Environment: Climate change threatens bears

Thousands of polar bear cubs could be killed by a dramatic temperature rise in the Arctic, which is melting their dens and destroying their food, environmentalists warn today.

A North Pole expedition by environmentalist group Greenpeace revealed an "alarming" rate of global warming which could threaten the existence of the polar bear and other unique Arctic wildlife.

Expedition leader Steve Sawyer told PA News from the group's boat on the Arctic Ocean: "There is so little ice here we cannot tell the difference between the ocean and the North Sea. It is very alarming.

"The early Spring thaw has meant polar bear dens have collapsed, potentially smothering cubs or exposing them to harsh Arctic weather too soon. The reduction in ice affects the entire ecosystem, from seals to fish, which is the bears' food."

Dr Vera Alexander, an expert on ice-edge ecology at the University of Alaska, involved in the expedition, said: "The continued decline of sea ice will affect the production of algae, which lives beneath the ice and forms the very base of the Arctic food chain.

"Without the algae, there would be no possibility of a food chain as we know it, affecting fish, seals and polar bears."

Greenpeace is calling for a halt to expanding oil industry in the Arctic regions, which it claims is damaging the environment.