Feb. 2 is Groundhog Day, when that famous Pennsylvania woodchuck, Punxsutawney Phil, emerges temporarily from his underground hibernaculum to let us know how much longer we must endure the winter weather.
According to legend, if it’s sunny and Phil sees his shadow when he comes out of his burrow, there will be six more weeks of winter. If however, it’s a cloudy day, and the mammalian prognosticator does not see his shadow, spring will begin early.
Woodchucks hibernate from late fall to early spring, but they do wake up and come out of their burrows periodically, said Tom French, retired assistant director of MassWildlife’s Natural Heritage and Endangered Species Program.
“On a sunny winter day they may come out,” said French. “They awaken and reposition themselves depending on the cold, then go back to sleep.”
When woodchucks hibernate, their body temperatures drop from 99 degrees to 40 degrees, and their heart rate decreases from 100 beats per minute to just 4 beats per minute, according to Mass Audubon’s “About Woodchucks” web page.
Woodchucks, also known as groundhogs, are actually “medium-sized, ground-dwelling squirrels,” according to MassWildlife’s “Learn about woodchucks” webpage.
Woodchucks are a type of rodent known as marmots, members of the squirrel family Sciuridae, which also includes tree squirrels, flying squirrels, and chipmunks, French explained. Woodchucks are found throughout Massachusetts and much of the eastern United States, across southern Canada, and into Alaska.
According to an article in Scientific American, the name woodchuck is believed to have been derived from the Algonquin Native American word for these animals, wuchak.
Adult woodchucks range from 17 to 32 inches in length, with 4- to 10-inch-long tails, according to MassWildlife. The weight of adult woodchucks can vary widely throughout the year, from about 5 pounds in early spring when they emerge from hibernation, to 14 pounds in the fall after they’ve put on weight in preparation for their winter sleep.
Woodchucks typically have reddish-brown fur with longer guard hairs that are gray with yellow tips, said MassWildlife. They also have brown or black tails, legs, and feet, and a black face.
Woodchucks have short, powerful legs and short ears, said MassWildlife, and dig burrows that may be up to 50 feet long. Their burrows can be as deep as 6 feet and typically have two, but sometimes several entrances, according to the National Wildlife Federation’s woodchuck fact sheet.
In addition to hibernation, woodchucks use their burrows as places to sleep, avoid predators, and raise their young, according to the New Hampshire Public Broadcasting woodchuck page. Woodchuck burrows have multiple chambers, one of which they use exclusively as a bathroom.
French said woodchucks often dig two burrows — a summer burrow, usually near a field where they feed on plants, and a winter burrow in the woods.
Surprisingly, woodchucks sometimes climb trees, like their squirrel relatives. French said there’s generally two reasons: to escape from predators, and to eat fruit such as mulberries and apples.
French said woodchucks also like to eat succulent vegetation such as clover, alfalfa, and buds on shrubs, and occasionally gnaw on tree bark. He said they’ll also eat vegetables, much to the consternation of gardeners.
Like all rodents, woodchucks have enlarged upper and lower incisor teeth in the front of their mouths.The incisors grow continuously and must be worn down by rubbing against each other when feeding or the teeth could grow to a length that injures or impairs the animal, according to MassWildlife.
To avoid or reduce damage and make your property less attractive to woodchucks, consider fencing, as well as closing off structures where woodchucks might like to burrow, such as underneath sheds, MassWildlife advised.
French said people also can try blocking woodchuck burrow entrances with rocks to try to encourage the animal to move on. If you are experiencing problems with woodchucks or have questions, contact your nearest MassWildlife office.
As far as what eats woodchucks, French said the list of predators includes foxes, coyotes, and bobcats. He also said large birds of prey, like red-tailed hawks, can take young woodchucks, which are about the size of a big guinea pig.
When woodchucks are surprised by a potential predator, they usually make a loud whistle-like chirping noise and run for their burrow, French explained. The noise is an alarm call that may serve to warn other woodchucks of approaching danger.
But when woodchucks are cornered, they can be tough fighters, said French. He said he once saw a bobcat try to attack a woodchuck in a field in Vermont, but the woodchuck fought back and managed to stave off the hungry predator.
“The woodchuck was originally down on all four feet grazing,” said French. “The bobcat rushed in but was seen by the woodchuck at the last moment. The woodchuck reared up and met the bobcat’s rush head-on. In what I presume was a move to avoid being bitten, the bobcat jumped straight up about 3 feet, and immediately moved about 4 feet away from the woodchuck which was still standing up tall on its haunches. The bobcat slowly circled the woodchuck with the woodchuck pivoting in the middle of the circle to keep facing the bobcat. During this time the woodchuck kept its front feet raised like a boxer in a defensive posture.”
French said the bobcat sat down for a bit, then eventually gave up and walked away.
Another hazard for woodchucks is being hit by cars, said French, as they like to feed on vegetation along roadsides and sometimes wander into the road.
Woodchucks mate in early spring shortly after emerging from hibernation and produce one litter per year in April or May, French said. Four or five young is typical, and they disperse from the den in August or September. On average, woodchucks live about three to four years in the wild.
Surprisingly, woodchucks sometimes carry rabies.
“Of all the rodents, woodchucks are the only one that comes down with rabies on a fairly regular basis,” said French. “It’s regular, but uncommon. My guess is there may be about two to five cases a year of woodchucks with rabies [in Massachusetts].”
French said woodchucks have a very unique musky smell that emanates from scent glands located around the anus.
“If you were to blindfold me and put a woodchuck in front of me, I’d know what it was right away,” said French.
Don Lyman is a biologist, freelance science journalist, and hospital pharmacist who lives north of Boston. Send your questions about nature and wildlife in the suburbs to email@example.com.