Emperor penguins (Aptenodytes forsteri) on the sea ice close of the Brunt Ice Shelf.

A space-based sensor has detected new colonies of emperor penguins on Antarctic sea ice. Credit: Christopher Walton

Ecology

Satellites find penguins by following the poo

Images from space bolster the population count, but the birds remain vulnerable to climate change.

From their vantage point high above Antarctica, sharp-eyed satellites have spotted eight previously unknown colonies of emperor penguins. The discovery boosts emperor penguin numbers by 5–10%.

The iconic birds breed and raise their young on sea ice frozen to Antarctica’s shoreline. These habitats are threatened by climate change, so scientists have been working to get a complete census of emperor penguins (Aptenodytes forsteri) to assess how the bird’s populations might change.

Peter Fretwell and Philip Trathan at the British Antarctic Survey in Cambridge, UK, used the European Space Agency’s Sentinel-2 satellites to search for dark smudges of guano-stained ice. They identified eight newfound penguin colonies located around the rim of the continent; one was on sea ice frozen around icebergs grounded far offshore. Using the images, the authors also pinpointed three colonies that had been reported in the 1960s and 1980s but not confirmed since.

The findings bring the total number of emperor penguin colonies to 61. Many are in areas vulnerable to climate change.