Polar bear scares
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Neil Seeman, National Post (Canada)
June 22, 2002
Graceful even in sloth, the polar bear is the coolest kid on the Arctic block. He's got the girls, the Coke commercials, his mug on the two-dollar coin. Why can't the whiskered walrus catch the same breaks?
Everyone loves the polar bear; no one wants to see him get hurt. And so he has become a pawn in the big green propaganda machine. On its Web site, which includes satellite tracking of two female bears (Louise and Gro) as they roam the ice pack in search of prey, the World Wildlife Fund announces: "The polar bear is under threat. From toxic chemicals, from oil exploration and production, from hunting, and from climate change."
But we needn't fret or fume about the furry giants. Polar bears around the Beaufort Sea are thriving, possibly even reaching historic numbers, according to research by Steven Amstrup of the U.S. Geological Survey Biological Science Center. In a paper published last year in the Journal of Agricultural, Biological and Environmental Statistics, Mr. Amstrup estimates the number of polar bears between Barrow, Alaska, on the west and the Tuktoyaktuk Peninsula in the east has increased by more than 2% a year for 30 years.
"I believe in what the scientists are saying," says Charlie Brower, chairman of the Alaska Nanuuq Commission. (Nanuuq means "polar bear" in Inupiaq.) "But I don't know why. All I know is their numbers are growing." Villagers along the North Slope patrol the perimeters of settlements in the fall and early winter to fend off the growing army of bears.
Mr. Amstrup and other polar bear researchers speculate that the population spurt may be due to the near-complete ban on polar bear hunting for the last three decades. Two years ago, the United States and Russia signed a treaty to govern the take of polar bears off Alaska's west and northwest coasts.
But if polar bears are in such great shape, why do environmentalists keep firing off tear-stained press releases? "Polar bears victims of inaction on global warming," said the WWF in May. The WWF report, "Polar Bears at Risk," points to evidence that global warming is decimating polar bears in Hudson Bay. The report says sea ice is thawing earlier in the spring, which means many bears spend long periods off the ice and trapped on land, where they find it hard to feed, while young bears are dying in dens that melt and collapse. By the end of the summer the adults have turned scrawny, impairing their ability to reproduce.
It's a good story, but a dubious one. The WWF, Greenpeace and other environmentalists hang their hat on a 1999 study by Canadian scientists Ian Stirling, Nicholas Lunn and John Iacozza for the Canadian Wildlife Service. Yet the study's trend data, which attempted to show ever-shorter ice periods in western Hudson Bay, were not statistically significant -- i.e., they could be explained by random chance or measurement error alone.
To be sure, the researchers did find evidence to suggest that some bears in one region of the Hudson were not as fat as they once had been. (This could spell the bears' extinction, reported the CBC in an earnest documentary, Skinny Bears.) But bears in another region were doing just fine. Nor did this study report on any declines in litter size, litter survival or in the actual numbers of polar bears seen throughout the study area. In fact, the study showed the survival rates of cubs during the first six months after leaving their mother's den improved dramatically from the late 1980s (50%) to the mid-to-late 1990s (70% to 80%).
Even if global warming were progressively broiling the sea ice, there would be little reason to worry too much about the polar bear. For warmer temperatures would also melt the snow over the lairs of the bears' prey, the ringed seal, making capture easier. And if the seal couldn't be caught, there are other prey: beluga whales, walruses, narwhals and bowhead whales and, when there is no other food, reindeer, small rodents, seabirds, ducks, fish, eggs and vegetation. Like other animals, polar bears adapt readily to changes in their environment; they can swim underwater for miles before pausing to rest, migrating to locations where ice shelves remain should their own disappear.
Even though the bears may be safe and happy, the drums of doom beat on. Drawing on the Canadian Wildlife Service study, The Province in Vancouver last year reported that "polar bears ... are taking a beating from climate change." Yet, to make this claim, the researchers only provided correlational evidence linking rising temperatures to the ice floe disturbances.
Every Christmas, the World Wildlife Fund encourages people to "adopt a polar bear" to save it from the global-warming apocalypse. Whenever one year's litter is smaller than the previous year's, environmentalists get in a snit. If it's not global warming, then PCBs are to blame. (No causal link is ever shown between PCBs and bears' health problems). Meanwhile, sporadic regional fluctuations in litter size are more easily explained by limits in the available food supply than by any gloom wrought by PCBs or ice floes.
Should we be concerned about the ice floes? Every dire scenario about the polar bear (and pretty much everything else to do with global warming) assumes that the ice shelf is crumbling. Yet much of the evidence for Arctic meltdown is limited or contradictory. Two years ago, the U.S. Global Change Research Program reported the average thickness in Arctic ice had fallen substantially over several decades. Then last year, a Swedish researcher re-examined ice data culled from U.S. submarine measurements and reported in Geophysical Research Letters that there had been no thinning of ice in the Arctic Sea for the last dozen years. Then, a Canadian arctic researcher, Greg Holloway, said the reason for the discrepancy was that Arctic ice oscillates with the winds in 50-year cycles, something the other research had failed to consider. All of which led Frederick Seitz, past president of the National Academy of Sciences, to conclude that Arctic ice studies are "filled with uncertainty."
Much of the "evidence" of ice collapse actually comes from the other Pole, where there are no polar bears. In recent months several icebergs, some as big as Prince Edward Island, have plunged into the ocean around the Antarctic. ABC's Good Morning America suggested this was "more proof of global warming." But the only reason people had never seen so much ice erode is because the required satellite technology wasn't available before.
"The icebergs that have calved in the last couple of months probably don't have much to do with global warming," explained Ted Scambos of the National Snow and Ice Data Center, which had detected the collapse of the biggest block of ice. "It is part of a pattern of growth and retreat that is more or less normal." Meanwhile, Jay Zwally of the NASA Goddard Space Flight Center reports in the June issue of the Journal of Geophysical Research - Oceans that the amount of sea ice surrounding Antarctica has increased about 1% per year over the last 20 years. That hasn't made news.
Incredibly, many in the media have gone out of their way to invent evidence of ice depletion. In August, 2000, a Russian icebreaker, Yamal, shepherded a few scientists to the Arctic Ocean. When they got to the North Pole they happened upon an expanse of open water. "Santa's workshop underwater," reported ABC News. "The last time scientists can be certain the Pole was awash in water was more than 50 million years ago," proclaimed The New York Times in a bewildering front-page article entitled, "The North Pole is melting." Ten days later, the Times retracted the story. (Yes, there was water at the Pole, the newspaper said, but there often is.)
How can this happen? Journalists assume (perhaps correctly) that people are more intrigued by bad news than good. In the 1970s, the international media frightened people into thinking icebergs were swelling, not shrinking. The New York Times declared that there were "many signs pointing to the possibility that the Earth may be headed for another ice age." Since that time, the polar bear population in Alaska has doubled.
