Tuesday, September 14, 2010

Canada's muskoxen down 80% due to starvation caused by climate change (report "Extinction: It's Not Just For Polar Bears" lead author Shaye Wolf)

Warming Arctic pushes wildlife to the edge




The Arctic is warming at a rate almost twice the global average, triggering mass starvation of wildlife and a doubling of coastal erosion in some areas, a new report says.

An estimated 20,000 muskoxen starved to death in one year in northern Greenland and Canada as a result of a 50% increase in ''rain-on-snow events," according to a study by the Washington-based Centre for Biological Diversity and Care for the Wild International.

Because of warming temperatures, snowfalls are replaced by freezing rains that fall on snow, creating a hard ice crust that prevents the muskoxen breaking through to forage on moss and lichen below the snow. Canada has had an 80% decline in muskoxen in its high Arctic regions as a result of starvation.

The report, Extinction: It's Not Just for Polar Bears, examines the impact of climate change on 17 Arctic species ranging from the sea butterfly a tiny marine snail dubbed the potato chip of the sea because of its importance as a food source to whales, seals, birds and polar bears.

The centre's climate science director and report's lead author, conservation biologist Shaye Wolf, said some Arctic species had already experienced widespread die-offs and population declines after losing food sources and habitat. Others faced threats from extreme weather events or new pressure from predators, parasites and pathogens moving northward.

''The polar bear is the best-known victim of rapid melting in the Arctic, but if we don't slash greenhouse pollution, many more creatures will follow it down the path to extinction,'' Dr Wolf said.

Loss of Arctic sea-ice is forcing female walruses to calve on land, where the pups are vulnerable to predators and risk being crushed or trampled when walrus colonies are alarmed by predators and adults stampede to the water.

The report estimates up to 4,000 pups were killed during a recent walrus stampede in Siberia.

Poor snow conditions have also affected lemming populations in Norway, leading to breeding failures and a dramatic decline in Arctic foxes which rely on a seasonal peak in lemmings numbers to feed their young.

Dr Wolf said red foxes were also moving northwards, competing with the smaller Arctic foxes for food and habitat.

For more on this story, including details of further impacts of warming on the region, see the print edition of today's Canberra Times.

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