Hunger driving polar bears into sights of hunters

If hunters think they’re seeing more polar bears, that’s probably because the animals are starving and searching for more food.

This is the message from an article published this month in the journal Arctic by two polar bear scientists, Ian Stirling of the Canadian Wildlife Service and Claire Parkinson, a senior scientist at NASA’s Goddard Space Flight Center, who suggest warmer temperatures in the polar region are causing several populations of polar bears in the Canadian Arctic to decrease in numbers.

Their study looked at polar bears in five populations – the Western Hudson Bay, Eastern Hudson Bay, Foxe Basin, Baffin Bay and Davis Strait – where the animals must fast on their stored fat for several months during the open water period in summer and fall.

In 2005, the Government of Nunavut granted increases to hunting quotas in four of these populations.

Scientists have linked earlier breakups to poorer physical conditions in polar bears in the Western Hudson Bay. There, from 1980 to 2004, the animals’ average weight has declined by 65 kilos to 230 kilos. Below 189 kilos, another study shows polar bears have trouble reproducing.

The paper, Possible Effects of Climate Warming on Selected Populations of Polar Bears in the Canadian Arctic, says that if the average weight of polar bears in the Western Hudson Bay continues to decline and the climate continues to warm, “most will stop producing cubs within the next 20 to 30 years.”

It says the reason more polar bears are now being seen in the Western Hudson Bay is that “they are hungry and not that their population is increasing.” Aerial surveys of polar bears in the Western Hudson Bay show that bears numbered about 950 in 2004 – down from 1,200 in 1989, a 22 per cent drop.

In the Foxe Basin, there’s not as much detailed information about the population, although the ice breakup has been occurring earlier and earlier.

The size of the population was estimated to be 2,100 in 1996 and 2,300 in 2005, but, says the paper, the future impact of climate change was not considered before the GN granted a nine per cent increase in the quota.

In Baffin Bay, there’s also a trend to early ice breakup. At the same time, two times more than the number that was considered sustainable in 1997 are now hunted.

“Greenland hunters are likely to take 80 to 100 polar bears per year, which when added to the current quota of 105 for Nunavut, results in an annual harvest of approximately 200 bears per year or at least double the level that was estimated in 1997.”

In the Davis Strait, where the quota was increased by 12, the paper says “it seems likely that the population is no longer increasing and could, in time, be negatively affected by the trends toward less sea ice, earlier breakup, and possibly a decline in the total population of harp seals if the climate continues to warm as is predicted.”

If fewer bear-human conflicts have been noted along the eastern side Hudson Bay, the scientists suggest that this is due to the location of communities.

Complete scientific information is only available for the western Hudson Bay, where the decline in numbers, size, and survival of cubs has been documented.

But the paper concludes “if the climate continues to warm… polar bears in all five populations discussed in this paper will be stressed and are likely to decline in numbers, probably significantly so.”

And as the numbers decline, problem polar bears will also increase, creating that illusion of greater numbers.

The paper suggests the potential effects of global warming be integrated into management and conservation of the polar bear species.

However, Nunavut government’s wildlife boss, Mitch Taylor, has taken an opposite view. Taylor maintains climate change is not pushing polar bears to the brink of extinction and that polar bears and people will adapt to a warmer Arctic.