by Leah Cass
Groundhog day is rapidly approaching when famed groundhog Punxsutawney Phil will issue his prediction on the changing of the seasons. Legend says he will either see his shadow and retreat into his den, condemning us to six more weeks of Winter, or he will emerge shadowless, signaling an early Spring. The tradition evolved from what was originally a Pagan celebration of coming Spring. This celebration was later modified by Christianity, becoming a feast known as Candlemas. Some believed that a sunny Candlemas meant 40 more days of winter weather.
Candlemas spread throughout Europe and Germans added their own take on the legend, measuring the sunniness of the day based on if small animals like badgers could see their shadows. When German immigrants came to Pennsylvania, they continued the tradition, switching out badgers for groundhogs which are common throughout the northeastern United States. Since then, Punxsutawney Phil has issued his predictions with a success rate of about 50%—certainly not inspiring a lot of confidence in his skills as a weatherman. However, the tradition, and the groundhogs behind it, has continued to capture the hearts of Americans around the country.
But how much do you really know about these elusive little animals?
Groundhogs (Marmota monax), also commonly known as woodchucks, are one of fourteen species of marmots. They are true hibernators which means they eat as much as they can during the warm summer months before retreating into their dens to rest throughout winter. The male groundhogs awake from their slumber early to begin searching for the dens of female groundhogs and potential mates. That’s why every Groundhog Day celebration from Punxsutawney Phil to Staten Island Chuck features a male groundhog.
The males wake and emerge from their dens in February. They will then search their territory which is usually a two- to three-acre area, claimed by one male but often housing multiple females. When he comes to a female den, the male will enter and spend the night there, leaving the next morning. Generally, males will visit two or three female burrows during this time. However, mating does not occur until later in the season. Biologists have described these meetings as potentially being a chance to “get to know each other” so to speak and exchange biological information. After these “dates” the male groundhog returns to his own den and continues hibernation for an additional month. It isn’t until Spring when he reawakens and mates with the females he previously visited. Baby groundhogs are generally born in April following a 30-day gestation period.
Groundhogs construct impressive burrows that often reach around 20 feet in length, excluding side passages. These burrows include a “nest” area for hibernation and mating which is usually lined with dead leaves and grass. They also construct a separate latrine area, much like a bathroom. Burrows have a main entrance for coming and going and a secondary entrance that typically functions as a “spy hole” to keep watch for predators.
Groundhogs, especially babies, are preyed upon by foxes and coyotes as well as hawks and other birds of prey. Groundhogs themselves are omnivores and will eat a combination of plant materials such as grass, bark, and fruit as well as invertebrates like insects, snails, and grubs. They can grow to be about ten pounds. Groundhogs are mostly crepuscular meaning they are most active during dusk and dawn. However, it is possible to see one at any time during the day. The average lifespan in the wild is about three years, though they often live up to six. In captivity groundhogs have made it an impressive fourteen years.
Groundhogs are often considered a pest species by humans because they can destroy gardens by stealing food and potentially damaging underground structures with their burrows. However, they also offer many benefits to humans and other wildlife. By burrowing, groundhogs both turn and aerate the soil which helps with nutrient cycling. The burrows are often used by other animals such as skunks, foxes, opossums, and raccoons. Additionally, many of the invertebrates eaten by groundhogs are considered pests by humans, and we benefit from their help managing these species. Thanks groundhogs!