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Discolorations in the white infinity: penguins in the newly discovered colony at Verleger Point
Photo: Maxar Technologies 2023 /Bas / PA Media / dpa
Not only do they look majestic, they are also called that: Emperor penguins are probably the most impressive inhabitants of Antarctica.
Admittedly, they are also the only vertebrates that can survive permanently in the Antarctic ice sheet.
But that doesn't diminish the fascination they emanate - quite the opposite.
Exactly how many emperor penguins there are can hardly be said with any seriousness because of their isolated homeland.
According to estimates, about half a million adult animals plus offspring are likely to defy the extreme conditions of the southern continent.
The World Conservation Union (IUCN) classifies the largest of all penguin species as near endangered.
Over the years, population estimates have become more and more accurate - because researchers can now use satellite images for this.
The breeding colonies are usually on the sea ice or not too far inland.
As a reminder for all those who have not seen the Oscar-winning documentary »Journey of the Penguins« or have lost sight of it: The female emperor penguins lay one egg per year, which is incubated by the males.
There is no nest, the animals balance the egg on their feet in the extreme cold.
If they drop it, the hatchling in the egg is threatened with immediate death at temperatures as low as -60 degrees Celsius.
During the breeding period, the females hunt in the ocean for food for themselves and the young - fish, squid, krill.
After they have returned to the breeding colony, the males go to the sea, after which they swap again.
Telltale discoloration
The expanses of Antarctica are white and seemingly endless – except in the vicinity of these colonies.
Because there the ice turns brown for obvious reasons.
What the animals take in with their beaks has to come out again at some point.
And anyone looking specifically for such discolorations from space may be able to track down previously unknown colonies.
Recently, a group led by Peter Fretwell from the British Antarctic Survey succeeded: At 74° 42' south latitude, 136° 11' west longitude, the group found Verleger Point in West Antarctic Marie Byrd Land - which is named after a US captain – a site where about 500 emperor penguins live.
"This is an exciting discovery," Fretwell told the Guardian.
"But like many of the recently discovered specimens, this colony is small and located in a region that has been severely affected by recent sea ice loss."
First, Fertwell and his people looked for brown areas on the free images from the European Earth observation mission "Sentinel-2".
Once identified, these regions were analyzed in more detail using images from Maxar's commercial satellite, WorldView-3, which has a much higher resolution.
In this way, the experts were able to unequivocally prove the colony at Verleger Point.
Even individual animals were visible on the image.
To protect themselves against the cold, the penguins stand very close together in so-called huddles.
By slowly mixing the group, animals are sometimes further out and thus more exposed to the frost - and sometimes in the cuddly warm interior of the group.
But the problem of the emperor penguins is not the cold, they are familiar with that, but the warming caused by us humans.
This could ensure that – if heating continues as it has been up to now – 80 percent of the breeding colonies will have disappeared by the end of the century.
Most emperor penguins would never see a human in their lifetime, says researcher Fretwell, "but what we're doing on the other side of the world is slowly killing them."
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