Monday, December 10, 2007
Polar Bear Facts
Polar bears have become an icon of the dangers of anthropomorphic global warming. Global warming could cause polar bears to go extinct by the end of the century by eroding the sea ice that sustains them. The fact that there are more of the bears now than at any time in the last hundred years doesn't seem to matter. They are photogenic animals and most of the photos being circulated are cute family portraits. Here is a photo of a bear doing what they were born to do, kill seals and eat the skin and blubber.
The estimates of the number of living bears varies between 20,000 and 40,000. Canada has the lion's share of the bears, about 60% of the World population. Most of the Canadian bears live in Nunavut, the newest Canadian Territory. The World Wildlife Fund lists the 19 populations of polar bears here.Below is the map of those 19 areas. There is a noticeable asymmetry caused by the Gulf Stream; that is, there are bears in Ontario at 50 degrees latitude but over in Europe there are no bears south of the Arctic Circle, none even in northern Norway, which is above 70 degrees latitude.
Hudson Bay has three distinct bear populations--the Western Hudson Bay population which is about 1/3 in Manitoba and 2/3 in Nunavut; the South Hudson Bay, which is mainly Ontario with a little Manitoba and some Quebec (in the northern third of Quebec called Nunavik); and then there is the Foxe Basin to the north all in Nunavut. Notice too the population to the east, in the Davis Strait area, which includes some of Nunavik, Labrador, Baffin Island in Nunavut and some of Western Greenland.
Here is what the Canadian government says about the Western Hudson Bay population, that it has decreased by 22%, from about 1,200 in 1987 to less than 950 in 2004. That's not what some residents of the area say and not what the native population says. Inuit also argue the bear population is on the rise along Western Hudson Bay, in sharp contrast to the Canadian Wildlife Service, which projects a 22% decline in bear numbers. The Inuit say the government estimators fly over an area and miss a lot of bears, while they, on the other hand, are actually on the ice and see all the bears that are there. Except for their use of snow mobiles, that makes some sense. So I believe the Inuit and Churchill residents, not the scientists.
Here's some support for that belief. The South Hudson Bay population is stable. The Foxe Basin population is stable. There was not enough information to make a call about the Davis Strait, but now it turns out that the Davis Strait bear numbers have been rising, fast, from about 800 in the mid-1980s to 2,100 now. The scientists admit that if global warming is a cause of the decline in the bear numbers, one would expect it in the south where it should be "the first to show negative effects associated with climate warming and consequent loss of sea ice."
So I'm going to propose a different reason for the supposed decline in polar populations and it is an old one, indeed, it is the same one that led to a 5,000 bear World population earlier in the 20th Century, hunting. Nunavut allows at least 500 bear kills a year. Other Canadian places, like Nunavik, have no restrictions on the number of bears killed (by Inuit). There are no restrictions on Inuit kills of polar bears in Greenland. Who knows what goes on in Siberia. (A reader pointed out that Manitoba does not allow hunting so the Churchill population would not be decreased thereby. To him or her I respond, less than half of the Western Hudson Bay population is in Manitoba and it is disputed whether the population is decreasing). We'll see how the bear populations fare in the next few years, just as we watch, through the wonder of weather satellites and Mr. Gore's internet, the rise and fall of sea ice almost in real time.