Saturday, 13 February 2016

A colony of penguins headed for extinction

Giant iceberg kills 150,000 Adélie penguins in Antarctica

Adelie Penguins diving into the water at Hope Bay, Antarctic Peninsula.
Adelie Penguins diving into the water at Hope Bay, Antarctic Peninsula. Photo: Courtesy of Wikimedia Commons

12 February, 2016

An entire colony of Adélie penguins is heading for extinction after an iceberg larger than the country of Luxembourg grounded at Commonwealth Bay, blocking access to the sea and forcing the penguins to travel considerably longer distances to feed.
The population of the Adélie penguins in this colony has plummeted from 160,000 to 10,000 since the iceberg labeled B09B came aground in 2010 after floating around the Southern Ocean for 20 years, according to The Sydney Morning Herald and a just-released study in Antarctic Science.
The iceberg trapped the Adélie penguins. The colony once thrived with easy access at Cape Denison in Commonwealth Bay where strong winds blowing off the ice kept a large area of water open near shore.
A group of Adelie penguins on an iceberg. But once the iceberg grounded, the distance to the feeding grounds became a 75-mile round trip.
In contrast, another population of Adélie penguins on the eastern fringe of Commonwealth Bay just five miles from the edge of the fast ice (sea ice fastened to the coastline) is thriving. This led researchers to believe the iceberg and fast ice expansion was responsible for the population decline.

A group of Adelie penguins on an iceberg. Photo: Courtesy of Wikimedia Commons
Adélie penguins return to the colony where they were hatched and attempt to return to the same mate and nest, and they don’t deviate from this lifestyle.
They don’t migrate,” Chris Turney, professor of Climate Change and Earth Sciences at the University of New South Wales, told the Morning Herald. “They’re stuck there. They’re dying …
The ones that are surviving are clearly struggling. They can barely survive themselves, let alone hatch the next generation. We saw lots of dead birds on the ground … it’s just heartbreaking to see.”
The iceberg is 60 miles long and covers 1,120 square miles. Unless it relocates or the perennial fast ice breaks up, the entire colony of Adélie penguins at Cape Denison could be destroyed by 2020, the study revealed.
As the planet warms you’re going to get more ice melting,” Turney told the Morning Herald. “The reality is, more icebergs will be released from Antarctica and just embed themselves along the coastline, and make the travelling distances for some of these colonies even further than they have been.”
In a bit of promising news, the fast ice associated with the iceberg has begun to break up in Commonwealth Bay in the past year, co-author Chris Fogwill of the UNSW Climate Change Research Center told the Morning Herald.

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