Penguins chicks at risk as iceberg blocks sea

TENS of thousands of Antarctic penguin chicks could starve to death in the next few weeks as a huge iceberg blocks access to coastal feeding grounds, a New Zealand official said yesterday.

A 1,200-mile-square iceberg, known as B15A, could also block the sea route used to supply three science stations during the southern hemisphere summer, said chief executive of the government scientific agency Antarctica New Zealand, Lou Sanson.

The iceberg has blocked sea ice flows from McMurdo Sound as it moves at a speed of 1.2 miles a day. US researchers have estimated that B15A contains enough fresh water to supply Egypt's Nile River complex for 80 years, Sanson says.

He called the iceberg "the largest floating thing on the planet right now" and said it could block four supply ships due to arrive in Antarctica in a month.

Some 3,000 breeding pairs of Adele penguins on Antarctic's Cape Royds face a 112-mile round trip to bring food to their chicks because their access to ocean feeding grounds has been cut by the ice build-up.

"So by the time a penguin comes in from the ice edge on a return 112-mile walk they've used all the food they gathered when they reach their nests," he said.

"Penguin researchers are predicting that the annual hatching is pretty certain to fail," Sanson said, meaning most chicks will die.

Scientists also fear that only about 10% of the 50,000 breeding pairs of Adele penguins at nearby Cape Bird will rear a chick this season, Sanson added.

Adult penguins there face a 60-mile round trip across the ice to reach open water and food.

Antarctica New Zealand is working with the US and Italian Antarctic programmes on alternatives for receiving vital fuel supplies for their science bases in late January.

A US icebreaker, fuel tanker and cargo ship plus an Italian cargo vessel are due to deliver a year's supply of fuel and food at that time.

The alternatives are to break an 81-mile channel through the pack ice to reach Winter Quarters Bay on the McMurdo Sound coast or offload the fuel and other supplies on the ice edge, pumping fuel through temporary lines several miles to storage tanks, he said. All Antarctic bases have contingency supplies of a year's food and fuel, Sanson says. Currently there is "more fast (blocked) ice in McMurdo Sound than we've ever recorded in living history for this time of year," he said, adding that the iceberg has been stopping normal winds and water currents from breaking up sea ice in McMurdo Sound. New Zealand penguin research scientist Peter Wilson said the ice blockage "is a very serious event for these colonies."

Mr Wilson expected the Cape Royds birds would fail to breed and the bulk of the Cape Bird chicks could die.

"It could all fail ... and more than 50,000 souls (penguin chicks) will have gone west again," he added.

However Mr Wilson, New Zealand's Adele penguin colonies project leader, said he was sure all the colonies would survive though their numbers could decline by up to 70%.