for National Geographic News
How did the penguin cross the Equator? The question has vexed biologists ever since a Humboldt penguin, native to South America, was found off the coast of Alaska in 2002.
Now they have a likely answer: The flightless bird hitched a ride on a fishing boat.
"Penguins are kind of cute. People like them, and they're pretty easy to pick up," said Dee Boersma, a conservation biologist at the University of Washington in Seattle.
Boersma and graduate student Amy Van Buren looked at a series of possibilities for the out-of-place seabird and concluded the boat ride is the best explanation.
The penguin was likely hauled aboard in a fishing net and kept as a crew pet, the scientists suggest.
They speculate that other penguins spotted in North American waters, although very rare, may also have traveled by fishing boat.
A study on the Humboldt penguin's trek is published this month in the Wilson Journal of Ornithology.
Process of Elimination
With the exception of a population in the Galápagos Islands just a smidge north of the Equator, all 17 species of penguins are found exclusively in the Southern Hemisphere (see a penguins photo gallery).
So how did the Humboldt penguin get to Alaska?
A 5,000-mile (8,000-kilometer) swim from its home in coastal Peru is unlikely because it would have to survive a large area of warm, tropical water that doesn't have much food.
"That would be tough for a penguin to do," Boersma said.
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