A recent study reveals that four out of five emperor penguin colonies in Antarctica’s Bellingshausen Sea region likely lost their chicks last year due to disappearing sea ice beneath their breeding grounds. The loss of sea ice occurred before the penguin chicks had developed waterproof adult feathers and learned to swim. This widespread failure across multiple colonies in the region is unprecedented. Scientists are uncertain if this is an isolated incident or a consistent trend with potential repercussions for the species.
Antarctic sea ice levels are projected to reach record lows in 2023, causing concern among scientists and leading to speculation about the stability of Antarctic sea ice. Dr. Norman Ratcliffe, a seabird ecologist with the British Antarctic Survey and one of the study’s authors, suggests that events like the early loss of sea ice and subsequent breeding failures may become more common in the future, potentially indicating a significant change in Antarctica.
Due to the remote location of the Bellingshausen Sea region, researchers relied on satellite images to track the penguin colonies by observing their guano, which leaves a distinct reddish-brown trace on the snow and ice. Emperor penguins rely on sea ice attached to the Antarctic continent to lay eggs and raise their young until they can swim and fend for themselves.
Despite climate change, Antarctic sea ice remained stable or even increased until around 2016. However, since then, it has been declining. In 2022, the extent of sea ice around Antarctica reached a record low, with the Bellingshausen Sea being the most affected region. As sea ice continues to melt, emperor penguins may struggle to find suitable breeding grounds, potentially leading to population decline.
Currently, there are approximately 600,000 emperor penguins across 61 known colonies. In 2022, the United States listed the species as threatened under the Endangered Species Act, promoting international cooperation for their protection and requiring consideration of their well-being in evaluating projects that emit greenhouse gases.
The decline in sea ice in the Bellingshausen Sea can be attributed not only to human-caused climate change but also to the natural La Niña climate phenomenon in the Pacific Ocean over the past three years. The shift to El Niño conditions…
2023-08-24 16:16:14
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