Bird in Flight, Strong but Light

The feathers of a bird are, for their weight, among the strongest structures in the world. The bones of this Magnificent Frigatebird weigh less than its feathers! To further reduce weight while maintaining strength, many bird bones are fused. In addition, the pectoral and pelvic girdles and ribs are joined to make a rigid box that supports those long wings, just as the wings support the bird.

BirdNote^®
Bird in Flight, Strong but Light
Written by Dennis Paulson

This is BirdNote.

[Glaucous-winged Gull calls]

Look at that gull drifting across the sky. It seems to move through the air without effort. How does it stay aloft and fly so easily?

Natural adaptations have given it a strong yet lightweight body. And, for their weight, its feathers are among the strongest structures in the world. But aren’t a bird’s bones, like ours, heavy? Let’s take a closer look.

[Scream of a Red-tailed Hawk]

That Red-tailed Hawk circling overhead has hollow bones strengthened by struts — light but strong. The bones of frigatebirds, masters of the air, weigh less than their feathers! To further reduce weight while maintaining essential strength, many bird bones are fused. For example, a bird’s hand and fingers are made up of only six bones. In addition, the ribs of a bird are joined to other bones to make a rigid box that supports those long wings, just as the wings support the bird. And finally, the bird just wouldn’t fly that well, if not for the streamlining provided by its sleek feather coat.

With its body thus supremely adapted for the air, the Arctic Tern — one of the “super stars” of migration — can travel across thousands of miles of open ocean each year in effortless flight.

[Arctic Tern calls]

Learn more about birds, when you visit BirdNote.org. I’m Mary McCann.

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Bird audio provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Glaucous-winged Gull recorded by G.M. Bell. Red-tailed Hawk recorded L.J. Peyton. Arctic Tern recorded by G.A. Keller. BirdNote’s theme music was composed and played by Nancy Rumbel and John Kessler.
© 2013 Tune In to Nature.org September 2013 / 2017 / 2020 / 2022 / June 2025
Narrator: Mary McCann

ID# flight-04b-2020-9-14 flight-04b

References:
http://www.birds.cornell.edu/AllAboutBirds/studying/feathers/