Melting Ice Increasing the Chance of Polar Bear-Human Meet-Ups


Image credit: Alastair Rae/Flickr

In Nunavut, polar bears are wandering into towns, chasing children, poaching food from caches, and generally putting pressure on the people who call Northern Canada home. The increased instance of human-bear interactions, people in this region claim, is a sure sign that the polar bear population is increasing.

However, research suggests that a decreasing habitat is forcing stressed bears into territory they once left for humans.Biologists working with the U.S. Fish and Wildlife Service in Anchorage, Alaska, have looked at 27 years of data from the U.S. Government Minerals Management Services. The trend that seems to emerge is that a decreasing habitat is related to an increase in polar bear sightings.

Between 1979 and 1987, 138 bears were spotted in the southern Beaufort Sea region of Alaska. This number increased dramatically, however, to 271 sightings between 1988 and 1996, and finally 468 sightings between 1997 and 2005. Moreover, the data shows that between 1979 and 1987, 12% of sightings were associated with no-ice conditions but between 1997 and 2005 90% of sightings were associated with no ice.


Image credit: irishwildcat/Flickr

The conclusion, that the loss of sea ice—the polar bear's natural and preferred habitat—forces them onto dry land and closer to human habitation, seems obvious. Researchers were quick to point out, however, that this correlation is not conclusive because the data set used was compiled to track bowhead whale migration routes, not polar bears.

Still, Karyn Rode, a polar bear biologist who led the study, said that:

Our results do suggest that bears that use the nearshore area are more likely to occur on land in recent years because their preferred habitat, sea ice, is unavailable.

She went on to say that the data her team used is one of the only sets available that covers such a long timeframe and then added that "it shows there has been a shift in [polar bear] habitat use."

The Situation in Nunavut

Of course, the Beaufort Sea is not Nunavut. For one, there are more people, and more polar bears, who call the Canadian province home. Of the estimated 22,000 to 25,000 polar bears in the world, about one third are thought to live in Canada—and most of those in Nunavut. The human population too, while not tremendous, is larger than that of the Beaufort Sea area of Alaska—about 32,183 people in Nunavut as opposed to 7,385 in all of North Slope county, Alaska.

Some things, however, are very similar. Nunavut, like northern Alaska, has been consistently losing sea ice, especially multi-year ice which provides a thicker and more stable platform for bear hunting and denning.

Still, not everyone agrees with the correlation. Paul Irngaut, a wildlife adviser with Nunavut Tunngavik Inc., a company that has set up hot-lines residents can use to report bear sightings, commented that:

People from the South only hear one side of the story, which is from polar bear biologists or scientists who are using predictions, using computer simulations and we don't agree with that.

He believes, as many of his Inuit neighbors do, that climate change is actually helping polar bears by thinning ice and making hunting in the water easier.

Their position, however, is becoming less common around the world. As the only country to still allow sport hunting of polar bears, the Canadian government is facing increasing pressure, notably from the U.S. Department of Fish and Wildlife, to ban the annual harvest.

Meanwhile, the hotline phones keep ringing and, with each report, seem to confirm what is already known: Not that polar bear populations are increasing, but that the situation in the planet's northern latitudes is more complex and dire than it immediately appears.

Read more about polar bears:
Global Warming Not the Only Thing Threatening Polar Bears
Starving Polar Bears Turning to Cannibalism
Polar Bears on Thin Ice
US Department of Interior Lists Polar Bear As Threatened

Tags: Animals | Global Climate Change | Global Warming Effects

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