The Laboratory Woodchuck ( Marmota monax )

The Eastern woodchuck, Marmota monax , is in the family Sciuridae of the order Rodentia. Common names include groundhog, whistle-pig, and chuck. Natural distribution includes the Eastern and Midwestern United States, Southeastern Alaska, and Southern Canada. The woodchuck is a large, burrow- digging animal with a thickset body, short legs, long claws, broad flat head, almost no neck, small, round ears, and a short, hairy tail. Adults in captivity reach an average body size of 3–5 kg in males, and 2.5–5 kg in females. Colors vary from a grizzly gray-brown to reddish, with a darker head and black feet. Black as well as white (presumably albino) woodchucks have been reported. The fur consists of a soft dense undercoat and a longer, coarse upper fur.