In so-called "granary trees," acorn woodpeckers drill remarkable pegboard-like patterns in which they store thousands upon thousands of acorns for food over the winter. And the Austral pygmy-owl, endemic to parts of Argentina and Chile, can be identified by its high-pitched toot. These are just a few of the incredible array of bird species represented by the top entries in this year's Audubon Photography Awards.
The Arctic Tern is not the only bird that spends its breeding season in the Arctic. Billions of birds belonging to nearly 200 speciesfrom small sparrows such as the Smith's Longspur to large waterfowl such as the Greater White-fronted Goosemake their way to the far north every spring to reproduce and then make the return flight south for the winter.