Antarctic shearwaters returned to the ocean last year rather than breeding in storms
AGAMI Photo Agency
Last year, extreme storms in Antarctica disrupted the breeding of tens of thousands of seabirds. If climate change caused similar events in the future, the decline in numbers could accelerate.
Sébastien Descamps of the Norwegian Polar Institute and his colleagues monitor three species of seabirds in Queen Maud Land, which covers one-fifth of Antarctica.
Birds such as Antarctic shearwaters, snow petrels and monitor lizards breed once a year during the Antarctic summer, laying eggs in late November and early December. Shearwater he lays one egg, while skua he tends to lay two, and newly hatched hatchlings are ready to fly between February and March.
However, due to a particularly severe storm between December 2021 and January 2022, the three species were essentially non-breeding in this part of Antarctica that summer. “Colony more than 500 kilometers away was affected,” he says Descamps. “The storm prevented breeding altogether, except for a few snow petrels that may have been breeding in storm-protected cavities.”
Tens of thousands of nests are typically found in this corner of the continent, says Descamps. His team estimates seabird populations by counting nests in 200 small plots and extrapolating the results to larger areas.
Strong winds make it harder to keep warm and hatch eggs, so blizzards probably keep birds away, says Decamps.
“At some point, long-lived species like seabirds prefer to abandon their eggs and return to the ocean to feed and gain energy, thus increasing their chances of survival,” he says.
“These long-lived seabirds have many opportunities for successful breeding throughout their lives, and the long-term effects of this particular event, which are astonishing to witness, are likely to wane,” said the New Yorker. “It will take years and more monitoring to know for sure,” says Heather Lynch of Stony Brook University.
Decamps agrees, but Antarctic shearwaters have been declining in Queen Maudland for 20 years, and more frequent or severe storms like these could accelerate population declines. , which is what climate models predict,” he says.
Thankfully, bird numbers breeding in these colonies appear to have returned to normal during the current Antarctic summer, he says.
topic:
