Beetle infestations have killed off most of the whitebark pines in the eastern part of Yellowstone National Park and the Absaroka Mountains, as a Natural Resources Defense Council aerial study shows significantly more damage to the pine population that previously though -- giving fuel for the pines to be listed as an Endangered Species.

Whitebark pine play an important role in the Greater Yellowstone Ecosystem. The trees, which grow in harsh, high-altitude conditions, provide shelter and food for small mammals and birds. Their pine nuts are a crucial source of food for grizzly bears exiting hibernation in the spring.

The cause of the whitebark-pine problems? Scientists say global warming. As the mountain pine beetle proliferates, it targets the whitebark pine. Normally this wouldn't be a problem, as the beetles would be killed off in the winter. Since winters are demonstrably warmer in the upper altitudes of the Greater Yellowstone Ecosystem, the beetles aren't killed off. They weaken whitebark pines and leave them open to damage from blister rust.

The damage is real: the Natural Resources Defense Council study (done in conjunction with Ecoflight) estimates that 85 percent of the forests in the Greater Yellowstone Ecosystem are already either wiped out or damaged. Only 5 percent showed no signs of damage.

The report served as the cornerstone of the move to declare the whitebark pine an Endangered Species, now currently under consideration by the US Fish and Wildlife Service.

You can read the full report here.

RELATED STORIES: Yellowstone's Whitebark Pine May Be Declared an Endangered Species

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