At stake is a growing and lucrative business for Inuit hunters, who sell the skins as a byproduct of their traditional hunt. A defeat would also be a "warning" to Canada's self-image as a responsible steward of the mighty Arctic predator.
Early next month, countries from around the world will meet in Bangkok to consider changes to the Convention on International Trade in Endangered Species. Among the proposals is one from the United States that would place polar bear hides, heads or other parts in the same category as elephant ivory, forbidding their cross-border sale.
Canada fought off a similar proposal in 2010 with help from the European Union, which voted in a bloc to defeat it.
Now, major countries, including the United Kingdom and Netherlands, have announced they support a ban. Russia, which has polar bears, also agrees with the U.S.
Germany, Austria, Belgium and Poland are on-side with the change. Former opponents of the tougher rules, such as Spain, Greece and France, are now undecided. Meetings last week intended to develop a united EU position ended in deadlock.
The best Canada can now hope for is for the EU to abstain, said Dan Ashe, a director with the U.S. Fish and Wildlife Service.
"We have enough votes that the EU can't oppose (our proposal). There aren't enough votes left for the EU to get to a position of opposition."
An official with the European Commission confirmed early Sunday the body "is still finalising its position."
Canada — the only country that allows trade in polar bear parts — has long maintained that bear populations are healthy and remain at between 20,000 and 25,000. Canadian officials say the real threat to the bears is climate change, not international trade. They say restricting commerce wouldn't reduce the number of bears killed because a ban wouldn't affect traditional or sport hunts.
"(The U.S. proposal) would have no conservation benefit, but would harm the livelihoods of our Inuit peoples," an Environment Canada spokeswoman said in an email.
Canada points out that environmental groups, including the World Wildlife Fund, oppose the proposal. So do international wildlife monitoring organizations.
While Ashe agrees about the source of the real threat, he says the growing market for polar bear hides and other products is adding another stress by encouraging hunters to kill more.
"What we've seen is the harvest of bears has been going up and the trade has been going up.
"When we create markets for rare animals, history tells us that ultimately those markets are difficult to stop once they are established and people are making money. I think that's what we've been seeing with polar bears."
Last week, the European Commission's environment commissioner, Janez Potcnik, told the European Parliament that a decision on the convention would be made by scientific evidence.
"We will define our position on these on the basis of the criteria agreed by the CITIES partners, which rely on science and the need to convince local populations to participate in the protection of wildlife so it can be successful," Potcnik said.
Figures compiled by the U.S.-based Natural Resources Defense Council suggest the yearly number of polar bear skins offered at auction increased 375 per cent between 2007 and 2012, from 40 to 150. As well, the average price doubled to about $5,200 for a single skin.
At the same time, harvest quotas for the bears have increased — dramatically, in some regions. An Inuit co-management board tripled the quota in 2011 for the western Hudson Bay population.
About 800 bears are taken each year. Estimates suggest up to 500 skins hit the market.
International scientists say that of Canada's 13 bear populations, one is increasing, three are stable and six are declining. Not enough is known about the other three to judge.
But some of that evidence is conflicting. A recent Nunavut government survey of the western Hudson Bay population counted two-thirds more bears than official estimates had suggested — although it found the number of young bears far lower than needed.
"The scientific data from studies clearly shows the international trade is sustainable," said James Eetoolook of Nunavut Tunngavik Incorporated, which oversees the Nunavut land claim and has lobbied against the U.S. proposal in Europe.
"We have one of the better management systems in Canada. It does not threaten the health of the bears at all."
He said international trade simply allows hunters to get the most value from bears they would have harvested anyway.
"We always look for the best market. The international market is good right now and we don't want to lose that."
The cash is welcome in tiny, remote communities with high living costs and few other options, he said.
Andrew Derocher, a University of Alberta polar bear biologist, said the U.S. proposal is unlikely to reduce the bear harvest.
"I don't see a need for it right now," he said in an email. "Hunting, if sustainable, as it is in some populations, can continue without serious effects in some populations."
The problem, he said, is that not all quotas are sustainable.
"Mixing sustainable harvest with unsustainable harvest in an international market makes us vulnerable to the anti-hunting lobby."
Ashe said Canada should pay heed to growing global discomfort with its polar bear management.
"It's a warning, it definitely is. I think there's a need to do that because of the increase in commerce that we're observing."
But Eetoolook said the issue is more about global discomfort with hunting cultures.
"There's people in the world that probably want to see the extinction of the Inuit because they hunt animals.
"Hunting has been our tool to get an income. It's kind of hard being Inuk sometimes when people that don't know anything about wildlife try to tell you you're overhunting."
Meanwhile, a spokeswoman for the president of the EU Council said both Canada and the U.S. have been sent letters asking them to consider "possible alternatives" to the proposed trade ban.
The EU is expected to adopt a final position on the issue on Feb. 28. The CITES meetings run from March 3-14.
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