Nearly every headline about the U.S. government’s new report on polar bears echoes gloom and doom. One after another, they range from speculation of “the brink of extinction” to predictions of a “population crash” that will likely begin in about 10 years. One after another, they despair: “It may be even worse for the polar bears than previously thought.”
Unfortunately, these headlines aren’t wrong. But they do ignore a critical caveat: We can, at least slightly, improve the polar bear prognosis.
“It’s unfortunate that [extinction] is the message that pervades all this,” Todd Atwood, a research wildlife biologist at the U.S. Geological Survey, told ThinkProgress. “Yes, that’s the most likely scenario if nothing happens on the mitigation front. But the subtext is that we have opportunities.”
Atwood is the lead author of this new report that seemingly predicts the polar bear’s hopeless demise. But the report, released Friday by the Fish and Wildlife Service, is actually called a “Recovery Plan” — a blueprint that the government believes “will contribute to the conservation and recovery of polar bears.” It’s a five-year, nearly $13 million plan, and it identifies ways the U.S. can create the best possible outcome for the species, which was listed as threatened in 2008.
The short version of the plan is that it won’t be easy. Even with enormous efforts, polar bears will still face high risk of being wiped out of certain areas. And that’s because the number one threat to polar bears’ continued survival is human-caused climate change.
According to the report, the “the primary threat to polar bears” is the decline of their habitat, which is sea ice. The second place threat is decreased access to marine mammal prey, which the bears get by hunting — on sea ice. Worldwide, sea ice has decreased by about 12 percent per decade since the 1970s, according to the National Snow and Ice Data Center. The melt is fueled by climate change, a phenomenon caused by emissions of carbon dioxide and other greenhouse gases.
CREDIT: Washington Post Graphic
So what to do? Obviously if climate change is the main culprit, that’s what needs to be stopped. But that requires swift and decisive action on an international level. Jenifer Kohout, the Fish and Wildlife Service’s regional program manager, admitted as much in comments reported by the Associated Press. In essence, Kohout said, all we can do is wait. “In the meantime,” she said, “the Fish and Wildlife Service and its partners are committed to doing everything within our control to give the bears a chance to survive.”
At first glance, it can seem like there’s not a huge difference between doing nothing about climate change and doing something, at least when it comes to polar bears. Atwood explained that if emissions are allowed to increase as usual (a scenario referred to in the science community as “RCP 8.5”) then there is a “substantial likelihood” that polar bears will be left in a “severely decreased” state. And if the world is able to stabilize its emissions and not increase them (the “RCP 4.5” scenario) then there is still a “substantial likelihood” that polar bears will be left in a “severely decreased” state.
However, Atwood explained, there is an important differentiation between the two. If we allow emissions to increase as usual, there is an approximately 75 percent chance of “severely decreased” polar bear populations in most regions. But if we can stabilize emissions, the likelihood of “severely decreased” populations decreases by about 25 percent. That means there would only be an approximately 50 percent chance that polar bear populations would severely decrease. The remaining 50 percent would be spread out between the chance that polar bear populations are decreased, or stay the same.
Why is that important? According to Atwood, there’s a huge difference between “decreased” polar bear populations and “severely decreased” populations.
“When we’re talking about just ‘decreased,’ we’re talking about animals that are still present in the population in a region in a meaningful way — that they’re not on the verge of being highly vulnerable to events that would lead to their localized extirpation,” he said, referring to events like severe weather or disease outbreak that could wipe out remaining animals. “A decreased outcome is not necessarily vulnerable to extirpation,” or local extinction of a species.
Of course, a decreased population is still vulnerable to threats. And in many regions, even reducing emissions to the stabilized scenario still puts polar bear populations with a dominant likelihood of being severely decreased. But, Atwood said, the stabilized emissions scenario gives us time.
“If we can adhere to the RCP 4.5 trajectory, we can forestall the transition to a greatly decreased state by about 25 years,” he said. “That gives us time, then, to perhaps innovate, and further reduce greenhouse gas emissions below the 4.5 trajectory, and also manage the other threats that are much less important than greenhouse emissions but do buy you some time.”
In other words, if emissions can be stabilized, that gives the government more time to combat threats to polar bears that aren’t climate change. Those include hunting, parasites, disease, and exposure to pollutants like oil.
One things Atwood said researchers are particularly interested in is the future threat of human-bear conflict. As the bears in some parts of the Arctic face decreases in their sea ice habitat, he said, they’re exploring coming ashore for the first time in their lives — and they’re encountering humans. Indeed, scientists have warned about increases in human-bear conflict as ice melts and hungry bears come onto land to look for food.
But right now, “the primary threat is greenhouse gas emissions,” he said. “We could stop all hunting and that’s not going to stop the decline in sea ice habitat and the decline in populations.”
If populations do decline the way they’re projected to in the business-as-usual emissions scenario, the effects will extend beyond the near-loss of a cuddly-looking creature. The Arctic, Atwood said, is the “canary in the cryosphere” — the early indicator what the rest of the Earth can expect if and when climate change worsens. Indeed, the Arctic warms approximately twice as fast than the Earth as a whole — warming that has serious implications for extreme weather, sea level rise, and permafrost melt.
“What’s happening is not going to stay in the Arctic, and not just going to affect the polar bear,” Atwood warned. “We have to look at the Arctic as an early warning system of what’s likely to come for other parts of our planet.”