The groundhog (Marmota monax), also called woodchuck or whistle pig, is one of 14 species of marmots, and the only one that occurs in the Mid-South. The other North American marmots are confined to nothern and western alpine or open forest regions. All marmots are burrowing, herbivorous rodents in the squirrel family (Sciuridae) which enter true hibernation in the late fall and emerge in late winter or very early spring. Our customary Groundhog Day on Feb. 2nd arose from observing this regular emergence of groundhogs early in the year. Though people are fond of predicting the weather based on whether or not the groundhog can see its shadow, the real reason groundhogs come out to look around probably has more to do with finding a mate and reproducing.
Groundhogs have prodigious appetites, needing to lay in lots of body fat to support them through the winter. Their penchant for raiding vegetable gardens brings them into frequent conflict with their human neighbors, as do their impressive underground burrows which can be 8-66 feet long, according to one study, and can render the ground above quite hazardous for livestock or farm equipment.
Read "9 things you didn't know about groundhogs" from National Geographic.