WASHINGTON - Scientists looking for lost penguins stumbled upon an effective method: Follow their poop from space.

Researchers in remote Antarctica have been unable to figure out just where colonies of emperor penguins live and if their population is in peril.

It's harder still because emperor penguins, featured in the film `March of the Penguins,' breed on sea ice, which scientists say will shrink significantly in the future because of global warming.

Because the large penguins stay on the same ice for months, their poop stains make them stand out from space.

Scientists at the British Antarctic Survey found this out by accident when they were looking at satellite images of their bases.

A reddish-brown streak on the colourless ice was right where they knew a colony was, said survey mapping scientist Peter Fretwell.