{"id":53528,"date":"2026-11-06T15:05:00","date_gmt":"2026-11-06T20:05:00","guid":{"rendered":"https:\/\/www.ecoticias.com\/en\/?p=53528"},"modified":"2026-10-31T09:56:48","modified_gmt":"2026-10-31T13:56:48","slug":"a-remote-volcanic-island-once-home-to-the-worlds-largest-penguin-colony-has-lost-63-percent-of-its-breeding-chinstrap-penguins-and-scientists-say-the-volcano-above-them-is-not-to-blame","status":"publish","type":"post","link":"https:\/\/www.ecoticias.com\/en\/a-remote-volcanic-island-once-home-to-the-worlds-largest-penguin-colony-has-lost-63-percent-of-its-breeding-chinstrap-penguins-and-scientists-say-the-volcano-above-them-is-not-to-blame\/53528\/","title":{"rendered":"A remote volcanic island once home to the world’s largest penguin colony has lost 63 percent of its breeding chinstrap penguins, and scientists say the volcano above them is not to blame"},"content":{"rendered":"\n

Zavodovski Island, a remote volcano in the South Sandwich Islands, has lost 63 percent of its breeding chinstrap penguins since 2011. Drone flights and satellite photos by the British Antarctic Survey (BAS) show the drop, in a paper out October 7, 2026, in Current Biology<\/em>.<\/p>\n\n\n\n

So Zavodovski, hailed in 2011 as the biggest penguin colony on Earth, has lost that title. It passes to the Ad\u00e9lie penguin colony at Cape Adare in the Ross Sea, the authors write. Meanwhile, macaroni penguins on Zavodovski grew in number and now outnumber the chinstraps.<\/p>\n\n\n\n

From 542,675 nests to 201,182<\/h2>\n\n\n\n

Satellite images put the chinstrap population at 542,675 apparently occupied nests in January 2011. By January 2025, the count was 201,182. Each nest stands for a breeding pair, so the figures track breeding birds rather than every penguin on the island.<\/p>\n\n\n\n

According to the paper, the losses ran at a steady 7 percent a year or so. On the Antarctic Peninsula and the South Shetland Islands, chinstraps are falling by about 2 percent a year. On Zavodovski the birds are vanishing more than three times as fast.<\/p>\n\n\n\n

Both species together now add up to roughly 420,000 pairs on the island. Cape Adare held 504,332 Ad\u00e9lie pairs in 2018, and that colony was still growing, the study notes.<\/p>\n\n\n\n

Fifteen days at sea, one drone<\/h2>\n\n\n\n

Zavodovski lies more than 1,240 miles (2,000 kilometers) from the nearest permanent human settlement. The BAS team sailed for 15 days across stormy seas to reach it, the agency said in its press release<\/a>. The island is about twice the size of Gibraltar.<\/p>\n\n\n\n

A six-person expedition camped ashore from December 10 to 16, 2023. On December 14, a quadcopter photographed almost every nesting area while both species sat on eggs. It flew 230 to 330 feet (70 to 100 meters) above the ground.<\/p>\n\n\n\n

Software counted the nests, and the researchers checked that tally against hand counts in 114 small plots. They then compared the result with satellite pictures from 2011, 2016, 2020 to 2022 and 2025. Earlier work has shown how much satellite images of penguin guano<\/a> can reveal from orbit.<\/p>\n\n\n\n

Two flights by a Royal Air Force A400M Atlas from the Falkland Islands added oblique photos of the coast. The team also fitted satellite tags to twelve chinstraps and eight macaronis to see where they fed.<\/p>\n\n\n\n

Krill retreating toward the Weddell Sea<\/h2>\n\n\n\n

Chinstraps feed mostly on Antarctic krill, a small shrimp-like crustacean that swarms in huge numbers. The tags showed them working cooler waters northwest of the island. Macaronis headed into warmer water to the northeast.<\/p>\n\n\n\n

Professor Norman Ratcliffe, the BAS penguin ecologist who led the research, called it “a worrying decline for chinstrap penguins.” In his words, “with waters warming, the krill have moved southwards into the Weddell Sea.” Sea ice and a lack of nesting islands keep the birds from following, he said.<\/p>\n\n\n\n

A 2019 study in Nature Climate Change<\/a> found that krill in the region contracted southward during rapid warming, and Ratcliffe’s team cites it to explain the chinstrap losses.<\/p>\n\n\n\n

