BILLINGS, Mont. — Whitebark pine trees can live more than 1,000 years, but in just two decades more than a quarter of the trees that are a key food source for some grizzly bears have been killed by disease, climate change, wildfires and voracious beetles, government officials said as they planned to announce federal protections Wednesday.
The U.S. Fish and Wildlife Service will designate whitebark pine as threatened with potential extinction, according to details obtained by The Associated Press. The belated acknowledgement of the tree’s severe decline will require officials to craft a recovery plan and pursue restoration work.
Whitebark pines are found at elevations up to 12,000 feet (3,600 meters) — conditions too harsh for most tress to survive.
A nonnative fungus — white pine blister rust — has been killing whitebark pines for a century and they’ve been largely wiped out in areas. That includes the eastern edge of Yellowstone National Park, where seeds from the trees are a source of food for threatened grizzly bears.
More recently, the trees have proven vulnerable to bark beetles that have killed millions of acres of forest, and climate change that scientists say is responsible for more severe wildfire seasons.
The trees occur across 126,000 square miles (326,164 square kilometers) of land in Wyoming, Montana, Idaho, Washington, Oregon, California, Nevada and western Canada.
Wildlife officials declined to designate which forest habitats are critical to the tree’s survival, stopping short of what some environmentalists argue is needed. An estimated 88% of their habitat is federally owned, with most of that area managed by the U.S. Forest Service.
Despite the threats, whitebark pine tree populations remain resilient enough to withstand disease and other problems for decades, said Alexandra Kasdin with the U.S. Fish and Wildlife Service.
“We have found it is likely to become endangered with extinction in the foreseeable future, not that it is in danger of extinction now,” Kasdin said. “The species is still relatively widespread throughout its extensive range.”
A 2009 court ruling that restored protections for Yellowstone bears cited in part the tree’s decline, although government studies later concluded the grizzlies could find other things to eat.
That has complicated government efforts to declare grizzlies in the Yellowstone area as a recovered species that no longer needs federal protection. Grizzlies raid caches of whitebark pine cones that are hidden by squirrels and devour the seeds within the cones to fatten up for winter.
Environmentalists had petitioned the government in 1991 and again in 2008 to protect the trees. After getting sued for not taking steps to protect the pine trees, wildlife officials in 2011 acknowledged that whitebark pines needed protections but they took no immediate action, saying other species faced more immediate threats.
The protections adopted Wednesday were proposed two years ago. The final rule includes new provisions that allow members of Native American tribes to collect seeds from whitebark pine for ceremonial or traditional use.
Researchers and private groups are working with federal officials on plans to gather cones from blister rust-resistant trees, grow the seeds in greenhouses and then plant them back on the landscape.
“There’s hope here,” said Diana Tomback, a University of Colorado Denver biology professor and policy director for the Whitebark Pine Ecosystem Foundation.
“We know how to find genetic resistance to white pine blister rust and there’s a number of whitebark pine trees that have it. They will be the foundation of a planting strategy,” she said.
A draft of the restoration plan is expected early next year.
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