In 2009, scientists noticed some odd stains cropping up in satellite images of Antarctica's Princess Ragnhild Coast. Now, explorers have traveled there -- the first humans to visit the 9,000-odd emperor penguin kingdom.
(International Polar Foundation)
Emperor penguin colonies are not easy to find: Their breeding grounds are remote, icy expanses, that are unobservable at distances greater than just a few kilometers due to the curvature of the Earth.
So scientists who want to monitor how these birds are faring in an unstable environment have had to come up with inventive ways of spotting them. One effective option: Penguin guano stains, as viewed from space.
In 2009, researchers published a paper identifying 10 new penguin colony locations based on satellite images of "faecal staining." "We can't see actual penguins on the satellite maps because the resolution isn't good enough. 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," Peter T. Fretwell, one of the paper's authors, told the Guardian at the time. In addition to the 10 new colonies, they were also able to confirm or revise the locations of 26 previously known colonies as well.
Global Ecology and Biogeography