How Alaska's winter birds adapt to the cold

This time of year, many of us like to sit back with a warm cup of tea and watch the birds that come to our feeders. Chickadees, nuthatches, woodpeckers and occasionally redpolls and pine grosbeaks partake of the free food. But what about the other birds that stay in Alaska through our long, often cold winters? The ones that don't visit bird feeders, like golden-crowned kinglets, American dippers or northern goshawks?

The diminutive golden-crowned kinglet stays in Alaska and can survive temperatures below -40 degrees Fahrenheit. Kinglets forage in mixed coniferous and deciduous forests throughout the year for the adults and eggs of spiders, mites and insects. To maximize foraging during the winter, they are active until dark. Once the sun falls, kinglets that spend the winter together will huddle near the trunks of spruce trees to keep one another warm until morning. You won't find them sleeping in the same place every night because they are on the move to find food during the day.

The American dipper also survives cold temperatures, including frigid water. These medium-sized songbirds have many physiological adaptations that enable them to forage in freezing water for aquatic insects, larvae, small fish and invertebrates. Dippers have more feathers than other songbirds and extra down for insulation. In addition to the thickness of their feathers, they have a lot of them - feathers even cover their eyelids. Dippers also have water-resistant feathers and can keep their body temperature a toasty 103 Fahrenheit even when the air temperature is below -30.

The northern goshawk is another bird that can survive Alaska's long and cold winters. The goshawk is substantially larger than the kinglet and dipper. Their greater mass and size help them to stay warm. If they get cold, they seek shelter near the trunk of a tree and cover their legs and feet with their thick feathers. Goshawks prefer to live in mature mixed forests where they hunt ptarmigans, squirrels, snowshoe hares, corvids and grouse. Goshawks are so elusive that one is more likely to spot a small flock of kinglets or a dipper foraging in a stream than find a goshawk perched in a cottonwood.

When you retreat to the warmth of your home after being outside in the cold, think of these hearty birds who survive the long, dark winter.

Bird Treatment and Learning Center remains open all winter. While we see fewer patients than in the summer, we are still here to care for the birds of winter.

If you're looking for an enjoyable and educational outdoor activity this winter, join the Audubon Christmas Bird Count. This annual will take place from Dec. 14, 2022 through Jan. 5, 2023. Get more information here: http://www.audubon.org/conservation/join-christmas-bird-count.

Lisa Pajot is an ornithologist and Bird TLC volunteer.

 
 
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