Sunday Forum / Introducing ... the pizzly bear
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A new kind of bear was discovered three years ago in the remote arctic. That should have been good news in a world in which species are disappearing at an alarming rate. Instead it was a signal that nature is suffering from heatstroke, caused by greenhouse-gas pollution from oil, coal and other fossil fuels warming the planet faster and hotter than species can cope with.
The new bear was called a pizzly, because, as its name implies, it was born from a polar bear mother and grizzly bear father. As long as humans have walked the planet, polar bears and grizzly bears have lived apart; but, as the planet heats up, grizzly bears are waking up from their winter nap earlier, and the icy home of polar bears is melting out from under them. Which means the two bears are sharing habitat -- and apparently some romance.
The problem with pizzlies is that they're nature's version of a dead-end. They're ill-suited to survive as polar or grizzly bears, and the only one known is already dead.
As a paleoecologist, I have spent my career trying to understand how animals and plants adapt to change. Pizzlies are a sign of nature in peril.
That's a practical problem because nature gives us "ecosystem services" we rely on, like clean water, food and medicines, worth trillions of dollars annually. But it's an emotional problem, too, because most people want to keep nature alive -- it simply makes us feel good, and we want our children to find the same pleasures in it that we do.
Probably for that second reason more than any other, nations have set aside 12 percent of the Earth's surface as some sort of nature reserve. The pizzly raises a fundamental challenge to what we thought we knew about how to protect the natural world.
As global warming causes dramatic local climate changes, even species in remote areas will need to rapidly adjust to brand new climates or move. If they cannot, they will perish.
Warming has already reduced populations of many kinds of animals in crown-jewel nature preserves like Yellowstone and Yosemite parks and Africa's Kruger Park, and caused extinctions of many Central American amphibians. Even Earth's biggest biodiversity bank, rainforests, seems likely to suffer vast losses of species under new climate regimes.
For decades a "one-stop-shopping" approach to nature conservation worked: save enough wild land and you automatically save all the species within it, their interactions and the beauty we can find in nature. In the Age of Global Warming, that one-stop shopping approach will likely fail.
To save endangered species in a warming world we may be forced to move species trapped in places that are changing too quickly for them to survive. Already, conservation scientists are discussing plans for "assisted migrations," in a Noah's Ark approach.
Prevailing ecological wisdom says introduced species do more harm than good; yet, what is the right choice when moving a species would save it from extinction?
Perhaps an even bigger conundrum is that moving species around is exactly the opposite of what is required to save the "real thing" of nature -- places where the land, animals and plants evolve without a heavy human hand.
Resolving this conflict will require two separate-but-equal kinds of nature reserves. "Species reserves" will be the Noah's Arks that save certain species, even when the feeling of the wild has to be sacrificed. "Wildland reserves" will be places where we simply let nature take its course in this new age, even as we watch individual species within them disappear and other species find their way in.
Redefining our concept of nature reserves and moving species about to save them may seem odd and will no doubt be controversial, just as slowing global warming itself has been. But the other choice is to do nothing and watch the problem with pizzlies play out again and again, until nature as we know it disappears.
First Published September 13, 2009 12:00 am