MURPHY, Idaho -- The largest-ever project in the U.S. to remove thousands of juniper trees to help imperiled sage grouse has started in Idaho.
Junipers provide perches for raptors that attack and kill sage grouse. Junipers also force out sagebrush and other plants that produce bugs that sage grouse eat. Sage grouse also feed on the sagebrush during the winter.
Overall, sage grouse numbers have dwindled from an estimated 16 million before European settlement of the West to no more than 500,000 today in 11 western states.
The project that began last spring in Idaho aims to remove junipers on 965 square miles (2,500 square kilometers) of state and federal land.
"What we're doing here is turning the sagebrush steppe habitat that's marginal nesting habitat for grouse into immediate, quality nesting habitat for grouse," said Josh White of the U.S. Fish and Wildlife Service.
Sage grouse are chicken-sized, ground-dwelling birds considered an indicator species for the health of vast sagebrush landscapes in the West that support some 350 species of wildlife. Experts generally attribute their decline to road construction, development and oil and gas leasing.
The project that is estimated to take 10 to 15 years could become a template for other western states as junipers have expanded because of fire-suppression efforts. Juniper-removal projects have been carried out before, but not on this scale.
Environmental groups fought the Idaho project contending it was being driven by grazing interests.
"When you remove vegetation and disturb the ground, that's when invasive species come in," said Scott Lake of Western Watersheds Project, citing fire-prone cheatgrass in particular.
But federal officials gave the final approval earlier this year. Some cutting was done in the spring, and the pace picked up in the last three weeks with crews of 50 to 60 workers with chain saws cutting down junipers.
"Historically, fire would have kept these trees in check," said Ben Sitz of the U.S. Bureau of Land Management. "We're trying to preserve the diversity we have."
The project is designed around sage grouse breeding grounds, called leks, where males perform elaborate rituals. The project area contains numerous leks, both active and abandoned as junipers moved in.
Radio-telemetry on sage grouse has determined that leks ideally have no or few trees within a 6-mile (9.5-kilometer) radius, which gives nesting sage grouse hens the best chance to raise their chicks. That means each lek needs about 115 square miles (295 square kilometers) of treeless sagebrush. The project aims to cut down junipers within that distance of leks.
Junipers are being cut where sagebrush still covers most of the ground. Thicker stands of junipers that have pushed out sagebrush are being left as those areas would take decades to become suitable sage grouse habitat. But those thicker stands could be targeted for a future project.
Rancher and Owyhee County Commissioner Jerry Hoagland said ranchers want the junipers removed to improve cattle grazing.
Ranchers have "been recognizing the effects of the junipers over the years," he said, noting cut areas have led to more water. "We're getting lots and lots of stream flows running again that haven't run for 70, 80 years."
Only a small percentage of the area involves state-owned land, but not treating it could leave thousands of acres of federal public land unsuitable for sage grouse. "We're all working together to try to find ways to achieve mutually agreeable outcomes," said Dustin Miller, director of the Idaho Department of Lands.