Marten, a tree-climbing mammal of North America, Europe, and Asia. Martens are 24 to 40 inches (60 cm to 1 m) long, including a bushy 8- to 15-inch (20- to 38-cm) tail. The marten is a slender animal with short legs. The fur, brownish in color, is dense and silky and is highly prized for coats and wraps. The toes have long, sharp claws and, in some species, are covered with dense, stiff hair. The marten hunts at night for small rodents and birds. It also feeds on eggs, berries, nuts, and carrion. A litter of one to four young is born in April in a den.

The American pine marten, or American sable, and the fisher are found from Alaska to Newfoundland and south to California and New England. The American pine marten is yellowish-brown with dark brown legs and tail. The head is pale gray, and there is a pale buff patch on the throat and breast. The fisher is dark brownish-black with white-tipped outer hairs. Both species, once hunted to near-extinction for their pelts, are protected by law in many states.

The European pine marten ranges from western Europe to Siberia and south to Italy. It is chestnut to grayish brown with a light yellow patch on the chest. The stone, or beech, marten is found in rocky, open areas from Denmark and Spain to the Himalayas. It is grayish-brown to dark brown with a yellowish-white neck. The sable, or Russian sable, is found in mountainous areas in northern Europe, Central Asia, and Korea. The fur is pale grayish-brown or blackish-brown.

Martens belong to the family Mustelidae. The American pine marten is Martes americana; fisher, M. pennanti; European pine marten, M. martes; stone marten, M. foina; sable, M. zibellina.