The volcanic island of Zavodovski in the South Sandwich Islands lost more than 680,000 of its chinstrap penguins between 2011 and 2025. (AFP Photo)
A remote island near Antarctica is no longer home to the world’s largest penguin colony as climate-driven changes to ocean food chains likely devastated its once-thriving inhabitants, a new study said on Oct. 7.
Drone and satellite images showed that the volcanic island of Zavodovski lost more than 680,000, or two-thirds, of its chinstrap penguins between 2011 and 2025, according to the British Antarctic Survey (BAS).
“That’s a very rapid loss,” Norman Ratcliffe, the lead author of the BAS study published in the journal Current Biology, told AFP.
The study’s findings raise concerns that chinstrap populations across the South Sandwich Islands, which are home to 38 percent of the species, have fallen.
The researchers suggest that the “alarming declines” should lead to chinstrap penguins being redesignated as “endangered” by the International Union for Conservation of Nature (IUCN), a sharp downgrade from their current “least concern” classification.
The number of chinstraps on Zavodovski fell from around 1.09 million breeding individuals in January 2011 to 402,000 in 2025, a 63 percent decline, according to the study.
The island is also home to macaroni penguins, whose population rose from around 338,000 in 2011 to 433,000 in 2025. They now outnumber chinstraps.
The researchers said the Adelie penguins of Cape Adare, on the other side of Antarctica, are now the world’s largest penguin colony, numbering more than one million as of 2018.
Zavodovski’s Mount Curry volcano erupted in 2016, sparking fears that it could wipe out its penguin population. But researchers found that the ash cloud was blown northeast over an area not inhabited by the birds.
