Baby, it’s cold outside

Winter has arrived in the Northeast and snow is in the forecast. While we are piling on the cozy layers and feasting on soup and hot chocolate, outside temperatures are dropping and food for wildlife is getting scarce. Animals across the region are tackling the season head-on and have some impressive strategies to cope with winter conditions.

Mostly brown snowshoe hare with white fur around face and ears sits in green grass. A piece of grass hangs out of its mouth.
White fur snowshoe hare sits in the snow
Left: Snowshoe hare during summer. Photo by Eric Bégin/Creative Commons | Right: Snowshoe hare during winter. Photo by Tim Rains/ NPS

In the winter, snowshoe hares completely transform, their fur changing from brown to white for better camouflage in the snow. They spend their time eating and hiding which helps to conserve energy for their encounters with predators, such as the lynx. Further south, the New England cottontail uses its brown coat to blend into thick underbrush, and uses snow as a ladder to reach higher shoots, seedlings and twigs.

Snapping turtle’s pointed snout, eyes and shell sit above the water with the rest the body submerged
Small tan frog with black horizontal stripe on its head blends into the leaf litter
Right: A snapping turtle peeks out of the water | Left: A wood frog camouflaged with leaf litter. USFWS

Have you ever wondered where amphibians and reptiles go in the winter? Most frogs, turtles, and snakes dramatically decrease their activity and enter a state of brumation, or dormancy, where their temperature drops and the heart rate slows down dramatically. Many turtles will bury themselves in mud at the bottom of a pond and absorb oxygen through their skin from the surrounding water. Wood frogs are even capable of freezing solid under leaves in forested areas. They are able to do this by filling their cells with a sugary substance that acts like antifreeze. The frog’s heartbeat stops and stays dormant all winter until they thaw again in spring!

Small white piping plover chick attempts to nestle under larger parent with white body and grey wings and head. Nest in sand
A piping plover and chick. Kaiti Titherington/USFWS

For many birds, the cold is just too much to bear. Like many of us in the winter, migrating birds including the piping plover, leave their homes on the chilly northern coast and take a vacation down south to the warmer shorelines and sandy beaches. Most piping plover are already in their vacation nests by mid-September and come back to work (and mate) by mid-April. Bird migrations vary in length, but some range from hundreds to thousands of miles each year.

Black bear sitting in a tree
An American black bear in a tree. Courtney Celley/USFWS

If long distance migration isn’t your thing, why not just sleep through winter like the American black bear? Bears aren’t true hibernators, but they can doze for up to 100 days at a time by slowing their metabolism and dropping their core temperature. Bears usually put on fifteen pounds a week during the fall to prepare for their long nap and stretch without food.

One bat flies through a shot of hundreds of bats huddled on the ceiling
As Andrew King took this shot, an Indiana bat flew beneath a large hibernating cluster of Indiana bats on the ceiling of Ray’s Cave, IN (taken pre-white nose syndrome.)

The Indiana bat, a true hibernator, accumulates layers of fat and spends months tucked away in its hibernaculum, like a cave or mine. Throughout winter, bats periodically rouse to move between hibernacula, before their heart rate and body temperature is dramatically lowered to conserve energy. Sadly, white-nose syndrome is plaguing bat hibernacula and causing populations of bats to plummet. Learn more about white-nose syndrome here.

A profile of a mottled brown bird as it sits in the snow.
A ruffed grouse in the snow by Head Harbor Lightstation/ Creative Commons

Ruffed grouse are non-migratory birds. They stick out the winters in their usual homes in a protected thicket or burrowed in the snow. In the late fall, feathers begin to grow on their legs to protect from the cold and help conserve body heat. Pectinations (fleshy comb-like projections along their toes) help them walk on soft snow, roost and burrow. Down feathers allow birds to trap air against their body to stay warm, and many birds will even cuddle together to keep warm.

Twenty or more swallows cuddle tightly together on one branch while it snows

We can learn a thing or two from wildlife this winter. Cuddling, sleeping, or vacationing through winter doesn’t sound half bad, especially if you’re not a fan of winter weather!

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