Animals Wildlife Secrets of the Groundhog Revealed By Melissa Breyer Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. our editorial process Melissa Breyer Updated February 01, 2019 CC BY 2.0. Wikimedia Commons Share Twitter Pinterest Email Animals Wildlife Pets Animal Rights Endangered Species Behold the mysterious groundhog. We know them as prognosticators of spring and muses for cult movies, but these furry creatures from the pantheon of giant rodents have other secrets to reveal. Here we tell all in 23 sentences. 1. The groundhog (Marmota monax) is one of 14 species of marmots and is closely related to squirrels: “They are giant ground squirrels is what they are,” says Richard Thorington, curator of mammals at the Smithsonian National Museum of Natural History. 2. While most marmots are gregarious and love company, groundhogs are loners; the "monax" in their name is Latin for "solitary." 3. Groundhogs go by several aliases, including woodchuck, whistle-pig, forest marmot, and land beaver. 4. A woodchuck can’t chuck wood – the name doesn’t have to do with wood, rather it is thought to have its roots in Native American language. 5. As “true hibernators,” groundhogs go into a dormant state and can reduce their body temperature to 41F degrees and slow their hearts to about five beats a minute. Shenandoah National Park/Flickr/CC BY 2.06. To survive winter during hibernation, they feast all summer on plants ... like your garden ... which is why groundhogs, cute as they may be, are not adored by all. 7. Along with vegetation, they also eat grubs, grasshoppers, insects, snails, other small animals and bird eggs. 8. They can reach 24 inches in length. 9. They weigh between 12 and 15 pounds. 10. They’re impressive builders; a groundhog’s burrow can extend up to 66 feet long, with multiple levels, exits, and rooms. They even have bathrooms. 11. And they can really dig: A single groundhog can move over 700 pounds of dirt when making a burrow. 12. Their dens are important for other animals too; red foxes, gray foxes, opossums, raccoons, and skunks often take up residence in homes built by groundhogs. S. M. Kriebel/Flickr/CC BY 2.013. Although they conform to their name by staying primarily on the ground, groundhogs are also decent swimmers and can climb trees! 14. Like other members of the rodent family Sciuridae, groundhogs have exceedingly dense cerebral bones and can survive blows to the skull that would likely be fatal to other mammals of the same size. 15. Unlike other sciurids, groundhogs have a curved spine, as do moles. 16. Mom groundhogs have one litter per year of two to six babes, which are called kits or pups. 17. Groundhogs are very clean, which may be one of the reasons they are resistant to the diseases that periodically decimate large numbers of wild animals. Wikimedia Commons/CC BY 2.018. When not feeding or burrowing, groundhogs will stand erect and be on the lookout; when sensing danger, they emit a high-pitched squeaky whistle. 19. They have great timing and know exactly when to wake up from their fall/winter slumber; if they miss the short mating window, babies born too early won’t have enough food, those born too late they won’t be able to gain enough weight for winter. 20. Artifacts found in a groundhog hole led to the discovery of an important archeological site in Pennsylvania. 21. Groundhog Day comes from the German Candlemas Day, but the original shadow-caster was a hedgehog; German settlers in Pennsylvania found groundhogs plentiful, and thus, it’s Groundhog Day not Hedgehog Day. 22. While Punxsutawney Phil is the nation's premiere rodent meteorologist, he's not the only one, consider these other shadow-casting contenders: General Beauregard Lee of Atlanta, Georgia; Sir Walter Wally of Raleigh, North Carolina; Jimmy of Sun Prairie, Wisconsin; Octorara Orphie of Quarryville, Pennsylvania; Staten Island Chuck from the Staten Island Zoo; Unadilla of Nebraska; Buckeye Chuck of Ohio; French Creek of West Virginia; and the Cajun Groundhog from Louisiana. 23. But even so, based on past weather data, not even Punxsutawney Phil can likely really forecast the weather: "There is no predictive skill for the groundhog during the most recent years of the analysis," according to a report released by the National Centers for Environmental Information in Asheville, N.C. ... since 1988, Phil was "right" 13 times and "wrong" 15 times ... but that won't keep us from rooting for a quick return to spring.