How Black Feathers Keep Ravens Cool

Surprisingly, lighter plumage isn't necessarily better in hotter climates.

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Transcript 

This is BirdNote.

Above a desert landscape, a raven soars, sleek black feathers against a vast blue sky.

The desert seems an unlikely choice for this all-black bird. But ravens thrive even in the hot, arid Southwest, where common sense suggests that light-colored feathers would be a better adaptation to the scorching sun.

But as it turns out, a raven's black plumage works quite well in the desert. Black feathers do conduct the sun鈥檚 warming rays, but they concentrate that solar heat near the feathers鈥 surface. All it takes is a light breeze to move all that heat away from the raven鈥檚 dark feathers.

Light-colored feathers absorb some of the sun鈥檚 rays, too. But they also tend to trap the heat closer to the skin, where it鈥檚 harder for cooling breezes to reach. So in even a slight wind, the skin of a black-feathered bird stays cooler than the skin of a white-feathered one.

For BirdNote, I'm Ashley Ahearn.

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Credits: 

Producer: John Kessler

Executive Producer: Sallie Bodie

Editor: Ashley Ahearn

Associate Producer: Ellen Blackstone

Assistant Producer: Mark Bramhill

Narrator: Ashley Ahearn

Bird sounds provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Common Raven call [132161] recorded by Gerrit Vyn. 鈥淗ouston In Two Seconds (Soundtrack Version)鈥 by Ry Cooder, from 鈥淧aris Texas Original Motion Picture Soundtrack鈥 2001

Warner Bros. Records Inc and WEA International Inc.

BirdNote鈥檚 theme was composed and played by Nancy Rumbel and John Kessler.

漏 2019 BirdNote   December 2014/2019

ID#  CORA-08-2014-12-15   CORA-08b