"We can't see actual penguins on the satellite maps because the resolution isn't good enough," said mapping expert Peter Fretwell. "But during the breeding season the birds stay at a colony for eight months. The ice gets pretty dirty and it's the guano stains that we can see."
The method helped scientists identify 38 penguin colonies -- of those, 10 were new. Of previously known colonies, six had re-located and six were not found.
Link -via Simply Left Behind
(image credit: Flickr user Carles-FlashOnTheBlog)
Previously at Neatorama: Penguin Poop.
Tracking them is a good idea... regards, sovi.
Sounds like tax code logic to me.