BOISE, Idaho (AP) — 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 Idaho Statesman reports that the study released earlier this month found 99 percent of active breeding sites are in areas with no more than 3 percent of the land disturbed by roads, power lines, pipelines and communication towers. Agency biologist Steve Knicks says the study found areas with even low levels of human activity didn't have sage grouse breeding sites.

Scientists analyzed information surrounding 3,000 active breeding areas with a 355,000-square-mile area of the sage grouse's historic range. The U.S. Fish and Wildlife Service is reviewing whether to list the sage grouse as a threatened species.