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The federal government says whitebark pines face an imminent risk of extinction. The trees are critical to the high mountain ecosystems in Yellowstone National Park and across the Northern Rockies. A ravenous beetle, a fungus and climate change are largely to blame.
But NPR's Elizabeth Shogren reports, the government says it can't afford to put them on the endangered species list.
ELIZABETH SHOGREN: Scientist Jesse Logan was the first one to predict that global warming would allow a major outbreak of mountain pine beetles in whitebarks. But last week when he hiked near the northwest corner of Yellowstone, he was astounded. Where he expected to find green trees mixed in with dead ones, every mature tree was a dead gray skeleton.
Dr. JESSE LOGAN (Scientist): You'd think I get used to it, but it's always a shock when you go into these beautiful, vibrant forests that are no more.
SHOGREN: Logan says then he noticed something that raised his hopes.
Dr. LOGAN: We saw from a distance this really nice little grove of whitebark that are almost cone-bearing age. And, oh, that's cool. Here's the future forest.
SHOGREN: But when he reached them, he found their branches swollen with the telltale sores of white pine blister rust. That disease will prevent those young trees from ever bearing cones and eventually kill them. These combined threats, blister rust and mountain pine beetle, persuaded federal biologist Amy Nicholas that whitebark pine qualify for endangered species list protection.
Dr. AMY NICHOLAS (Biologist, U.S. Fish and Wildlife Service): Both of these threats act to severely decrease seed cone production. And when there's no seeds left, you're going to lose your species.
SHOGREN: Do you think it's a foregone conclusion that this tree will go extinct?
Dr. NICHOLAS: Yeah, I do. Or at the very least, there might still be some trees scattered here and there and left on the landscape, but the tree is functionally, probably going to be extinct.
SHOGREN: But instead of putting whitebarks on the endangered species list, her agency added them to a list of candidate species. Nicholas says the federal Fish and Wildlife Service doesn't have the money or resources to protect the trees. Experts say what's so tragic about the tree's fate is they literally created the habitat in the high mountains, and they provide lots of services to nature and people.
They grow at high altitudes where no other trees can survive. Their nutritious seeds feed grizzly bears and lots of other animals. And shade from their broad canopies retains the snow in the mountains longer, keeping streams running fuller and cooler in the summer.
Ms. DIANA SIX (Forest Entomology and Pathology, University of Montana): So that impacts everything. That impacts us. It impacts agriculture. It impacts fisheries.
SHOGREN: University of Montana Forest pathologist Diana Six says the whitebark die-off shows how climate change can set off chain reactions that radically alter ecosystems. The weather on the high mountains where whitebark grow used to be too frigid for mountain pine beetles, but warming temperatures have allowed an outbreak to reach epic scale.
Ms. SIX: It's hard to see something so spectacular and so important decline. It really hits you right to your core.
SHOGREN: Six says, in the high elevations of Yellowstone and Grand Teton, what she calls ghost forests - the gray skeletons of whitebarks - will stand for a century or more to remind visitors of the vibrant habitat that once was.
Elizabeth Shogren, NPR News. Transcript provided by NPR, Copyright NPR.
