Yellow-throated marten larger than other Old World martens; males measure in body length, while females measure . Males weigh , while females weigh . The anal glands sport two unusual protuberances, which can be used to secrete a strong smelling liquid for defensive purposes. The yellow-throated marten has relatively short fur which lacks the fluffiness of the pine marten, sable and beech marten. The winter fur differs from that of other martens by its relative shortness, its harshness and its luster. It is also not as dense, fluffy and compact as that of other martens. The hairs on the tail are short
American marten the larger fisher. The Newfoundland subspecies of this animal ("Martes americana atrata") is considered to be threatened. The Pacific Northwest subspecies, the Humboldt marten, is even more so, with only a few hundred individuals remaining. Compared to other carnivores, American marten population density is low for their body size. One review reports population densities ranging from 0.4 to 2.5 individuals/km. Population density may vary annually or seasonally. Low population densities have been associated with low abundance of prey species. Home range size of the American marten is extremely variable, with differences attributable to sex, year, geographic area, prey availability, cover