Two other marmots, very closely related to the hoary marmot, but differing from it in colour, live only on high portions of Vancouver Island and the Olympic Peninsula. The rockchuck, or yellow-bellied marmot, found from California, Texas and New Mexico to British Columbia and southwestern Alberta, is another close woodchuck relative. Where the woodchuck is brownish this somewhat smaller cousin tends to be yellowish. Scientists recognize as many as nine varieties or subspecies of woodchuck, mainly based on subtle differences in colour or skull characteristics. General appearance Among North American rodents, only beavers and porcupines are larger than the marmots.
Woodchucks are stocky little animals with a flattened head.
They commonly weigh 2-4 kg, and large ones may be heavier in the autumn. They measure 40-65 cm total length, including a short bushy tail about 15 cm long. Fur colour varies from place to place, and between individual animals. It ranges from yellowish to dark reddish brown, with an intermediate brown colour being the most common shade. The fur is usually grizzled in appearance, because of light coloured tips on the hairs.