Hundreds of emperor penguins in western Antarctica misplaced their chicks final yr, largely attributable to receding sea ice, satellite tv for pc knowledge counsel.
Over the past two years, sea ice has reached file lows round a lot of Antarctica (SN: 7/5/23). However whereas satellite tv for pc photos in 2022, geographer Peter Fretwell observed that ice in a single space was melting particularly early within the yr. He and his colleagues needed to measure the affect of this ice loss — within the Bellingshausen Sea off western Antarctica — on emperor penguins (Aptenodytes forsteri) within the area.
So the researchers checked out satellite tv for pc photos of colonies to find out the destiny of the breeding season (SN: 8/4/20). Of the 5 colonies noticed, 4 most likely misplaced all their chicks, the crew studies August 23 in Communications Earth & Surroundings.
Emperor penguins depend on secure sea ice all through their breeding season, which lasts from April to January. When an egg hatches, the new child chick should fledge, dropping its downy feathers to achieve its mackintosh.
In 2022, sea ice broke up earlier than some colonies had been completed fledging. With out waterproof feathers, fledging birds had been unable to outlive, Fretwell says. Of the kids from the ten,000 or so breeding pairs within the area, “we take into consideration 850 of the chicks survived,” says Fretwell, of the British Antarctic Survey in Cambridge, England.
Penguin colonies can recuperate from a single failed breeding season, says Annie Schmidt, a seabird ecologist at Blue Level Conservation Science in Petaluma, Calif., who wasn’t concerned within the new examine. And the researchers checked out just a few emperor penguin colonies of the 62 all through Antarctica.
A few of these different colonies have additionally skilled dangerous breeding seasons these days. On Antarctica’s Brunt Ice Shelf, the world’s second-largest emperor penguin colony on the time had three years of breeding failure from 2016 to 2018 after storms broke up sea ice there, Fretwell and a colleague beforehand reported. Between breeding failure and mass emigration to a different web site, the colony all however disappeared.
Repeated, or extra widespread, failure may threaten colonies and, ultimately, emperor penguins as an entire.
The brand new examine, documenting breeding failure throughout a number of colonies directly, “is the primary commentary that’s according to the worst expectations of what may occur” because the Earth continues to heat, Schmidt says. “I’m involved — it’s not a very good signal.” Latest estimates predict that the altering local weather and melting sea ice may lower emperor penguin populations by greater than half by 2100.
Regardless of that probably grim outlook for emperor penguins, Fretwell nonetheless has hope. “If we are able to decelerate world warming … we are able to flip across the destiny of the emperor penguin,” he says. “However that window of alternative is getting smaller, so we actually should act now.”
