For emperor penguins, sea ice is essential to survival. The iconic birds, found only in Antarctica, breed, lay their eggs, and raise their chicks on fast sea ice (meaning it is attached to land). They arrive at their breeding sites in late March. In May and June, they lay their eggs, which hatch after 65 days during the cold Antarctic winter. The chicks then remain on the ice until their fluffy down is replaced by waterproof feathers. In addition, they also rely on stable sea ice for protection from predators.
就帝企鵝來說,海冰的存在對于生存至關(guān)重要。這種標(biāo)志性鳥類只見于南極洲,它們在堅(jiān)硬的海冰上(意味著它附著在陸地上)繁殖、產(chǎn)卵和養(yǎng)育幼崽。它們于每年3月下旬抵達(dá)繁殖地。5月和6月,它們產(chǎn)卵,卵在65天后,即在南極嚴(yán)酷的冬季孵出。然后,雛鳥會留在冰面上,直到它們蓬松的絨毛退化,長出防水的羽毛。此外,它們還依靠穩(wěn)固的海冰來免受捕食者的侵害。
In 2022, sea ice levels in Antarctica were at an all-time low. The Bellingshausen Sea region, to the west of the Antarctic Peninsula, saw the most serious reduction of sea ice, with some areas experiencing a 100-percent loss.
Of the five known emperor penguin groups in the Bellingshausen Sea region, all but one experienced what was most likely a total breeding failure because of the loss of sea ice, according to a paper published in Communications Earth amp; Environment. Satellite imagery clearly showed the sea ice had broken up before the chicks would have developed enough to survive on their own.
2022年,南極洲的海冰高度創(chuàng)下歷史新低。位于南極半島西部的別林斯高晉海地區(qū)的海冰減少最為嚴(yán)重,部分地區(qū)的海冰已不復(fù)存在。
據(jù)《通訊·地球與環(huán)境》上的一篇文章介紹,在別林斯高晉海地區(qū)已知的五個(gè)帝企鵝群中,只有一個(gè)帝企鵝群沒有遇到由于海冰消失讓繁殖很可能徹底失敗的情況。衛(wèi)星圖像清楚地顯示,在雛鳥發(fā)育到足以獨(dú)立生存之前,海冰就已經(jīng)破裂了。
“We have never seen emperor penguins fail to breed at this scale in a single season,” the study’s lead author, Peter Fretwell of the British Antarctic Survey, said in a statement. “The loss of sea ice in this region during the Antarctic summer made it very unlikely that displaced chicks would survive.”
The study team also estimate their findings support a projection that, if present warming rates continue, more than 80 percent of emperor penguin groups will be nearly extinct by 2100. The recent breeding failures “could be a snapshot of what happens in a future Antarctica,” says Norman Ratcliffe of the British Antarctic Survey, a co-author of the new study.
The biggest threat to emperor penguins is undoubtedly climate change. As the world warms, sea ice will decline and emperor penguins—as well as other animals—will likely follow suit. Jeremy Wilkinson, a sea ice physicist also at the British Antarctic Survey, stated that the breeding failure “dramatically reveals the connection between sea ice loss and ecosystem destruction”.
For species such as the emperor penguin, the crisis is already underway. “There is no time left,” Wilkinson says.
該文章的主要作者、英國南極調(diào)查局的彼得·弗雷特韋爾在一份聲明中表示:“我們從未見過帝企鵝在一個(gè)繁殖季如此大規(guī)模地繁殖失敗。在南極的夏季,該地區(qū)消失的海冰使得流離失所的小企鵝很難生存。”
研究小組還預(yù)測:如果以目前的變暖速度持續(xù)下去,到 2100年,超過80%的帝企鵝群落將瀕臨滅絕。這項(xiàng)新研究的合著者、英國南極調(diào)查局的諾曼·拉特克利夫說,近來的繁殖失敗“可能是南極洲未來狀況的縮影”。
帝企鵝面臨的最大威脅無疑是氣候變化。隨著地球變暖,海冰將會減少,帝企鵝以及其他動物可能也會減少。英國南極調(diào)查局的海冰物理學(xué)家杰里米·威爾金森表示,這次繁殖失敗“讓海冰消失與生態(tài)系統(tǒng)破壞之間的關(guān)聯(lián)昭然若揭”。
對于帝企鵝等物種來說,危機(jī)已經(jīng)到來?!皼]有時(shí)間了?!蓖柦鹕f。