What Polar Bear Decline?

Washington, D.C., August 15, 2011 — It’s about those polar bears. You know, the ones endangered by global warming turning the Arctic into Florida, the poster predators of man’s inhumanity to the Earth. Those cute figures who have graced Coca-Cola ads and memorabilia for decades.

Well, maybe they aren’t that endangered after all. An essay by zoologist and science writer Matt Ridley in London’s Spectator newspaper last week discusses the issue of the lovable top predators of the North. Also, it turns out that a wildlife biologist who sparked a tide of concern over the plight of the white bears of the ice may have been faking it when he reported spotting dead polar bears floating in Arctic waters in 2004.

First, to Ridley — who faced a polar bear from a tent in Norway’s Spitzbergen Island in the summer of 1978. “Today,” he writes, “bears are now far more common in Spitzbergen and the other islands of Svalbard. They are more common all over the Arctic than 33 years ago.” In 1966, the International Union for the Conservation of Nature estimated the world’s population of polar bears at 10,000. In 2006, the IUCN’s estimate was 20,000-25,000 and the monitoring group says there has been no decline since then.

In large part, that’s due to an end to shooting and trapping bears. A 1973 international agreement ended sport and commercial hunting of the bears (no doubt driving up the price of polar bear rugs considerably). Another component of the population figures is that we just don’t know a heck of a lot about long-term bear population changes. They are long-lived and slow to breed, as the National Oceanic and Atmospheric Administration notes. Coordinated monitoring of the population of the mammals that reaches across the entire Arctic only started in the late 1960s.

Then there are those four dead polar bears, which Al Gore fretted over in his An Inconvenient Truth film, presumably drowned in open water trying to move from one vanishing ice flow to another. “But polar bears often swim long distances — one was recorded swimming 400 miles,” writes Ridley, “and nobody knows how unusual it was for four to get caught in a storm and drown.”

If those drowned bears were real. National Public Radio reported last week that the wildlife biologist who reported seeing the drowned bears in 2004 — Charles Monnett — is “under investigation by the Department of Interior’s Office of Inspector General.” The New York Times reported the week before that Monnett had been “placed on administrative leave pending an internal investigation into ‘integrity issues’, according to a copy of a letter posted online by the watchdog group Public Employees for Environmental Responsibility.”

Writes Ridley, “The polar bear is a specialist seal-eating predator (so it is little wonder that it goes for other elongated, six-foot mammals when hungry). It occupies a specific niche: the ice edge. It cannot survive on unbroken Arctic sea ice, because seals are not found there. Nor can it survive on ice-free seas because it cannot kill seals in open water.”

If global warming causes the ice-free season to be longer, notes Ridley, the bears at their southern-most range might die out. On the other hand, “areas further north, currently too solidly frozen for seals, will become more hospitable to bears.”

Those most alarmed by the prospect of a warmer climate claim that 2007 saw the greatest Arctic ice retreat on record. But the record only goes back to 1979. The 1920s and 1930s were surely warmer. Ridley observes that there have been plenty of previous warm periods, all the way back to the Holocene Optimum, some 5,000 years ago. “Polar bears certainly survived such warmer spells,” he concludes, “presumably by ranging somewhat further north. Indeed, fossils suggest that polar bears already existed in their current form from during the last interglacial period 120,000 years ago, when the Arctic was almost certainly wholly free of ice in late summer.”