Antarctic penguin mystery

Adelie penguins are found right across the continent

From Christine McGourty, science correspondent, in Antarctica

A mystery disease is killing penguins in Antarctica.

Pygoscelis adeliae: Among the most abundant of the Antarctic penguins

Australian scientists have found over 100 penguins dead near their Mawson base.

They fear there could be many more. It is not unusual to find one or two dead penguins in a colony, but this kind of large-scale mortality is rare. The scientists fear an unknown disease is responsible and are concerned that it could spread.

They have restricted human access to the penguins.

Abundant numbers

They are also disinfecting boots and clothing after leaving the area. Blood and tissue samples are being taken from the birds and will be sent by ship for analysis in Australia in the next few days.

Adelie penguins

Distribution: Continent and Antarctic islands

Distinguishing feature: They have a white ring around the eye

Size: 75 cm

Weight: 3 to 6.5 kg

Diet: Almost exclusively krill

The penguins affected are called Adelie penguins (Pygoscelis adeliae) and they are among the most abundant of all the penguins in the Antarctic, so the species is under no imminent threat.

There are about 15,000 in the Australian colonies at Mawson and over two million worldwide. But their numbers have been declining here in Antarctica and it is thought that climate change may be to blame.

They are losing some of the ice that is their natural habitat. Keith Reid, an expert in penguins at the British Antarctic Survey, says there is no cause for immediate alarm at the disease outbreak.

Lost chicks

"The Australians are very concerned about the potential for humans introducing disease into penguin colonies. But if this was an externally introduced disease, it would go through a colony extremely rapidly."

He said one possibility was that skuas (Antarctic seabirds) travelling large distances while scavenging around the oceans could introduce disease into a penguin colony.

It has also been a bad year for the thousands of Emperor penguins living near the British base at Halley.

The ice broke up early this year, before the chicks were old enough to fend for themselves. And it is thought that most of them have drowned or died of hypothermia.