Emperor penguins die as ice melts to new lows: study April 26, 2024

Ana Cunha-Busch
Apr 25, 2024
2 min read

The British Antarctic Survey study found that record sea ice levels in 2023 contributed to the second-worst year for emperor penguin chick mortality since observations began in 2018 © SARAH DAWALIBI / AFP/File

By AFP - Agence France Presse

Emperor penguins die as ice melts to new lows: study

Paris (AFP) - Colonies of emperor penguin chicks were decimated last year as global warming eroded their icy homes, according to a study published Thursday, despite the birds' attempts to adapt to the shrinking landscape.

The British Antarctic Survey study found that record sea ice levels in 2023 contributed to the second-worst year for emperor penguin chick mortality since observations began in 2018.

This follows a "catastrophic breeding failure" in 2022, signaling long-term implications for the population, study author Peter Fretwell told AFP.

Emperor penguins breed on sea ice shelves, with chicks born in winter, between late July and mid-August.

The chicks are raised until they develop waterproof feathers, usually in December, before the summer melts.

But if the ice melts too soon, the chicks run the risk of drowning and freezing.

Fourteen of the 66 penguin colonies, which can produce hundreds to thousands of chicks a year, were affected by the early loss of sea ice in 2023, according to the study published in the Journal of Antarctic Science.

The result is "high, if not total, levels of mortality", said Fretwell.

However, 2023 "wasn't as bad as we feared," he said.

A record 19 colonies were affected the previous year.

On the move

The study also found that several colonies, especially those that were devastated the previous year, moved in search of better conditions for icebergs, ice shelves, or more stable sea ice.

Although these changes offer a hopeful sign that the birds can adapt to the changing environment, Fretwell warned that it is a "temporary solution".

"Penguins are limited in the amount of adaptations they can make. There are a limited number of places they can go," he said.

Instead, Fretwell said that humans need to adapt by reducing the greenhouse gas emissions that warm the planet and are contributing to the melting ice, to mitigate the main threat facing the species.

Both 2022 and 2023 were the first years in which the area of sea ice fell below two million square kilometers (770,000 square miles) since satellite records began.

This marks a drop of around 30% compared to the average from 1981 to 2010.

There are around a quarter of a million breeding pairs of emperor penguins, all in Antarctica, according to a 2020 study.

"If there are several bad years, this will start to reduce the population over time," said Fretwell.

The study noted that if greenhouse gas emissions continue at current levels, the penguin population is expected to decline by 99% by the end of the century.