Study: Sage grouse leave breeding sites when human disturbance tops 3%

BOISE – Researchers with the U.S. Geological Survey analyzing sage grouse breeding areas say the ground-dwelling birds need sagebrush-dominated landscapes with a minimum level of human activity to thrive.

The study released earlier this month found that 99 percent of active breeding sites, called leks, are in areas with no more than 3 percent of the land disturbed by roads, power lines, pipelines and communication towers, the Idaho Statesman reported.

“We knew, from previously published science, that human activity affected sage grouse, but our results in this new research showed that most leks were even absent from areas that had very low levels of human activity,” agency biologist Steve Knick said.

Scientists analyzed information surrounding 3,000 active breeding areas within a 355,000-square-mile area of the sage grouse’s historic range. In areas around breeding sites, the study found less than 14 percent showed any human development or disturbance.

“The purpose here was not to promote one viewpoint or another,” Knick said. “What is important to sage grouse is we look at the data so when we do make decisions, we can do it with a scientific foundation.”

The U.S. Fish and Wildlife Service announced in 2010 that sage grouse across the West deserved protection under the Endangered Species Act. The agency pledged to make a final listing decision by late 2015.

Sage grouse populations have fallen 90 percent in the past century, and habitat has declined 50 percent. A sage grouse listing could restrict many human activities.

Knick’s research found that even in traditional sage grouse habitat, building a cellphone tower could cause the birds to leave the areas.

“We’re talking about a wildland species,” said Jack Connelly, a sage grouse expert with the Idaho Department of Fish and Game who was not involved in the study. “This isn’t a pheasant or a quail.”

Idaho Gov. Butch Otter’s Sage Grouse Task Force has suggested various levels of protection for habitat, including the highest levels for key sage grouse areas.

“That shouldn’t come as too much of a surprise since the governor’s plan was largely built on the recommendations of Connelly and others at our Fish and Game Department with input from key stakeholders,” said Tom Perry, Otter’s chief counsel, who has led the task force.

Under Otter’s plan, big infrastructure projects would be prohibited, with few exceptions, in core sage grouse habitat.