David Ellis/USFWS • A common redpoll feasts on stiff goldenrod seed. These small finches can endure temperatures 100 degrees below freezing.

With the arrival of January, we can probably be assured of some cold weather. I’m not fond of the cold, but I can put on gloves and a thicker coat and I am good to go.

What about our feathered friends? How do birds cope when temperature plummet below freezing?

Birds actually employ a range of strategies and behaviors that keep them cozy even during the worst that winter can hurl at them.

Some birds avoid the necessity of coping with cold by migrating. All those tropical species that brighten the warmer seasons in the mountains of Southern Appalachia withdraw to warmer areas in Central and South America during the winter.

Those birds that elect not to put distance between themselves and cold temperatures must do something to stay warm. Feathers are one of a bird’s defining traits, and they can do a neat trick with their feathers to stay warm. You’ve probably seen them do this. They will fluff their feathers, trapping air between them to provide insulation. If you’ve ever noticed that some birds look “fatter” in extreme cold it’s likely because they have fluffed up to combat the cold.

Of course, feathers require good maintenance to help with the task of staying warm, and birds are diligent about such tasks. Preening feathers on a routine basis keeps them watertight and able to hold in heat. Some birds even grow extra feathers in autumn to prepare for cold temperatures. That’s similar to dogs or cats growing a denser coat of fur in anticipation of wintry temperatures.

Birds have different comfort levels when its comes to personal space, but many of the more sociable species will huddle together. You’ve probably seen nature documentaries of penguins in the Antarctic as they huddle together for weeks on end to endure the harsh conditions of the globe’s southernmost continent.

Larger species of birds, such as geese and grouse, eat more and gain weight, which is often achieved by the storage of body fat.

Other birds have also adopted the huddling strategy in a cozy cavity or nest box. My most vivid recollection of an observation of this strategy involved Eastern bluebirds. During a severe cold snap accompanied by snow and blustery winds, I watched multiple bluebirds enter one of my nesting boxes. I’m not sure how many entered the box, but it was likely about eight to 10 birds.

Necessity makes birds adaptable. The next day the aforementioned high winds took down the post that held the nest box. At dusk the bluebirds showed up again. They looked baffled to find the box had disappeared. Then I saw them fluttering into an old tire that I had used at the base of the pole to help anchor the box. Faced with oncoming darkness, they chose to huddle together inside the old tire.

Natural cavities in trees also provide cozy roosting spaces for birds. Chickadees and titmice, nuthatches and woodpeckers seek out such cavities ahead of time so they will always be ensured of a warm space during bouts of inclement weather.

The biological mechanism of torpor is one that’s probably familiar to fans of hummingbirds, but other small birds can also take steps to lower their body temperature. Chickadees and kinglets put this ability to good use. In these small birds, the adaptation being employed is known as controlled hypothermia. Chickadees can drop their body temperature by as much as 22 degrees below normal daytime body temperature.

Snakes and reptiles can enter a physical state called brumation, where they sleep more but still wake to eat, drink and enjoy the sun on warmer days, according to information on the Facebook page of the U.S. Fish and Wildlife Service. Since snakes are cold-blooded, they’re lethargic at these colder temperatures even when they’re on the move.

Hibernation, although a strategy widely used by mammals, is rare in birds. The common poorwill (a relative of whip-poor-will and chuck-will’s-widow – is the only bird known to go into torpor for extended periods that can range from weeks to months. On the southern edge of their range in the United States, poorwills spend much of the winter hibernating, usually concealed in rock piles.

There’s warmth in numbers. Crows, starlings, robins and other species will gather in communal roosts to use body warmth to stay warm overnight. Sometimes these roosts are quite large and can lead to conflict with nearby humans who may not want the noise and mess that comes with hosting a large flock of birds.

While warm socks and gloves protect human toes and fingers, birds don’t have to worry about frostbite. Quick circulation means that blood does not linger in their feet long enough to freeze. In addition, the legs and feet of birds are covered in scales. Like feathers, the scales provide excellent insulation.

Some birds will gather together in large stands of evergreens. I’ve observed house sparrows gathering in the holly trees outside the courthouse in downtown Erwin at dusk on cold evenings.

There are things we can do to help. Plant evergreen trees or construct a brush pile that will provide shelter from the elements, as well as a measure of safety from predators, for the birds that share our lawns and gardens.

Many people already feed birds. Try supplementing seeds with some food rich in fat. Birds, unlike us, will not be adversely affected by a high-fat diet. Their metabolism allows them to burn off the extra calories in an enviable amount of time. Some high-fat foods that birds will love include peanut butter and beef suet, as well as peanuts and other assorted nuts. While it’s relatively simple to render suet into a usable for for birds, most people cannot be blamed for turning to commercially made suet cakes. Many of these are also made even more appealing with a mix of peanuts or fruit into the suet cake. The extra calories derived from these foods will let birds better regulate their body temperature and tolerate the more frigid nights.

It’s also important to provide liquid water for birds. Outdoor heaters designed to fit into a birth bath can help prevent the water from freezing during cold snaps.

Birds will also appreciate a sunny spot. By basking in sunshine, they can also boost their internal temperature.

Some birds are just built for cold. For example, snowy owls have been observed in temperatures 80 degrees below zero. Species of redpolls, a type of finch, can endure temperatures 100 degrees below freezing.

Emperor penguins live and nest in some of the most inhospitable terrain on the planet. Those who have viewed the documentary film “March of the Penguins” will be familiar with the species. Their colonies on the ice in the Antarctic must endure temperatures than can plunge to -40 degrees Farenheit. They must also survive frigid winds that can reach 90 miles per hour.

Emperor penguins have several adaptation to help them survive such cold conditions, according to the World Wildlife Fund. These penguins have two layers of feathers, a reserve of fat and beaks and flippers that are proportionally smaller than those for other penguin species.

Lee Karney/USFWS • The common raven can live in a range of habitats, but these large and intelligent birds are especially adapted to cold.

The common raven is another bird that shrugs off cold and snow. They can survive and thrive in habitats as varied as Arctic tundra and scorching deserts. If temperatures drop below -4 degrees Farenheit, ravens can generate extra body heat.

All things considered, birds are simply better at coping with cold than we are.

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Bryan Stevens has written about birds since 1995. To ask a question, make a comment or share a bird sighting, email him at ahoodedwarbler@aol.com.