Warmer, wetter weather in Canada's North could have a devastating impact on nesting seabirds, says a biologist with the Canadian Wildlife Service in Iqaluit.

Mark Mallory says he and his colleagues have examined research data on seabirds collected over the past 33 years and have tracked the unusual ways they die. They predict a warming climate, including more frequent and severe storms, will have serious implications.

"It's not really a surprise," says Mallory. "If a bird is adapted to cold conditions and you make things warmer, predictably they'll find things harder."

The birds he and his colleagues studied died most often as a result of violent storms, crashing into each other or into cliffs during heavy fog.

They also died after being slammed into the ocean by strong winds or from a combination of heat stress and blood loss due to mosquito attacks.

The scientists' research was published earlier this month in the peer-reviewed journal, Arctic. Their study is based on the observation of six species of birds in 11 seabird colonies in the Eastern Arctic from northern Hudson Bay to Devon Island.

Few birds spend their winters in the Arctic's harsh climate, but come spring they arrive in large numbers to nest, spending the summer on cliff faces.

800 birds killed

In one dramatic incident, Mallory's colleagues saw a whole section of cliff breaking off, instantly killing 800 nesting birds. He says cliffs may become unstable as temperatures rise and they experience more freeze-thaw cycles.

"I saw one spectacular avalanche at Qaquluit, south of Qikiqtarjuaq, where the snow came down (the cliff) and you could see all the nesting fulmars caught in the snow," Mallory said.

"They couldn't get out, so you could see their wings tumbling as they were coming down … they had broken their wings when they fell off the cliff."

Meanwhile, Levi Nutaralaaq, an elder in Qikiqtarjuaq, says he has seen polar bears eating the fulmars' eggs.

Mallory says that too may be linked to warmer temperatures and the earlier breakup of winter sea ice. Polar bears hunt almost exclusively from the ice during the winter and eat only sparingly after spring breakup forces them onto the land.

But with less time to hunt on the ice, hungry polar bears may be climbing cliff sides to raid nests for food.

"It's always shocking to see a polar bear on a cliff," says Mallory.

"I saw Arctic foxes down what appeared to be effectively a vertical wall. And the Inuit report seeing more polar bears on cliffs. So these birds think they are safe, but they are not."