Winter has officially arrived in the Northern Hemisphere. With today’s winter solstice, the days will start to get a little longer, but the cold will persist. We humans generally deal with temperature drops by staying indoors, sleeping more, and dressing in layers. But what about other members of the animal kingdom? Here are some unique ways animals survive the winter cold.
Brumation Nation
To combat the winter cold, some reptiles and all amphibians brum. Brumation is basically a less intense form of hibernation. Bears and other mammals that hibernate spend much of their time sleeping. Instead, amphibians and misting reptiles go through a period of dormancy with small bursts of activity.
“During the winter, brumation is like taking a long nap, getting up when it’s a little warmer, going to the bathroom, drinking some water, and then going back to sleep,” says Karen McDonald, STEM program coordinator at the Smithsonian Environmental Research Center in Maryland. Popular science. “Hibernation means sleeping all winter and relying on your fat reserves.”
Reptiles and amphibians need to wake up to drink water so they don’t become dehydrated. They usually rise up for a refreshing sip on milder winter days. If they’re lucky, they’ll get a little more sunlight.
Frozen Frogs
When cold fronts descend on Florida, frozen iguanas will inevitably fall from trees. But for wood frogs that live in New England, the Mid-Atlantic and the Midwest, this cold is much more common. However, their solution is not brutal. Instead, they freeze solid.
For months, wood frogs burrow under the dead leaves of the forest floor, without breathing, heartbeat or brain activity. As soon as the weather starts to warm up, they will come back to life. According to the National Park Service, this strategy allows wood frogs to become active very early in the spring. The land thaws and warms more quickly than ice-covered lakes where other frogs bury themselves in the mud. This means that newly active wood frogs can mate and lay eggs in small ponds earlier than other frogs.
Take care of these feathers
Not all bird species survive the winter by flying south to warmer climates. Some, like cardinals, chickadees and blue jays, stay put. To survive the cold, they must take very good care of their feathers. Some species will have new feathers for winter. Other birds fluff their feathers to help trap pockets of air around their bodies and stay warm. Preening also helps some birds waterproof their feathers, by spreading oil from a gland near their tail to the rest of their body.
Birds will also find good places to crouch or huddle with other birds of the same species. Winter berries and some other plants will also produce fruit that can help sustain them until spring. A well-stocked bird feeder can also help, but just be sure to keep it clean.
Blue Christmas (crab)
The blue crabs that inhabit the Chesapeake Bay spend their winters in the deeper parts of the bay. There they bury themselves in the mud underwater and enter a dormant state.
“It’s not traditionally considered hibernation because unlike some mammals, crabs don’t undergo physiological changes that reduce their body temperature,” says Matt Ogburn, a senior scientist at the Smithsonian Environmental Research Center. Popular science. “Nevertheless, they remain largely inactive and their metabolism slows down.”
Blue crabs will stay like this until the water temperature reaches around 50 degrees Fahrenheit.
“As lonely as an oyster”
We’re not saying that oysters are lonely misers like Ebenezer Scrooge. These filters are actually very good for the planet. Oyster beds provide important storm barriers, and bivalves help keep the water clean. In a single day, an oyster can filter up to 50 gallons of water.
They obtain most of their food by filtering water through their bodies and scavenging for nutrients like algae and plankton. However, these food sources diminish in winter.
“Oysters feed frenziedly in the summer, when there is a lot of algae filtering the water,” Ogburn says. “This helps them store the glycogen that they burn to survive the winter.”
In winter, they will go dormant and survive on these sugar reserves, similar to those that reptiles and amphibians rely on during brumation.
Yes, turtles breathe through their butts
Turtles spend the winter underwater, where they breathe through their buttocks. Although it may seem a little unusual to us mammals, breathing through our buttocks is an important survival strategy.
“This allows turtles like snapping turtles and painted turtles to stay frozen under the ice while still breathing underwater,” says McDonald.
This process is called cloacal respiration, during which they exchange gases through the tissues lining their cloaca, the end of their digestive tract. This allows them to remain submerged underwater for longer periods of time.
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