Groundhog day is coming up on February 2. The legend goes that if a groundhog emerges from its den and sees its shadow, six more weeks of winter are coming. If not, then Spring will arrive early. The legend has had different iterations over the hundreds of years of its existence. Early February traditionally marked the beginning of the growing season across parts of Europe. February 2, Candlemas day, marks the halfway point between the winter solstice and the spring equinox. The Candlemas celebration marked the anticipation of the planting of crops so a determination of a prolonged winter or an early spring was important. Emerging hibernators was a natural choice of an indicator that spring was coming. In England and France, a bear was the symbol of an emerging spring, while in Germany it was a badger. German immigrants to the United States in the 1800s substituted the lack of badgers in the Pennsylvania area with groundhogs and the tradition continued.
The average date of groundhogs emerging from hibernate in southeastern Pennsylvania occurs around February 4th according to Stam Zervanos, Emeritus Professor of Biology, Pennsylvania State University. This timing fits in well with the local legend. Unfortunately, the timing of the emergence of groundhogs as an indicator of weather is little more than a coincidence. The real reason groundhogs emerge, according to Zervanos, has more to do with Valentine’s Day. In preparation for mating season in March, groundhogs emerge in early February to essential “date” or more scientifically, “reestablish the bonds necessary for mating and ensures that mating can then proceed without delay in early March.” If “dating” in February and mating in March happens, then groundhog offspring will arrive in early April. This ensures the best chances of survival for the young groundhogs who need to be born not too early and not too late in order to take advantage of the start of food availability in May.
Wardle, H. N. (1919). Note on the Ground-Hog Myth and Its Origin. The Journal of American Folklore, 32(126), 521-522.
Candlemas/Groundhog Day. (n.d.). Retrieved from Candlemas/Groundhog Day. (n.d.). Retrieved from https://www.almanac.com/fact/candlemasgroundhog-day-its-no-accident-that-groundhog-holiday
Zervanos, S. (2015, February 2). Why do groundhogs emerge on February 2 if it’s not to predict the weather? Retrieved from https://theconversation.com/why-do-groundhogs-emerge-on-february-2-if-its-not-to-predict-the-weather-36376