Chinstraps also keep to a narrow band of sea temperatures and avoid sea ice, the authors write. Hotter water squeezes them at the northern edge of their range, and the south offers ice and very little bare rock. Rising temperatures are reshaping the far south in other ways too, including the polar ice loss<\/a> measured across Greenland and Antarctica.<\/p>\n\n\n\n

Macaronis now run the slopes<\/h2>\n\n\n\n

Macaroni penguins rose by about 28 percent between 2011 and 2016 and have held steady since. In 2025 they had 216,606 nests. They can switch to fish and other crustaceans when krill runs short, BAS explains.<\/p>\n\n\n\n

Ratcliffe called the shift “the biggest change in community composition ever observed at a single location in Antarctica.” In the paper, the authors describe Zavodovski as moving from an Antarctic to a subantarctic state.<\/p>\n\n\n\n

\"Graph
Graphical abstract of the study: the area of chinstrap colonies on Zavodovski falls steadily from 2011 to 2025, while macaroni colonies grow to 2016 and then level off. (Image: Ratcliffe et al. \/ Current Biology, CC BY 4.0)<\/figcaption><\/figure>\n\n\n\n

Other clues in the drone images point the same way, including 1,265 Antarctic fur seal pups and four breeding attempts by king penguins. Both species have their regional population centers on South Georgia, farther north.<\/p>\n\n\n\n

The gains are local, though, because macaroni numbers have fallen at South Georgia, the species’ stronghold in the Scotia Sea, according to the study.<\/p>\n\n\n\n

The decline predates Mount Curry<\/h2>\n\n\n\n

Mount Curry, the island’s volcano, erupted in March 2016 and sent an ash cloud northeast across Zavodovski. Yet the chinstrap decline was under way before the eruption. It kept the same pace afterward, with no sudden drop, the authors found.<\/p>\n\n\n\n

Penguins also avoid nesting on Asphyxia Plain, downwind of the crater, which probably limited the damage. Competition for space looks unlikely too, since large patches of old chinstrap ground now sit empty.<\/p>\n\n\n\n

Krill fishing around the South Sandwich Islands ceased in the early 1990s, the paper says. Closed zones of the marine protected area now cover almost 80 percent of the chinstraps’ time at sea.<\/p>\n\n\n\n

Humpback whales eat a share of the local krill. But krill stocks were already falling before the whales recovered, the authors note, so whales are unlikely to be the sole cause.<\/p>\n\n\n\n

Candlemas, Visokoi and Saunders uncounted<\/h2>\n\n\n\n

The new survey covered only Zavodovski, while Candlemas, Visokoi and Saunders islands each held more than 150,000 chinstrap pairs in 2011. Nobody in this study counted them, so the authors call for new surveys there to see how far the losses reach.<\/p>\n\n\n\n

Those counts could decide how the species is classed. Right now the IUCN lists chinstraps as Least Concern. If the losses are typical of the islands and continue, the global trend meets the criteria for Endangered, the authors calculate.<\/p>\n\n\n\n

The IUCN moved emperor penguins<\/a> to Endangered six months earlier, BAS recalls. Peter Fretwell, a BAS remote sensing researcher and coauthor, said the islands are “home to almost a third of the world’s chinstrap penguins \u2013 but not even they can escape the impacts of climate change.”<\/p>\n\n\n\n

The full study was published in Current Biology<\/a>.<\/p>\n\n\n\n

Photo: John Dickens \/ British Antarctic Survey<\/p>\n","protected":false},"excerpt":{"rendered":"

Zavodovski Island, a remote volcano in the South Sandwich Islands, has lost 63 percent of its breeding chinstrap penguins since … <\/p>\n

Read more<\/a><\/p>\n","protected":false},"author":14,"featured_media":53507,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"eco_video_url":"","footnotes":""},"categories":[3],"tags":[],"class_list":["post-53528","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-environment","resize-featured-image"],"_links":{"self":[{"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/posts\/53528","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/users\/14"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/comments?post=53528"}],"version-history":[{"count":1,"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/posts\/53528\/revisions"}],"predecessor-version":[{"id":53578,"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/posts\/53528\/revisions\/53578"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/media\/53507"}],"wp:attachment":[{"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/media?parent=53528"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/categories?post=53528"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ecoticias.com\/en\/wp-json\/wp\/v2\/tags?post=53528"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}