A new report says climate change could be putting Canada's Arctic whales in hot water.
The report, released Tuesday by the World Wildlife Fund, said global warming is likely having the same effect on whales that it's having on polar bears — changing the conditions under which they are adapted to live.
"It is unclear to what extent cetaceans will be able to adapt to the rate of climate change predicted in the near future," says the report.
"As temperatures increase, there are likely to be significant losses of polar 'specialist' species and a general shift of more temperate species towards the poles."
Previous research suggests the Arctic is warming at twice the rate of other parts of the globe. As well, the U.S. Snow and Ice Data Centre reports that sea ice already extends about 14 per cent less than it did in the '70s.
That could have serious implications for species such as beluga, a small white whale loved by the Inuit for its meat and blubber and by southern aquarium-goers for its smiley face, as well as narwhal, also hunted for food and renowned for the single long tusk growing out of its head.
Both whales are not only heavily dependent on the abundant life that blooms around the sea ice edge but also strongly tied to specific areas of it.
"Those two species are almost like robots," said Kristen Laidre, a marine biologist at the University of Washington who has just returned from a narwhal research trip to Greenland.
"They go to the same area year after year after year."
As climate change shifts everything from the extent of the ice cover to the time of spring breakup, no one knows how the whales will react.
"Would they move north with the sea ice? That's one of the big debatable questions," Ms. Laidre says.
Being at the right place at the right time is critical for all northern animals, and whales are no different.
"They're very much in rhythm with that system and exploit it," Ms. Laidre says. "If that (timing) changes, that's probably where the effects will be seen."
The report, entitled Whales In Hot Water?, also suggests that Arctic whales may face more competition for resources as warming oceans push whales north who would normally live in more temperate waters.
Dependable areas of year-round open water, called polynyas, could freeze over, trapping whales under the ice. As well, whales are likely to suffer from increased noise and chemical pollution as Arctic waters become busier shipping routes.
Belugas and bowheads have been seen to flee ships approaching within 35 kilometres.
"It is expected that the opening of the Northwest Passage will have a strong negative effect on cetaceans in the area, particularly when the synergistic effects of these human activities and the climate-change induced shifts in the ecosystem are considered," the report says.
Ms. Laidre says it's hard to predict the effects of climate change on Arctic whales because so little is known about them. Arctic research is both expensive and logistically difficult.
But Pete Ewins of the World Wildlife Fund says the Arctic whales face the same plight as that of polar bears. The sea ice that both shelters and feeds them is changing and — mostly — shrinking.
"The steps you need to take require you to not only turn down the (carbon dioxide) but also to be cautious and manage other activities," he said, noting that military, industrial and tourist activities in formerly silent Arctic waters are all increasing with the melting ice.
Species such as whales and polar bears are not only pop-culture icons, but also good indicators of the health of an ecosystem, said Mr. Ewins.
"They are flagships of the marine systems," he said.
"If you get it right for Arctic whales, then numerous other species down the food chain would benefit."
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