(Marmota monax) A thickset marmot of the north eastern United States and Canada. Also called ground hog. Live in lowland forests and meadows. Eat tender plants such as alfalfa and clover and are often considered pests. They dig tunnels up to 30 feet long and hibernate in burrows in winter. They are the groundhogs of Groundhog Day, though most remain underground long after February 2.