The view that climate change is mainly driven by natural cycles, not by human-caused pollution, does not help polar bear conservation efforts, according to Andrew Derocher, former chairman of the Polar Bear Specialist Group. (CBC)

A polar bear biologist formerly from Nunavut was barred from an international scientific meeting because his beliefs on climate change and its effects on the species are inconsistent with the group's opinion.

Mitch Taylor, who was a polar bear biologist with the Nunavut government until last year, was not invited to the Polar Bear Specialist Group's meeting in Copenhagen, Denmark, this past weekend.

The group of scientists meets periodically to discuss the status of polar bear populations around the world. Taylor said he had been attending the group's meetings since 1981.

Dissenting view 'extremely unhelpful'

But in email correspondence obtained by CBC News, then-chairman Andrew Derocher told Taylor that his beliefs about climate change — that it is a natural cycle, not mainly driven by human-caused pollution — are not "helpful" to the group.

"I do believe, as do many [Polar Bear Specialist Group] members, that for the sake of polar bear conservation, views that run counter to human-induced climate change are extremely unhelpful," Derocher, a polar bear researcher at the University of Alberta, wrote in his email to Taylor.

"I, too, was not surprised by the members not endorsing an invitation. Nothing I heard had to do with your science on harvesting or your research on polar bears," Derocher added in the message, dated June 15.

"It was the positions you've taken on global warming that brought opposition."

Taylor retired from Nunavut's Environment Department last year and moved to Ontario, but he said he is still involved in polar bear research.

"I feel actually disappointed, sad, because I don't think this is how science should work," Taylor told CBC News.

"I don't think the credibility of the specialist group was served by this decision."

Membership limited, chairman says

In an email to CBC News, Derocher said involvement in the Polar Bear Specialist Group is limited to those who are active in polar bear research and management.

Taylor no longer fits those criteria, said Derocher, whose term as group chairman ended last week.

Taylor said he believes the Arctic has warmed, but said it's more related to natural cycles with just some impact from human-caused pollution such as greenhouse gases.

While he said polar bear populations in some areas, such as the western Hudson Bay region in Nunavut, have been adversely affected by the changing climate, he said predictions that polar bears will disappear because of climate change are overblown.

"Even though you might see a shrinking of the range of polar bears — maybe in some of the southern areas, maybe a reduction in numbers and productivity and in some, maybe all of the populations — you're not looking at something that would cause polar bears to go extinct," he said.

Sea ice shrinking, group says

In his email to Taylor, Derocher said he has no problem with dissenting views on the polar bears' survival "as long as they are supportable by logic, scientific reasoning and the literature."

Following the weekend meeting, the group concluded that the overall condition of the world's 19 polar bear populations is deteriorating due in part to shrinking sea ice.

The group says that eight bear populations are in decline — up from five in its last report in 2005. Three populations are considered stable compared to five previously.

Only one population is increasing. Information on seven populations is still too scarce for scientists to draw solid conclusions.

The report, released Monday, suggests an "unprecedented" loss in sea ice, which bears use as a seal-hunting platform, is behind the downward trend.

Because of the amount of uncertainty involved with counting polar bears, the polar bear group has kept its estimate of the global population at between 20,000 and 25,000. About two-thirds of those are believed to live in Canada.

With files from CBC's Patricia Bell, the Canadian Press