What’s the big deal about groundhogs, February 2 and Punxsutawney Phil?
If you’ve seen the movie “Groundhog Day,” you know the starting place for the Bill Murray comedy: If a groundhog sees its shadow February 2, winter will last another 6 weeks. If he doesn’t see his shadow, spring will arrive earlier than expected.
But . . . are groundhogs reliable weather forecasters?
Yes! They’re natural weather forecasters, but that’s because they are true hibernators, according to Geoff Westerfield, a wildlife biologist with the Ohio Department of Natural Resources.
“They hibernate nearly the entire winter,” Westerfield says. “They won’t reemerge until the first few weeks of February when some signs of spring begin to show.”
True hibernation is different resting state than what skunks, raccoons, chipmunks and opossums do during cold periods to find shelter and sleep until weather changes.
True hibernation is how groundhogs survive cold weather, and the average hibernation period lasts about 5 months. But, before a groundhog enters hibernation, it built up its fat reserves by eating lots and lots of green plants, fruits and vegetables. The fat maintains its body when, during hibernation, its temperature drops by almost half, and its heart rate slows from 160 to 4 beats a minute.
Male groundhogs begin emerge from hibernation—often around February 2—when it’s time to mate or scout for mates. The groundhog’s reappearance can foretell weather conditions, and if the longer wait until spring might be necessary. Mating later could give its offspring the best chance of survival.
That fact, coinciding with nature-observant Dutch and German-speaking settlers marking Candlemas, a Christian holiday, on February 2, created the foundation for the first official Groundhog Day. It was observed in 1886 in Punxsutawney, Pennsylvania, where the local celebrity groundhog, one of many generations, is known as Phil.
Beyond the weather-predicting celebrations, groundhogs are interesting critters.
These marmots or rodents are close relatives of squirrels. Most of them weigh between 4 and 11 pounds, but some have been known to reach 30 pounds. Their young are called chucklings, and their life span is usually 2 to 3 years, although one groundhog in Ontario—Wiarton Willie—is known to have lived for 22 years.
These lowland inhabitants’ range reaches from the northeastern and central United States, as far south as Georgia, and into Canada and Alaska.
Groundhogs are also called as woodchucks, but they don’t eat wood. They can swim, climb trees, and some call them whistle pigs for their short, high-pitched warning whistles, or land-beavers who dig massive tunnel systems.
Farmers and homeowners consider them destructive pests not only for their voracious appetites for garden goodies, but for their impressive and destructive burrowing habits. Typically, they remove about 700 pounds of soil to make their burrows, an elaborate system of tunnels and rooms.
In central Ohio, one groundhog burrow was large enough to uncover the Ufferman Native American archaeological site by unearthing bones, pottery and stone tools.
The burrows they dig are used for sleeping, raising their young and for hibernating. Large burrows can have almost 50 feet of tunnels, with usually two to five entrances. The tunnels they dig can be five feet deep, which creates havoc with lawns and farmland, and can undermine building foundations.
But those pesky weather-predicting groundhogs have also made a unique contribution to the study of liver disease and hepatitis-B induced liver cancer in humans.
Researchers have found WHV-woodchuck hepatitis is similar to the human hepatitis B virus, which has led them to many discoveries in treating and preventing hepatitis B infection and the cancer it can cause.
Disease-free woodchucks have been the best available animal to study viral hepatitis in humans; the only other animal model is the chimpanzee, an endangered species.
– Resources: Ohio Department of Natural Resources, National Wildlife Federation, Cornell University Chronicle