity of its fur, the mink is known to all. Few persons, however, recognize the animal in the wild. The mink possesses the long, slim body and short, rather stout legs of a weasel but has a more bushy tail. The mink is larger than the weasel. Large males weigh up to 3 pounds; females 1-1/2 pounds. Males measure about 2 feet in length, of which the tail comprises eight inches. Females measure about 20 inches and have tails 7 inches long. The color is rich, dark reddish or chocolate brown. The underparts are slightly paler than the back. There are usually small white markings on the chin, chest or other part of the ventral surface. These markings sometimes take the form of narrow white lines.
The mink ranges from the Atlantic to the Pacific and from Alaska south to Florida, New Mexico and central California. It is active throughout the year and is principally, though not exclusively, nocturnal. [McMurry] (1940: 47) records three mink seen at 3:30 p. m. on August 8, 1939, at Packwood Lake, Lewis County, one of which was carrying a garter snake two feet in length. This mustelid is semiaquatic, living along rivers, streams, lakes and salt water and spends most of its time along the shore, on muddy or sandy beaches. In this respect it resembles the raccoon. Whereas the raccoon spends a part of its time on the land, the mink spends a corresponding amount of its time in the water. It is an excellent swimmer, able to overtake and capture fish in the water.