Winter weather has begun at Frost Valley and we’re thrilled to see an icy crust on Lake Cole and snow collecting on the ground! This season comes with challenges of course, but at Frost Valley we believe winter is a fun and meaningful time for outdoor exploration and family bonding. We want to help our community make the most out of this winter, and to do that we’ll learn some tips from a special Catskill critter with a sweet winter survival skill: the wood frog!
In the warmer months we’re used to seeing wood frogs hop around but as the temperature drops they seem to disappear. After a few months it feels as if they might be gone forever, but each spring they return. So where do they go and how do they survive? We’ll have to take a quick trip underground to see how our wood frogs spend the winter and we’ll taste a homemade popsicle while we’re there!
Wood frogs are cold-blooded, so they begin the winter by looking for a warm insulated hiding spot down below the frozen soil where they can tuck themselves in for a long hibernation. Once the wood frogs are nestled in their hiding places, their breathing and metabolism slow dramatically and their heart rate drops to just a few beats per minute. In this sedentary state, they can survive with barely any food or air while their body temperatures drop low.
As the winter matures and frost creeps deeper into the ground their warm hiding spot begins to freeze. Ice tickles threateningly at their skin but the frogs have a secret weapon! Just minutes before ice crystallizes within them, their livers kick into overdrive and fill their blood with sugar. The frogs slowly freeze solid, their hearts still, they stop breathing, and they seem to have passed away. They lie lifelessly for weeks, or even months; but once the snow melts our frogs defrost and suddenly come back to life again—all thanks to sugar!
What makes sugar a powerful secret weapon? Let’s find out! Try filling a cup with water and another cup with fruit juice, then place these cups in your freezer. Check on the cups every twenty minutes and stir them to see if they have begun to form ice. Which do you think will freeze first, and what do you think the difference in time might mean for our frogs? After the experiment is over, the frozen fruit juice makes a delicious popsicle!
You might have noticed that the fruit juice cup did not freeze as quickly as the water cup. That is because the dissolved sugar in the water gets in the way of the water molecules that stick together to form ice crystals. While ice forms in between the cells of our wood frogs, the inside of the sugar-filled cells do not freeze as solidly, which saves the lives of our frozen friends.
Though it’s cold and the days are short, the winter is special. At Frost Valley, we believe in stepping out of our comfort zones to embrace all that the snow and ice have to offer—with activities like broomball, snow tubing, cross country skiing, snow shoeing, and ice fishing. After that we like to defrost by the fireplace with friends and family, and take a moment to relish the magic of the winter time: the fun memories, the family bonding, and the warm feeling that lingers deep inside. We hope you’ll join us for winter family camp, a winter weekend, or a school trip to make the most of this winter season, and to help us wish our wood frog friends a sweet winter!
U.S. Department of the Interior. (n.d.). Biological miracle. National Parks Service. Retrieved December 9, 2021, from https://www.nps.gov/gaar/learn/nature/wood-frog-page-2.htm.
Scientific American. (1997, November 24). How do frogs survive winter? why don’t they freeze to death? Scientific American. Retrieved December 9, 2021, from https://www.scientificamerican.com/article/how-do-frogs-survive-wint/.
Wood frog. National Wildlife Federation. (n.d.). Retrieved December 9, 2021, from https://www.nwf.org/educational-resources/wildlife-guide/amphibians/wood-frog.
Special thanks to Tyler Katz for their frog photography!