Description

This stout-bodied rodent weighs up to 13 pounds and has a body length of up to about 20 inches and a short, bushy tail up to 18 cm (7 inches) long. Thick fur on the upper parts ranges in colour through various shades of brown; the feet are darker, and the underparts are buff. Melanistic (nearly black) and albino individuals sometimes occur in some populations. Found from the eastern and central United States northward across Canada and into Alaska, they most commonly live along forest edges abutting meadows, open fields, roads, and streams, but they are occasionally also encountered in dense forests. The groundhog is solitary except in the spring.

Groundhogs have four incisors, shaped like chisels, two upper and two lower of which the upper two continue to grow at the rate of 1/16 of an inch every week! To keep the growth of the front teeth in check the groundhogs have to constantly chew or gnaw on leaves or grass. They also spend a good amount of time nibbling at trees or roots so that the teeth can be worn down. The groundhog defends itself from predators by using its two large incisors and claws.

Behavior

Both male and female groundhogs tend to occupy the same territories year after year. For females, there is very little overlap between home ranges except for the late spring and early summer, as females try to expand their territories. During this time, their ranges may overlap by as much as 10 percent. Males have non-overlapping territories as well, though any male territory coincides with 1 to 3 mature females' territories.

Interactions between female groups — even when those groups are shared by the same adult male — are rare and aggressive. Even though daddy groundhog doesn't live at home, from the breeding season through the first month of the infants' lives, he visits each of his female groups every day.

Groundhogs are active during the day. In summer they commonly feed in the early morning and the late afternoon, spending the rest of the day sleeping or basking in the sun. In late summer they begin to put on weight in preparation for the move to their winter dens, often located in wooded areas. They hibernate from October through March. While hibernating, a groundhog's body temperature drops from 99°F to 40°F, and its heartbeat drops from 100 beats per minute to 4 beats per minute!

Groundhogs can swim in order to evade predators or survey their territory for potential food sources. Their net legs make it easy to swim, and the paddles allow you to sail the water. Its tail is mighty and can also be used as a defensive device – either by hitting an enemy or slamming it into the water to create an intense splash. Groundhogs can swim at about 2 miles per hour.