New York: The entire population of Antarctica’s famous emperor penguins could fall by a third by the end of the century because of disappearing sea ice, putting them at risk of extinction, say researchers.
Writing in the journal Nature Climate Change, scientists from Woods Hole Oceanographic Institution in Massachusetts say their findings justify protecting emperor penguins under the Endangered Species Act — as the US already does for polar bears.
They also call for marine reserves to be created to buffer the fish stocks penguins need to survive. “The population is declining. Unless something changes to stop that, the population will go into extinction,” said Hal Caswell, one of the authors of the study.
As a top predator in Antarctica, penguins are mainly at risk from climate change, which is melting the sea ice.
The loss of ice is reducing the supply of krill, the tiny, shrimp-like crustaceans that populate the Southern Ocean and are the emperor penguins’ main food source. Young krill feed off algae living in the sea ice. When the ice goes, so do the krill.
Changes in the ice around Antarctica may — in the short term — boost some of the emperor penguin populations, especially along the Ross Sea, the researchers said. Sea ice off the western coast of Antarctica has been on the increase, because of wind conditions and the break-up
But by 2100, all 45 known emperor penguin colonies of Antarctica will be on the decline because of loss of sea ice. Those located on the coasts of the eastern Weddell Sea and the western Indian Ocean will show the sharpest drops. Nine colonies are projected to be “quasi-extinct”, the researchers said.
Other studies have raised the threat to emperor penguins under climate change, suggesting the ordinarily hardy animals, which grow to more than a metre high, are susceptible to rising heat. Smaller penguins such as the chinstrap and Adelie are also at risk.
Researchers from the University of Minnesota last week suggested some emperor penguin colonies might be able to move location and so be better equipped to adapt to changing ice conditions than previously thought.