AUCKLAND -- American scientists have spotted a big rookery of Emperor Penguins huddling in an area where it was feared they were on the verge of extinction because of a huge iceberg, Antarctica New Zealand (ANZ) said in a statement.

In one of the most remarkable natural events on the planet, the Emperor Penguins breed and incubate their single eggs well inland on the ice but in the depths of a fierce and dark winter.

Early this year scientists feared a vast iceberg which has blocked the Ross Ocean was threatening the survival of penguins.

Under the greatest threat, were the Emperor Penguins of Cape Crozier on Ross Island, which is also the home to the major New Zealand and U.S. bases. The Adelie penguin colonies were also badly affected as the icebergs made it impossible for penguins to search for food.

ANZ Chief Executive Lou Sanson said the Emperors were sighted at Cape Crozier on Monday, giving some hope that fears of severe penguin losses may have been unfounded, according to AFP.

A United States C17 Globemaster aircraft had flown from Christchurch, New Zealand, to MCmurdo base on a normal winter flight program and was turning back for New Zealand when they went over Crozier to allow researchers their first glimpse since last summer of the rookery.

"The penguins were in a big huddle and were photographed by an American research photographer on board," Sanson said. "While it was impossible to determine numbers, the fact that they were at the Cape was a positive sign."

He said there are usually a thousand breeding penguins at Crozier.

Penguin researchers will begin flying to Antarctica again in October with the start of the summer season to check the state of the rookeries.

An iceberg labeled B15 calved off the Ross ice shelf in March 2000 and measured around 11,000 square kilometers (4,400 square miles), the size of Jamaica.

Expected to drift out into the South Ocean, it split in two and overall measures 160 kilometers (100 miles) long by 33 to 50 kilometers (22 to 32 miles) wide. It towers 46 meters (150 feet) above the sea but 246 meters (800 feet) deep into the sea, effectively blocking MCmurdo sound and access to Ross Island.

Satellite pictures this week show only modest change in the iceberg's state, although more open ocean around it is visible.