A satellite mapping study has shown twice as many emperor penguins live in Antarctica than was previously thought.
Using very high resolution images, British Antarctic Survey researchers counted 595,000 birds, almost double the previous estimates of between 270,000 - 350,000.
They studied 44 colonies around the coast of Antarctica, seven of which were previously unknown.
The findings are reported in the Public Library of Science online journal.
The black-and-white plumage of the colonies is clearly visible on the ice in the satellite images.
This is the first comprehensive census of a species taken from space, said researcher Peter Fretwell.
The technology can be adopted for other studies, he said.