Emperor penguins rocket toward an exit hole in the ice in the winning picture of the 2012 Veolia Environnement Wildlife Photographer of the Year competition, announced last Wednesday.

To get the shot—taken in Antarctica's Ross Sea for a new National Geographic article—photographer Paul Nicklen used polar survival skills he'd learned as a child among the Inuit on Canada's Baffin Island. Nicklen began by lowering himself through a hole in the ice and breathed through a snorkel while waiting for the penguins to return from foraging.

"They soared underwater like fighter jets in a dogfight," Nicklen told National Geographic's Luna Shyr. "Then they'd fly out, land, push down with their bill, and stand up, going back to that slow, waddling bird. It was a privilege to see." (Get more behind-the-scenes details.)

In a statement, competition judge David Doubilet said "Bubble-Jetting Penguins"—which also took top honors in the Underwater Worlds category—"draws us in for a glimpse of the emperor penguin's private world at the end of the Earth. I love this image, because it shows perfectly organized, infinite chaos. My eyes linger over it trying to absorb everything that's going on here." (See more emperor penguin pictures by Paul Nicklen.)

Now in its 48th year, the Wildlife Photographer of the Year competition is an "international showcase for the very best nature photography," according to the website for the contest, run by London's Natural History Museum and Wildlife magazine.

Each year an international jury of photographers judges tens of thousands of entries in 18 categories.

—Ker Than

Disclosure: Both National Geographic News and National Geographic magazine are parts of the National Geographic Society.

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