MCGREW, Neb. (AP) — Several volunteers have spent two days assessing the health of Nebraska’s bighorn sheep population.

Nebraska Game and Parks staff members and volunteers created an inspection station Saturday in the Williams Gap Wildlife Management Area southwest of McGrew.

The sheep were captured with nets, blindfolded, placed in slings before getting a ride from a helicopter to the inspection site. The animals underwent a 28-step inspection, which included health checks and sampling, as well as being fitted with tracking collars. The wild sheep were inspected for about 10 minutes before being released back into the wild.

Nebraska Game and Parks staff, the U.S. Department of Agriculture, zoos in Omaha and Lincoln, area veterinarians, Chadron State College and South Dakota State University assisted with the evaluations.

“We have a conglomerate of folks, about 50 people,” said Todd Nordeen, Game and Parks’ big game research and disease program manager, who directed the weekend operations in Williams Gap and Fort Robinson. “We can process them quickly with that much help.”

Nebraska’s herds are at risk of being thinned by pasteurella pneumonia and other respiratory diseases.

“We’re trying to track the progression of the disease pathogen,” Nordeen said. “We’re doing better here in the Wildcat Hills than in the Pine Ridge.”

Experts believe pasteurella pneumonia killed half of the animals in the Pine Ridge herds in 2005 and 2007.

Sheep were reintroduced to the area nearly four decades ago after native herds were decimated by hunting. Western Nebraska now has several hundred sheep that can occasionally be viewed on public lands or from county roads.