STEVE INSKEEP, host:
All right, the federal government is expected to decide soon about whether to put the polar bear on the endangered species list. It would be the first species to be listed because of climate change.
NPR's Elizabeth Shogren reports that the nature of the threat gives polar bear lovers around the globe an opportunity to help save them.
ELIZABETH SHOGREN: For most people the only place they'll ever get to see a polar bear is in a zoo. At the Pittsburgh Zoo, you can walk through a glass tunnel in the middle of the bear's swimming pool. That's what Amy and Brian Wilding(ph) are doing with their toddler Tria(ph).
Ms. AMY WILDING: Tria, look at that. Look at them diving. That's just amazing.
SHOGREN: Koda, one of the twin polar bear brothers who live at the zoo swims right past them.
Ms. WILDING: He likes watching them swim. That's probably the most amazing thing is when they're right above, you think you're close to them, you put your hand up there and you're really - like how many feet away from a gigantic bear. But they don't look dangerous. They look like such a big, furry bear you can play with. It's wonderful.
SHOGREN: Koda and his brother Nuka are three years old and already weigh more than 600 pounds. As the brothers wrestle in the water above his head, keeper Mark McDonough says they're also powerful carnivores.
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SHOGREN: McDonough takes me behind the scenes to meet the third - even bigger polar bear, Marty. He's interested when a fluffy mic is pointed in his direction. When he gets close to the door leading to the exhibit, where the twins are, they sniff and bang up against the door.
Zoo's curator, Henry Kacprzyk, says the polar bears are a huge draw for visitors.
Mr. HENRY KACPRZYK (Curator, Pittsburgh Zoo & PPG Aquarium): And while they're here, we're trying to educate people about the bears and what you can do to help these animals. A lot of people don't realize, you know, the Arctic is really in for some bad times.
SHOGREN: Scientists predict that two-thirds of the world's polar bears will disappear by the middle of the century. That's because the summertime sea ice is rapidly melting.
Dr. ROSA MEEHAN (Supervisor, U.S. Fish and Wildlife Service, Alaska) As the ice retreats and retreats extremely far north as it has in a past couple of years, the bears simply have less places to be.
SHOGREN: Rosa Meehan heads the marine mammal program for the U.S. Fish and Wildlife Service in Alaska. She says many more bears are ending up on land but land isn't the best place for them. Their ideal habitat is floating slabs of ice, which teemed with fish and the bear's favorite meal - seals. Meehan says more time on land increases the chance for polar bears to encounter people. That can be deadly for both the people and the bears.
Dr. MEEHAN: Polar bears are curious. If there's a new smell, new activity, new noise — it might be something to eat — and so they'll just go over to investigate.
SHOGREN: So there's also a risk to polar bears from expanding oil production. Next month, the federal government plans to sell off-shore leases for 30 million acres of the Chukchi Sea, where about one-tenth of the world's polar bears live.
But Meehan says the biggest threat facing the polar bear is global warming. And unfortunately, she says, for the next few decades, no matter what people do to counteract climate change, the summer sea ice will continue to decline dramatically.
Dr. MEEHAN: Even if we all stop driving our cars today, we're not going to have a lot of change in the near term, but after that it will start to have changes.
SHOGREN: So she says, cutting energy use and recycling today will improve polar bears chances over the long term.
Dr. MEEHAN: We want to do everything we can to essentially help the polar bears through this next very difficult period so that polar bears persist, and that when things turn around as a result of society making changes, the polar bears will still be in the environment and be able to take advantage of, hopefully, a rebuilding of the sea ice and a rebuilding of the ice ecosystem.
SHOGREN: Back at the zoo, some visitors say they've already gotten the message.
Jim Gessler(ph) has been coming here to see the polar bears here since he was a kid. Concern about their fate has pushed him to do what he can about climate change.
Mr. JIM GESSLER: I'm turning off lights when I leave the room. I don't have a car anymore.
SHOGREN: What do you do for transportation?
Mr. GESSLER: Public transportation. Anything we can do.
SHOGREN: His 22-year-old daughter, Anne(ph), says she's given up meat.
Ms. ANNE GESSLER: How much energy it takes to produce a hamburger is really distressing.
SHOGREN: She says many people think you have to buy something expensive, like a hybrid car to help the environment.
Ms. GESSLER: But if you just make small changes in your lifestyle, that's a lot more beneficial.
SHOGREN: But polar bear biologists say it will take more than individual actions: saving the polar bears will require governments around the globe to make major efforts to cut greenhouse gas pollution.
Elizabeth Shogren, NPR News.