The world's largest penguin colony, located on Zavodovski Island in Antarctica, has experienced a two-thirds decline in its chinstrap penguin population since 2011, according to a new study.
Scientists suggest the climate crisis is the most probable cause for this significant reduction. Prof Norman Ratcliffe, a penguin ecologist at the British Antarctic Survey and leader of the research, described it as "an enormous population crash," equating to the loss of half a million breeding individuals from the island.
The study, published in Current Biology, indicates that the speed of this collapse may be accelerating. Researchers warn that the rapid demise of these chinstrap penguins could increase the risk of a wider ecosystem collapse.
Human-driven heating has led to winter temperatures around the Antarctic peninsula rising by 5C above preindustrial levels. Chinstrap penguins, which primarily feed on Antarctic krill found in cooler waters, are struggling to adapt as warming waters cause krill to move southwards.
While macaroni penguins on the island saw a 30% increase in numbers, this was not enough to offset the chinstrap losses. Scientists ruled out other factors such as competition for food, human presence, or the 2016 volcanic eruption as primary causes for the chinstrap decline.