Chicks are born between July and August on the ice floe, but do not have waterproof feathers until December
WWF
Several colonies of emperor penguins have again seen their chicks perish in 2023 due to the record melting of their Antarctic sea ice, linked to global warming, according to a study published Thursday.
The record decline in sea ice in 2023 contributed to the second worst year of chick mortality since observations began in 2018, according to the British Antarctic Survey observatory’s census.
This new finding follows the “catastrophic reproductive failure” in 2022 and threatens to reduce the population in the long term, Peter Fretwell, author of the study, told AFP.
These birds, popularized by the success of the film “The March of the Emperor” in 2005, reproduce on the ice floe, formed by freezing salt water from the ocean, and the chicks hatch during the southern winter, between the end of July and mid-August. They are raised until they develop waterproof feathers, usually in December, before the summer melt. But if the ice melts too soon under their little paws, they risk drowning and freezing.
They move to survive
Fourteen of 66 penguin colonies, each capable of hatching hundreds or even thousands of chicks per year, were affected by early melting in 2023, according to the study published in the “Journal of Antarctic Science.” This results in “high, if not total, mortality levels,” Mr Fretwell said.
However, 2023 “wasn’t as bad as we feared,” he said. Nineteen colonies were affected in 2022, a record. Several colonies, including those that saw their broods decimated the previous year, moved in search of better ice.
This encouraging sign of adaptation, however, is only a “temporary solution”, warned Mr Fretwell, because “there are only a limited number of places they can go”. For the researcher, it is up to humanity to adapt by reducing greenhouse gas emissions which contribute to the melting of the Antarctic ice floes, which until recently seemed spared the effects of global warming.
The sea ice has decreased by 30%
In 2022 and 2023, the minimum area of the sea ice, at the peak of the austral summer, fell below two million square kilometers, for the first time since satellite records began. That is a drop of around 30% compared to the 1981-2010 average.
Emperor penguins, aka Aptenodytes forsterihave around 250,000 breeding pairs, all in Antarctica, according to a 2020 study. If carbon emissions remain at current levels, their population is expected to decrease by 99% by the end of the century, the study warns.
(afp)
