Changing climate a threat to penguins
Colonies likely to dwindle
Scientists are warning colonies of emperor penguins could be on the brink of extinction by the century’s end due to climate change.
They face the threat of sea ice thawing in Antarctica.
New Zealand and the rest of the world embraced the species when an emperor penguin, later dubbed Happy Feet, washed up with a belly full of sticks and sand on the Kapiti Coast in 2011.
Fans followed the castaway bird’s epic survival saga as vets nursed him to recovery until he was released back into the Southern Ocean with a tracking device.
But new research predicts the 45 known emperor penguin colonies along the Antarctic coast will be in decline by 2100, with twothirds of colonies expected to shrink to less than half of present numbers.
The findings, reported this week in journal Nature Climate Change, are based on forecast shifts in Antarctic sea-ice concentration under climate change.
The study from the Woods Hole Oceanographic Institution in the US warns at least three-quarters of colonies are vulnerable to future sea ice change, and 20 per cent will probably be near the edge of extinction by the turn of the century.
Emperor penguins breed and raise their young almost solely on sea ice – changes in ice cover impact the entire Antarctic food web through key organisms, such as krill.
The US scientists modelled population trends for the colonies, taking account of sea-ice conditions projected by a range of climate models and found that although year-to-year colony populations would mostly grow until 2040, all colonies will begin to dwindle by 2080.
Landcare Research ecologist Phil Lyver lead a team which released a study in 2010 predicting about half of Emperor penguin colonies – 40 per cent of the breeding population – north of 70 degrees South would decrease or disappear by about 2050 as average troposphere temperatures reach 2 degrees Celsius above preindustrial levels.
Lyver said the species was a ‘‘bellwether’’ that sounded an ecological alarm.
The research has implications for New Zealand’s management of the Ross Sea dependency, which he said was a haven for many species forced out of other parts of Antarctica.
‘‘It’s one of the last bastions, so New Zealanders really need to look hard at making the Ross Sea a marine protected area. We want to show on a global stage that we are responsible managers of the environment.’’
Lyver said he agreed with the researchers who advised the International Union for Conservation of Nature to upgrade the species’ conservation status from not threatened to vulnerable or endangered.