To a great many large rodents, burrowing ground squirrels common to our region, every day is Groundhog Day.
To humans who tend calendars with designated dates, however, Tuesday, Feb. 2, is Groundhog Day.
In the cult favorite movie “Groundhog Day,” Bill Murray’s character Phil gets caught in a time loop and wakes up every day, always the same day, in a Punxsutawney, Pennsylvania, bed and breakfast. Yet, a real, wild groundhog wakes up in a hole in the ground — if it wakes up at all.
And if you are hibernating in a dark, damp groundhog den, I am fairly sure that one day would be pretty much like any other.
Groundhog hibernation, or rather the emergence from it, is the focus of the special day on the calendar. Based on folklore, the day is alleged to be the time when a groundhog first awakens from his winter slumber. He is supposed to come to the surface, and if he sees his shadow, he is frightened back underground, foretelling six more weeks of winter.
If the sleepy-eyed rodent fails to observe his shadow — if it is too cloudy, one must assume — he is confident and free to remain topside. In that case, the experience is supposed to foretell an early spring. I suppose it can start right then.
It is all a crock of old wives’/husbands’ tales, of course, but it is something that people traditionally have enjoyed fooling with for generations.
The basis of our Groundhog Day is supposed to be when our native marmots first awake to check on the approach of spring. Of course, Feb. 2 is not necessarily when it happens, and that is not exactly what is going on, either.
Our groundhog is a stout rodent of about 20-22 inches long with a short, scruffy tail and is a grizzled brown color. Eating an herbivore diet that is heavy on succulent greens, he stuffs his face spring through early fall to attain a good layer of fat, pushing his weight up to about 15 pounds.
The groundhog — or woodchuck, if you prefer — runs short on food when freezing temperatures ensue, so it must hibernate and live on stored fat until spring restocks its natural pantry.
The accumulated calories from summer gorging would not be enough to last the tubby rodent through winter, so it must stretch the fat reserves by letting off the throttle, slowing down its body functions. That is the reality of true hibernation.
The deep sleeping groundhog’s heart and respiration rate drop dramatically. So does its body temperature, settling down to as little as 38 degrees during freezing weather. The critter is barely alive.
Biologists say a combination of longer days — increasing length of daylight — and occasional mild weather spells somehow allow the subterranean snoozing rodents to sense that winter is wearing thin. Consequently, groundhogs may arouse from sleep a time or two and come to the surface briefly before returning to their dens and re-entering hibernation.
At this latitude, it is typically late February to March before the earth pigs arouse from hibernation to stay. But there is one flitter of activity that might account for the folklore that we know as Groundhog Day.
Early February is known to trigger awakenings of male groundhogs that reactivate long enough to scout for the coming breeding season. An adult male may shake off hibernation and rev up its bodily functions, leaving its den to go topside. This brief foray allows him to find and explore the sleeping chambers of neighboring female groundhogs.
Wildlife scientists once thought that early-rising males bred females in their sleep state. However, further study determined that the males just studied the local population of sleeping females. Then when the boy rodents came out of hibernation to stay, they could beat a trail to the right places to find mates who also are coming back up to running speed.
(Maybe during the scouting rounds they can determine the best-looking females or the ones that are “their type.”)
If there are any local groundhogs emerging from their dens hereabouts on Feb. 2, chances are it will be boy ’chucks gathering intelligence on the ladies with whom they intend to procreate a few or several days later when it is closer to spring.
But the ones that emerge, then return to hibernation are not doing so because they were startled by the sight of their shadows. It would be more likely to keep from starving to death.
With little to no green food available, the winter-waking hours for a groundhog burns its candle at both ends. Rising from hibernation kicks up body functions and accelerates the draw on a woodchuck’s fat reserves.
A groundhog can’t stand too much of that before new spring food sources are available. A groundhog that is flabby-bellied and overstuffed as it enters its den in the fall may crawl out at the real beginning of spring as about half the same critter. It may lose half of its body weight by burning through stored fat during hibernation.
Actually, shedding significant fat as we sleep sounds like a great option. But if it has to be several weeks of near-death snooze in a cold dirt chamber three or four feet underground, I’m out.
Steve Vantreese, a freelance outdoors writer, can be contacted at firstname.lastname@example.org.