The new year is an ideal time for Antarctic birds such as the south polar skua, Antarctic petrel, and snow petrel to build nests and lay eggs.
Researchers did not find a single skua nest on Svarthamaren, one of the areas where the birds raise their young, between December 2021 and January 2022.
Similarly, the number of Antarctic petrel and snow petrel nests has nearly vanished.
Climate change has resulted in significantly higher snowfall and accumulation in these regions than in previous years.
According to a study published on March 13 in the journal Current Biology, these unusually strong snowstorms have hampered the birds' ability to breed.
Entire Populations Of Antarctic Seabirds Fail To Breed
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They understand that when there is a storm, some chicks and eggs will be lost, and breeding success will be lower, according to Sebastien Descamps, first author of the study and researcher at the Norwegian Polar Institute.
"But we're talking about tens of thousands, if not hundreds of thousands, of birds here, and none of them reproduced during these storms; having zero breeding success is extremely unusual," he added as per ScienceDaily.
Svarthamaren and its neighboring Jutulsessen are home to two of the world's largest Antarctic petrel colonies, as well as important nesting grounds for snow petrels and south polar skua.
From 1985 to 2020, the colony in Svarthamaren had between 20,000 and 200,000 Antarctic petrel nests, around 2,000 snow petrel nests, and over 100 skua nests per year.
There were only three breeding Antarctic petrels, a few breeding snow petrels, and no skua nests in the 2021-2022 season. Similarly, there were no Antarctic petrel nests in Jutulsessen during the summer of 2021 to 2022, despite previous years showing tens of thousands of active nests.
"We're not talking about a single isolated colony here; we're talking about colonies spread out over hundreds of kilometers," Descamps says.
As a result of these stormy conditions affecting a really large portion of land, the breeding success of a large portion of the Antarctic petrel population was impacted.
Because these birds lay their eggs on bare ground, the ground becomes inaccessible with enough snow, making chick-raising impossible. Storms also have a thermoregulatory cost: the birds must use their available strength to shelter, keep warm, and conserve energy.
According to Descamps, there were no obvious signs of climate warming in Antarctica until recently. However, in recent years, new studies and extreme weather events have begun to change the way we think about climate change in Antarctica.
Descamps hopes that the model used to predict storm severity can be improved over time to be more accurate. "When it comes to storm severity, both wind and snow accumulation are important," he says.
There aren't many places where we can get accurate snow measurements, and they play an important role in explaining bird breeding success.
Adélie Penguin Numbers Decline Due To 'Fast Ice' Off Australia Coast
A significant decline in the population of Adélie penguins off the east Antarctic coast has alarmed scientists worldwide, as per Wion News.
The Australian Antarctic Division's monitoring revealed a 43% drop in the number of birds that breed across 52 islands near the Mawson research station over a decade.
This is reportedly in contrast to other Adélie penguin populations in east Antarctica, where numbers have been stable or increasing.
It also contradicts models that predicted a continued increase in Adélie populations.
From 2010 to 2020, seabird ecologists surveyed the islands along a 100-kilometer stretch of coastline.
The number of occupied nests decreased from 176,622 to 99,946, representing a loss of approximately 77,000 nests or 154,000 breeding birds.
Research published in Global Change Biology said that the decline in Adélie populations came about during a period of the simultaneous increase in "fast ice". It refers to ice that is attached to land but covers seawater.
The researchers estimate that in a good breeding season, the population had 80,000 fewer fledglings than at its peak in the early 2000s.
According to the study, an increase in the frequency of extensive summer ice throughout the study period resulted in poor breeding conditions and, as the population declined, an overall reduction in chick productivity.
Although there has been an overall decline in fast ice in Antarctica, scientists have observed regional variability, with declines detected in some areas and increases in others.
