Migration isn’t for everyone. For birds that skip the trip south each fall, staying warm and energized is key to surviving freezing temperatures and snowy weather. Fortunately, thanks to evolution, birds have developed numerous adaptations and strategies to persevere amid the harsh conditions. Here’s a look at some of the wintertime tactics you might observe out your window or birding in the field.
Donning Layers
Bird feathers are remarkable for many reasons, but their ability to repel water keeps birds dry in addition to providing warmth. Underneath, a base layer of fine, downy feathers traps body heat while keeping frigid air out. Birds in colder climates may also put on a heavier coat of plumage.
Fluffing Up
A puffed-up Northern Cardinal is a familiar sight when the mercury plummets, but how exactly does that help keep them warm? When birds fluff up, they create hundreds of air pockets between their feathers that trap heat, maximizing their natural insulation.
Hunkering Down
Birds: They’re just like us! When a winter wind starts whipping, the best thing to do is seek shelter from its sharp bite. For small birds like titmice and juncos, the denser the tree or shrub, the better. Tree crooks, cavities, and manmade structures are also popular places of refuge for birds of all sizes.
Huddling Together
What’s better than one bird body to stay warm? As many as space allows. If you spot a row or cluster of fluffy birds during the winter, they are combining forces to share heat and stay as toasty as possible. Bunches of bluebirds and sparrows, specifically, are a typical winter sight.
Adding Ounces
During winter, many species increase insulation and build up energy stores by eating more. In fact, for birds like chickadees and finches, fat can account for more than 10 percent of their winter body weight. This excess energy comes in handy if food is scant or the birds have to shiver the whole night through to keep warm—one of their more energy-intensive survival behaviors.
Caching In
In fall, it’s typical to see chickadees, nuthatches, woodpeckers, and other species return to feeders over and over. With each trip, the birds are carrying away seeds or peanuts to hide, or cache, for later when resources are scarce. A single chickadee can store up to 80,000 seeds—and remember where they all are.
Tucking Away
One place most birds don’t have feathers: their feet. Made mainly of bones and tendons with the little muscle, bird feet are built to withstand the cold. If needed, some species, especially larger birds that live on or around water, tuck one leg into their feathers for warmth while balancing on the other. Smaller birds often crouch for coverage.
