About us: We own the Wild Birds Unlimited nature shop in East Lansing, Michigan,
a store that provides a wide variety of supplies to help you enjoy the birdwatching hobby.

This blog was created to answer frequently asked questions & to share nature stories and photographs.
To contribute, email me at bloubird@gmail.com.

Wednesday, October 29, 2008

Nature up close: Why don't birds' feet freeze?


Birds actually use several tricks to keep their legs from freezing. First they can stand on one leg and pull the other up under their feathers when one leg starts getting too cold. And if it gets really cold, they can squat to cover both legs with breast feathers. If you see a bird doing this, they may be getting uncomfortably cold legs.

Also birds’ feet are mostly bone and tendons, so unlike mammals, they have a limited supply of nerves, blood vessels or muscles to freeze. Their feet are also covered with scales which isn’t a living tissue and less susceptible to freezing.

Finally, birds don’t have sweat glands in their skin to produce any moisture to freeze. Heat and moisture are accumulated in sacs, transferred to the lungs and eliminated through the mouth. No moisture escaping through their feet is also the reason they don’t stick to metal perches in the winter.