Antarctic emperor penguins stay on the same sea ice for months as they breed, during which time they produce large quantities of excrement(排泄物). Scientists at the British Antarctic Survey were looking at satellite images of their bases when they discovered that they could see the large brown stains of penguin guano(グアノ、鳥糞石)from space, and this gave them an idea: they could use the satellite images to pinpoint other colonies of emperor penguins. Overall, they found 38 colonies in this manner. Weather conditions in Antarctica are often forbidding(人を寄せ付けない), so this unusual technique will help scientists monitor the emperor penguin population from a distance.