When we act and how may determine how quickly the species disappears. Current projections don't look good. Researchers from the U.S. Geological Survey have estimated that two-thirds of polar bears will be gone by 2050. For the Arctic ice melt to make sense, all you have to do is watch this YouTube video, from the National Oceanic and Atmospheric Administration, which shows the puny extent of sea ice in 2012 compared with the historical average.
With all that as the backdrop, feeding polar bears doesn't sound so crazy, however sad and potentially irreversible it may be. And such programs do exist for other species, Derocher said, including California condors, black bears in Washington state and brown bears in Eastern Europe.
"We're at the point where we're going to be implementing some of these scenarios in some parts of the Arctic," he said, "without doubt.
"Bears just aren't as fat as they used to be," he said, which makes them less able to live through low-sea-ice years. "It's very clear when you look at the data and when you just look at the animals. A lot of them just don't have that much gas left in their tank."
I asked Derocher what drives him. He said he's not a sentimental person -- he doesn't get attached to an individual polar bear the way he does to his golden retriever. But when you're in the Arctic and you see how much the bears are struggling, it's hard not to care about them as a group -- to want to do something to preserve their wild power.
"I'm still optimistic that humans will decide to deal with greenhouse gases in a realistic fashion," he said.
To illustrate why that's important, he pointed me to an online video that shows the death of a young polar bear cub. It's linked here but, as a Mother Jones writer put it, "Be forewarned: this is graphic and ghastly." I wouldn't watch it unless you absolutely feel the need to do so. What's more important is Derocher's reaction. For him, the video echoed his experiences in the Arctic, surveying bears that are struggling because of sea ice melt.
"When you watch that," he said, "you have to, I think, be pretty hardhearted to think that maybe humans aren't treading a little too heavily on this planet."
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