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Winter Bird Facts from The Birds of North America Online

Body Heat
Pygmy Nuthatch by Michael Woodruff	To save energy in winter, Pygmy Nuthatches roost together in holes. As many as 100 nuthatches may crowd into a hole, roosting in stacks of squares, oblongs, triangles, diamonds, or wedges. A bird at the bottom of the stack may save six times more energy than a bird alone at the top.

Fishing Holes
Although Snowy Owls prefer to eat lemmings, they sometimes resort to catching fish. John James Audubon observed a Snowy Owl that was fishing by lying belly down beside a water hole.	Snowy Owl by Mike Blom

Sleeping in Snow
Common Redpoll by Nick Saunders	Sometimes a Common Redpoll drops from a tree into the snow, then burrows in the snow, making a tunnel 27-40 cm long. The tunnel ends in a chamber 6-11 cm below the snow. The redpoll breaks through the snow to depart. Some researchers have proposed that the birds roost in the chamber; other observers believe roosting does not occur there and that the function is still unexplained.

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For permission to reprint all or part of this article, please contact Laura Erickson, editor, Cornell Lab of Ornithology, 159 Sapsucker Woods Rd., Ithaca, NY, 14850. Phone: (607) 254-1114. email: lle24@cornell.edu