Emperor penguins are one of the Antarctic’s most iconic animals – but these majestic birds are on the pathway to extinction.
For the first time, satellite images have captured the penguins’ elusive moulting colonies, where they replace their feathers with new waterproof plumage.
Moulting is a particularly dangerous time for emperor penguins as they cannot enter the water to feed for several weeks while their new plumage regrows.
The dramatic images reveal how shrinking sea ice is forcing the birds into smaller, increasingly crowded groups.
If the weakened ice breaks up early, this could spell disaster for the thousands of unprepared birds still trying to replace their feathers.
Dr Peter Fretwell, lead author of the study, warned of the potentially ‘catastrophic’ consequences for the species.
‘[This] almost certainly brings the extinction horizon closer, maybe by several decades,’ he told the Daily Mail.
‘Although it will take more work and analysis to calculate exactly how much.’
For the first time, satellite images have captured the penguins’ elusive moulting colonies, where they replace their feathers with new waterproof plumage
These images show that penguins are being forced into larger, more crowded moulting colonies. This risks disaster if the sea ice breaks up before they can grow their new plumage
Each year, emperor penguins from the Ross Sea migrate as far as 620 miles (1,000 km) to Marie Byrd Land in search of stable sea ice to moult on.
‘A penguin’s feathers keep it waterproof and warm, and must be well oiled (using oil from a special gland at the base of the tail),’ the British Antarctic Survey explains.
‘Feathers become worn out and must be replaced every year.
‘During the three to four weeks of moulting, penguins come ashore.’
Until now, how and where these moulting colonies form has remained a mystery.
By chance, researchers analysing satellite images spotted some distinctive brown patches along the coastline of Marie Byrd Land.
Since the timing lined up with when emperors were supposed to moult, they realised that these patches must be penguin moulting colonies.
Before 2022, the team identified hundreds of groups of moulting penguins along the coast of Marie Byrd Land.
During their moult, emperor penguins cannot enter the water to feed for several weeks. If they are forced into the water prematurely, they risk death due to exhaustion and hypothermia
However, by 2022, that number was slashed to just 25, with penguins forced to clump together on the dwindling sea ice.
Dr Fretwell said: ‘It’s possible that huge numbers of penguins perished after entering the Southern Ocean before they had replaced their waterproof feathers.
‘If this has happened, the situation for emperors as a species is even worse than we thought.’
Between 2022 and 2024, Antarctic sea ice hit record lows as coverage in the study area fell from a 50-year average of 193,000 square miles (500,000 square km) to just 38,600 square miles (100,000 square km).
That left just 770 square miles (2,000 square km) of fast sea ice anchored to the coast to accommodate 40 per cent of the world’s emperor penguins.
According to the experts, this is particularly worrying because emperor penguins are so slow breeding.
Previous studies have shown that the species can live up to 20 years, but does not mate until the age of three or six.
Looking ahead, the researchers suggest the birds might start to look at new moulting sites.
Before 2022, there were more than 100 penguin colonies on the coast of Marie Byrd Land, West Antarctica. In 2025, there were just 25, as penguins either died in the breakup of sea ice or moved to other parts of the continent
Dr Fretwell explained: ‘Early evidence suggests that they will look around for better moulting sites.
‘We know that they are adaptable, at least in where they go, but other sites are rare and the sea ice is less stable, so there is inherent risk in choosing a new site.’
In the coming weeks, a separate study is expected to release an analysis of penguin populations in the Ross Sea.
This will answer the key question of exactly how many adult penguins have been killed by the breakup of sea ice during moulting.
Dr Fretwell says that Antarctic scientists are ‘waiting in trepidation’ for the news.
EMPEROR PENGUIN IS THE LARGEST SPECIES OF THE FLIGHTLESS BIRD
The Emperor penguin is the largest species of penguin, reaching heights of around four feet (1.2 meters) tall, and weighing between 49 pounds (22 kilograms) and 99 pounds (44 kilograms).
They are recognisable due to their distinctive black back and head, white breast and yellow patches on their necks.
The flightless birds inhabit the Antarctic, huddling together to keep warm in the icy climate, where temperatures reach as low as -90C.
Emperor penguins breed and raise their young almost exclusively on sea ice, with the females laying eggs before heading off to hunt for food, leaving the males to incubate the egg.
If there’s too little sea ice, it reduces the availability of breeding sites and prey for emperor penguins, but too much ice means longer hunting trips for adults, which means they can’t feed their chicks as frequently
After the chick is born, parents take turns foraging at sea and caring for the newborn within the colony.
The birds’ diet consists primarily of fish, but they will also eat crustaceans, such as krill, and cephalopods, such as squid. To facilitate hunting the penguins can remain underwater for up to 18 minutes, diving to a depth of 1,755 ft.
The relationship between Emperor penguins and sea ice is fragile.
If there’s too little sea ice, it reduces the availability of breeding sites and prey, but too much ice means longer hunting trips for adults, which means they can’t feed their chicks as frequently.
