Europe South Asia Asia Pacific Americas Middle East Africa BBC Homepage World Service Education

Front Page



UK Politics







Talking Point
On Air
Low Graphics

Monday, November 9, 1998 Published at 15:49 GMT


Walruses 'threatened by climate change'

Arctic Walrus threatened by retreating and thinning ice

By Environment Correspondent Alex Kirby

The environmental campaign group Greenpeace says it has found evidence that walruses and other Arctic species are being affected by climate change.

It says some of the species affected are barometers of the changes taking place, and are a clear warning that more change is inevitable.

The crew of a Greenpeace vessel, the Arctic Sunrise, which recently sailed along the edge of the Arctic pack ice between Alaska and the Chukotka region of Russia, found that the edge of the ice was much further north than usual.

Greenpeace campaigners say the edge of the ice is normally only a few tens of miles north of Point Barrow in Alaska.

But this year they found it was at least 150 nautical miles north of the settlement, retreating towards the North Pole.

Walruses need thick ice

Walruses use the pack ice for resting and breeding. An adult male weighs getting on for two tons, and a female about half of that.

Global warming
The thinner ice cannot support weights like these, so the animals' habitat is shrinking.

The walruses dive for food to the seabed, where they feed on molluscs and other invertebrates.

But with the ice so far further north than usual, the edge of the pack is now over much deeper water than the walruses are used to.

As the ice edge retreats beyond the continental shelf waters of the Chukchi Sea, Greenpeace says, the water could be too deep for the walruses to dive for food.

Breeding affected

Dr Brendan Kelly, of the School of Fisheries and Ocean Sciences at the University of Alaska, who was on the Arctic Sunrise, says the ratio of walrus cows to calves is much lower than he would like to see.

"If the trend continues," says Dr Kelly, "we will definitely see a decline in the population. That may very well be due to the retreat of the ice".

The Greenpeace expedition also says it found problems with some Arctic seabirds, especially the black guillemot. It says the birds' numbers were quite healthy during the 1970s and 80s, but that they have fallen dramatically since then.

The guillemots nest on shore but, like the walruses, they depend entirely on food found at the edge of the pack ice.

Dr George Divoky, of the Institute of Arctic Biology at the University of Alaska, says black guillemot are "like the proverbial canary in the coal mine".

They and similar species "are an excellent indicator of climate change, because the effects of warming on these habitats are direct and immediate".

"The guillemots are trying to tell us that Arctic Alaska has changed greatly in the last thirty years, and more changes are on the way."

Advanced options | Search tips

Back to top | BBC News Home | BBC Homepage |

Sci/Tech Contents

Internet Links


University of Alaska

Mammal Research Unit - St Andrew's University

The BBC is not responsible for the content of external internet sites.

In this section

World's smallest transistor

Scientists join forces to study Arctic ozone

Mathematicians crack big puzzle

From Business
The growing threat of internet fraud

Who watches the pilots?

From Health
Cold 'cure' comes one step closer