How to Identify a Groundhog. Groundhogs, which are large rodents found throughout the eastern half of North America, take center stage every February, when the emergence of the animal dictates the coming of spring. The groundhog is a stout herbivore, sometimes reaching up to 30 lbs., and stretching out to nearly 3 feet long from nose to tail.
Identify a groundhog by its size. A groundhog looks similar to a common tree squirrel, but can grow much larger. An average groundhog measures 16 to 24 inches from nose to tail, weighing up to 10 lbs., but can grow much larger if natural predators, such as coyotes and wolves, are scarce.
Look at the fur. The coat of a groundhog appears to have "frosted tips," which are coarser and lighter than the dense grey hair of the animal's undercoat. In addition, the coat of the groundhog may appear to be banded vertically as you observe the body from head to tail.
Check out the claws. Groundhogs have powerful, curved claws that allow the animal to burrow into the ground quickly. The front legs of the groundhog are also short and muscular to accommodate burrowing.
Observe the tail. Groundhog tails are much shorter and more compact than the bushy tails of most tree squirrels. The tail of the groundhog is usually less than one-fourth of the total length of the animal.
Note the warning behavior. Like its cousin, the prairie dog, groundhogs often stand upright to observe their surroundings, constantly looking for predators. When a groundhog sees danger, it will whistle toother groundhogs as a warning.
Observe the head. A groundhog has an unusually dense skull, which allows the animal to be more aggressive when it comes to digging burrows. The animal easily can withstand a head blow that would kill most rodents the same size.
Identify a groundhog by its curved spine, which also differentiates it from tree squirrels. Its rounded spine allows the groundhog to adopt a better posture for digging and navigating through burrows.
While groundhogs have pleasant, almost charming demeanors, they can be aggressive in the wild. Be cautious whenever approaching a groundhog, and allow it room to escape to its burrow.