MISSOULA, Mont.— Conservation groups filed a lawsuit today challenging the U.S. Forest Service’s approval of a large timber sale just outside Yellowstone National Park that would destroy habitat for grizzly bears, lynx and other embattled species.

“This clearcutting project is a direct threat to grizzly bears, lynx and the entire Yellowstone ecosystem,” said Kristine Akland, Northern Rockies director and senior attorney at the Center for Biological Diversity. “We know our continued existence relies in part on preserving our planet’s remaining forests and protecting threatened species. This project is completely out of step with both those urgent needs. We’re committed to stopping this devastating project before one tree is cut.”

The South Plateau project proposes to clearcut more than 5,500 acres of pine forest on the Custer-Gallatin National Forest. The project also calls for logging on an additional 9,000 acres and bulldozing up to 56 miles of roads, many through mature forests. The Forest Service determined that the project would have “no significant impacts” on the forest ecosystem.

The agency approved the South Plateau project without identifying the locations, timing or scope of the logging units or roads. Instead, it said those decisions will be made later, without additional analysis or public involvement.

“The Greater Yellowstone ecosystem is being bulldozed to death with logging roads and clearcuts,” said Mike Garrity, executive director of the Alliance for the Wild Rockies. “It’s time to say no to destroying critical lynx, grizzly bear and whitebark pine habitat. We need to be protecting the old growth forests that sequester carbon instead of clearcutting them.”

The Center for Biological Diversity and Alliance for the Wild Rockies say that the project does not fully consider the harms and risks to grizzly bears, lynx and climate change and allows for significantly more logging and road building than is authorized by the Custer-Gallatin Forest Plan. The lawsuit also asserts that the Forest Service should have engaged in a more robust environmental analysis.