What the heck is a groundhog?

A Groundhog (Marmota monax)

Happy Groundhog Day, everyone! During this time of groundhog celebration, do you ever stop and wonder, "What in the world is a groundhog?"

We have all watched Punxsutawny Phil or Wiarton Willie emerge from his burrow to forecast the weather countless times, but where in the world did this tradition come from? And what is a groundhog in the first place?

Well, I am glad you asked, dear reader, for although these rotund rodents are national celebrities, most Groundhog Day revelers don't realize what a groundhog really is.

Groundhogs go by many names, other than "Phil" and "Willie" of course. Some call them whistle-pigs, land beavers, and, more commonly, woodchucks. But groundhogs do not have any immediate relations in the swine family (Suidae) and definitely aren't beavers. Rather, groundhogs are squirrels. Yes indeed, groundhogs (Marmota monax to be precise), and all other marmots for that matter, are the largest members of the squirrel family, Sciuridae.

An Olympic Marmot (Marmota olympus)

Here in the Northwest, we do not have groundhogs, but we have plenty of marmots, ground squirrels and gophers if you are searching for a woodchuck-related encounter.

What's the difference between these mammals, you ask?

Well, that depends on your definition of each critter.

Marmots are large Scuirids in the genus Marmota. In some regions, prairie dogs are also known as marmots, however these squirrels are in the genus Cynomys. Fun fact: the Olympic Marmot (Marmota olympus) is the only mammal uniquely endemic to Washington State.

A Mazama Pocket Gopher (Thomomys mazama)

Ground squirrels are a bit more difficult to define. In fact, recent phylogenetic revisions have split what was once a monogeneric clade (Spermophilus) into eight genera... In other words, nobody really agrees. And colloquial definitions vary as well. Typically, when one is referring to "ground squirrels," one could be referring to antelope squirrels (Ammospermophilus), typical ground squirrels (Urocitellus, Callospermophilus, and Ostospermophilus, all formerly in Spermophilus), prairie dogs (Cynomys), or even chipmunks (Tamias).

Gophers are equally difficult to define. Colloquially, gophers can include Scuirids, such as typical ground squirrels (as mentioned above) and prairie dogs, or it can include or members of the pocket gopher family, Geomyidae. The most common pocket gophers here in the Pacific Northwest are members of the genus Thomomys such as the Northern Pocket Gopher (T. talpoides) and the endemic Mazama Pocket Gopher (T. mazama).

A White-tailed Antelope Squirrel (Ammospermophilus leucurus)

Perhaps most confusing of all, is the fact that Groundhog Day has its origins with a different creature entirely - a badger. The tradition may have its roots in - yes, you guessed it - ancient Pagan celebrations of weather lore, where a badger or sacred bear would perform antics similar to those seen with today's Phil and Willie. Although the exact history of pre-American Groundhog Day is spotty, we know for sure that the event was first celebrated in the US in the 18th century by German-Americans in Pennsylvania. Today, celebrations occur throughout Canada and the United States, with the exception of Alaska where Marmot Day takes its place. Throughout North America however, it appears that groundhogs (and marmots for that matter) are equally bad at predicting meteorological events.

To learn more about Groundhog Day and its history check out this Wikipedia page. To learn more about "gophers" click here. Still curious about groundhogs and marmots? Click here!
And for those of you still intrigued by a rodent's weather-predicting capabilities, according to Punxsutawny Phil, we are set to have an early spring!
Happy Groundhog Day!

-Robert Niese
Education and Outreach Specialist

A California Ground Squirrel (Otospermophilus beecheyi)

A Least Chipmunk (Tamias minimus)

A Black-tailed Prairie Dog (Cynomys ludovicianus)