How Feathers Insulate

How do birds stay warm when it's so cold?

This story comes to you through a partnership between Audubon and BirdNote, a show that airs daily on public radio stations nationwide.


Written by Frances Wood

Imagine this Canada Goose paddling along on a cold winter day. Can you guess how many feathers cover this goose? Hundreds? Thousands?

A single Canada Goose has between 20 and 25 thousand feathers. A smaller bird like a sparrow or wren might have 7 to 10 thousand. Those feathers are uniquely designed to help the bird fly, shed water, or display distinctive markings. A great many feathers are the short, fluffy kind, the down, whose purpose is to insulate the bird from the cold.

Birds survive in sub-zero weather by fluffing their feathers, creating layers of air and feathers. Just a fraction of an inch of this insulation can keep a bird’s body temperature at 104 degrees, even in freezing weather.

People learned years ago how well goose-down insulates and began stuffing comforters, sleeping bags, and clothing with it. More recently, we’ve developed artificial substitutes, but geese and other birds continue to get along just fine with the original material.

January is a good time to begin a new volunteer activity, and Audubon chapters can help you find your niche. After all, “nicher” in French means to nest. To learn about opportunities, begin with a visit to


Bird sounds provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Calls of the Canada Goose [3585] recorded by G.B. Renyard. Winter wind Nature SFX Essentials #02 recorded by Gordon Hempton of BirdNote’s theme music was composed and played by Nancy Rumbel and John Kessler. Producer: John Kessler. Executive Producer: Chris Peterson. © 2014 Tune In to    January 2014   Narrator: Michael Stein


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