You might think you’re pretty clever with those chemical hand warmers and polyester layers to keep you warm and toasty, but the plants and animals around you have developed some pretty cool tricks of their own to cope with blustery winter weather.
Consider the wood frog. This critter can freeze solid in the winter. It has no heartbeat and doesn’t breathe, but when the weather warms up, it thaws out good as new. Most frogs don’t take things that far, but Ellanor C. Lawrence Park naturalist John Shafer says a lot of amphibians go through chemical and physiological changes to protect their cells during winter’s cold. Because there is moisture in cells, if that moisture freezes and expands in the winter, cell walls could pop. Certain amphibians have developed something that amounts to cellular antifreeze to keep that from happening.
It’s well-known that bears just don’t bother with winter at all and go into a period of hibernation. Of course, we don’t see many bears here in Fairfax County, but we do have one local hibernator — woodchucks. Don’t bother looking for them again until spring.
Some animals enter into a hibernation-like state known as brumation. They don’t really sleep like a hibernating bear, but their metabolisms slow way down. When the weather warms, you may see them up and around again, until the next cold front passes through. Chickadees can go through a brumation cycle every night, dropping their body temperatures way down after dark and warming them back up again so they can fly in the morning.
Shafer says gray squirrels are a prime example of animals that go into a state of torpor to shrug off the weather. He explains that in brumation, animals shut down some of their body systems. “Torpor is more like you have the flu and you stay in bed and sleep for three days,” says Shafer. “If you get a snowstorm, you don’t see the squirrels because they’re just like, eh, forget it. When it warms back up, they’ll come out and mess around.”
Some animals are just naturally good planners and never have to leave their homes to get a winter snack. Tony Bulmer, another of the Park Authority naturalists at Ellanor C. Lawrence Park, says that when chipmunks get hungry during the winter, they just eat from their pile of stored food. They can sleep on top of the stockpile and work their way down. “When it’s about done, it’s time to come out,” adds Bulmer.
Beavers like to plan ahead, too. Shafer says, “They store food, usually branches that they shove into the mud under the surface of the water. So, even if the whole pond freezes, they can come out of the lodge in their under-surface entrance, grab the food they’ve cached, just like our chipmunk, and then bring it back into the lodge to eat.”
You’re also less likely to see turtles popping up for air during the winter. Turtles can go down to the bottom of a pond and dissolve oxygen out of various parts of their skin during the whole winter. Bulmer says they can absorb or exchange just enough oxygen through the water to survive.
Water fowl have yet another coping mechanism. Some ducks and geese can shut certain veins off in their feet to prevent freezing. Bulmer says you might see them standing with one foot out on the ice.
When it comes to insects, you may not see adults flying around, but whatever eggs were laid in the fall are slowly developing into another stage. Those insect eggs can be just about anywhere, in the ground or in the trees.
Many people hope a cold winter will mean fewer of those annoying insects come spring, such as mosquitoes and ticks, but that’s not likely to happen around here. FCPA Ecologist Kristen Sinclair notes, “Everything has a point where it’s going to die, but it has to be really cold for a long time.” And when it comes to ticks, Sinclair says they’re “pretty darn active year round.”
In general, plants are more likely to react badly to temperature changes than animals. For instance, Bulmer says that with trees, “If we get five or six days that are 55 or warmer, it takes them out of the state of rest and they start producing buds. Then, if it freezes again, that can hurt the tree by injuring new buds.” Plants can’t put a bud under a bud, so those early buds can become a sort of dead spot on the plant.
One of the area’s earliest blooming plants is a native that uses chemistry to simply outsmart the weather. Shafer explains, “Skunk cabbage will actually heat up and melt itself a hole in the snow cover early in the spring so it can bloom and come up and get started.” Feel free to marvel at its cleverness, but you probably don’t want to take too big a sniff of this aptly-named plant.