"Put simply: Climate change is forcing bears to spend more time on land where there is virtually no food. Females are 30 to 40 kilograms lighter than they were in the early 1980s. And they’re producing fewer cubs"--“When you put it all together it summarizes a population that is not reproducing sufficiently to maintain the current abundance and that means the population is in decline”----Andrew Derocher(U. Of Alberta Polar Bear Scientist)...........Derocher contends that the recent western Hudson Bay study which stated that Polar Bear populations were equal or above the levels of ten years ago is flawed.........If you truly evaluate what the latest report showed, one would notice immediately that the number of cubs and yearlings found were greatly off from historical levels..... ." According to the aerial survey — very few cubs were seen in the region where the survey took place — 50 cubs and 22 yearlings were observed"........" What’s more, average litter sizes were “the lowest recorded in recent years amongst the three Hudson Bay subpopulations, suggesting that reproductive output in WH (western Hudson Bay) was poor in 2011"

Scientist disputes claim that polar bear population is abundant

Debra Black
thestar.com

A polar bear and her cub swam between melting ice floes in late July 2011 in Canada's Baffin Bay.

A polar bear expert and professor of biological sciences at the University of Alberta is critical of the “spin” put on a recent aerial survey of polar bears in the western Hudson Bay.  The study, which was conducted on behalf of the Nunavut government, found that there are likely about 1,013 polar bears in the region, which is not significantly different from a previous mark-and-recapture or tagging study done in 2004.

This has led some to conclude that the polar bear population hasn’t significantly declined over the last seven years, despite the predictions of some scientists who have suggested that the population would decline to about 650 by 2011.

But Andrew Derocher, who has studied polar bears for 40 years, believes that the two surveys can’t be compared. It’s like comparing apples and oranges,” he explained to the Star in a phone interview. The aerial study looked at a much larger region than the tagging study, Derocher said. “Effectively you can’t compare the abundance between the mark-and-recapture survey and the aerial survey directly because they’re measuring two different things.”

Derocher believes the Nunavut Tunngavik Inc. — a company formed to advance the rights of the Nunavut land rights agreement, including the harvesting rights of the Inuit — may have “jumped the gun rather than waiting for a complete analysis” of the survey.

He suggests that perhaps some of the survey’s analysis may have been used to spin the science of climate change. NTI claimed when the report first came out that the polar bear population was abundant and healthy.  At the time the survey was released James Eetoolook, vice president of NTI, said the aerial survey proved the Inuit’s belief that “polar bears are not declining in number.” “We have reported for many years that we are seeing more and more bears on land and in communities, which raises public safety concerns,” Eetoolook said in a statement on the company’s website.

“Inuit were told by scientists the reason there are more bears in communities is due to a decline in the condition of the population, but Inuit disagreed with this interpretation,” said Eetoolook. “For many years, Inuit asked the territorial government to conduct summer range aerial surveys. Finally, in 2011, that aerial survey was conducted and as Inuit knew, the population was found to be healthy and abundant.  He continued: “This is not climate change. This is about how polar bears were used to draw attention to climate change. Changes were not made to reduce the causes or impact of climate change, but changes were made to the harvesting quotas. It was dangerous and wrong for scientist to use incomplete data to make predictions.”

But Derocher disagrees, suggesting the NTI is “trying to discount 40 years of research,” said Derocher.  What is critical in the latest report is the number of cubs and yearlings found, he explains. Those numbers are substantially down. According to the aerial survey — very few cubs were seen in the region where the survey took place — 50 cubs and 22 yearlings were observed. What’s more, average litter sizes were “the lowest recorded in recent years amongst the three Hudson Bay subpopulations, suggesting that reproductive output in WH (western Hudson Bay) was poor in 2011, the aerial survey concluded in its summary of findings.

That suggests to Derocher something serious is going on. Derocher believes that two to five times more cubs were born in the 1980s through to the 1990s. In recent years Derocher and others have seen a decline in body weight of the bears, leading to a cut in cub production and cub survival. “The aerial survey study is consistent with those findings,” he said. “The science of the effects of climate change on polar bears in Hudson Bay is absolutely profound — and that is that basically the loss of sea ice reduces the body conditions of bears and bears with lower body condition produce fewer cubs and the bears collectively have lower survival rates.”

Put simply: Climate change is forcing bears to spend more time on land where there is virtually no food. Females are 30 to 40 kilograms lighter than they were in the early 1980s. And they’re producing fewer cubs. “When you put it all together it summarizes a population that is not reproducing sufficiently to maintain the current abundance and that means the population is in decline.”

This isn’t just the case in the western Hudson Bay, but it is a pattern being repeated in other parts of the Arctic, Derocher said. What is at the heart of the debate is the intense interest in northern communities to hunt polar bears, Derocher said “This has always been a struggle. Canada has always historically been a leader in the management of polar bear harvest, but over the last 10 to 15 years there has been a drift from precautionary management and this leads us into more of a precarious situation in terms of the international community and how they view our management system of polar bears,” Derocher said.

Derocher suggests that the comments by Nunavut Tunngavik Inc. were “unfortunate” and will undervalue the science of what was done in the aerial survey. “If we try to use it as a propaganda tool the international community won’t buy it,” he said. Canada’s right to export polar bear hide could come under fire next year when the Convention on International Trade in Endangered Species meets. Historically, polar bear hide and fur has been exported to Europe and Japan mainly for rugs. But in recent years Russia and China have become leading importers of polar bear hide.