With winter approaching, many people are bracing for freezing temps and potential blizzards that can keep them indoors for days. But how do birds survive those same storms? The answer is threefold: Location, preparation, and adaptation.
Shelter in Place
When bad weather hits, birds generally seek shelter in microhabitats, such as inside a thick hedge, or on the downwind side of a tree—in this case, being petite has its advantages. Hunkering down in these spots can protect them from wind, rain, and even cold (it’s warmer closer to the ground). Birds that nest in cavities, including woodpeckers, bluebirds, and chickadees, can also hide out in their tree holes.
“I don’t know to what extent the birds actively pause and say, ‘it feels a couple of degrees warmer here’,” says Audubon’s field editor Kenn Kaufman, “but whether it’s instinctive or a conscious choice, they are definitely making moves to be in sheltered spots.”
Some birds will even wander several miles looking for adequate shelter and reliable food sources. Dense evergreens, spruces, or junipers provide better cover than the bare branches of a deciduous tree in winter. This helps keep the ground underneath pines snow-free, and gives birds a place to forage for food, too.
Beef Up in Advance
Fat birds have a better chance of surviving a storm. When birds sense changes in air pressure (a sign of brewing bad weather), they tend to forage more, or flock to feeders, says Kaufman. When the first significant snowstorm hit Ohio this month, the number of American Tree Sparrows in Kaufman’s yard soared from one lone bird to over 70 crowding around a feeder.
“You can see they are just out there feverishly stuffing their faces,” he says. “They can survive really cold temperatures as long as they get enough to eat.”
Evolution’s Got Their Backs
Birds have also evolved to withstand bad weather. Their lanky legs and little feet have what are called counter-current circulation. Birds have cold blood in their feet, which means very little heat is lost when they are standing on cold ground.
“The counter-current circulation is why you can see a bunch of Herring Gulls standing on the ice,” says Kaufman. “They aren’t jumping around and shivering because they are well adapted to that.”
Their feathers are the perfect insulation—they are basically natural down jackets. The down feathers underneath a bird’s contour feathers trap air, holding in the warmth from its body and preventing cold air from reaching its skin. Birds that winter in cold climates also don a thicker plumage in the winter, which they then molt in the fall and spring.
So, while we cozy up with our hot chocolates this weekend, there’s no need to worry about the birds—they are well-equipped to survive the ensuing tempest.