New Collars Boost Bighorn Sheep Monitoring Efforts

The Nebraska Park and Game Commission is better able to monitor the health, movements and distribution of bighorn sheep in Wildcat Hills thanks to a project completed this month.

With the help of a helicopter capture team, Game and Parks placed tracking collars on 27 sheep over two mornings, September 20 and 21.

Similar to previous efforts, the helicopter crew used a net gun to catch individual sheep, place them in a shoulder bag, and transport them back to mobile processing sites. At those locations, a team of Game and Parks employees, partners and volunteers placed collars and numbered identification tags on the animals, collected tissue samples and released them back into the wild within minutes.

While the effort may have resembled sheep-trapping efforts of the past, it had one key difference: temperature. The weather during this effort was in contrast to previous catches in the winter months in Nebraska.

The danger of sheep overheating has traditionally led wildlife researchers to hunt when it is cold. Todd Nordeen, manager of the big game disease and research program, said the decision to try it in September was influenced by other western states that have recently had success harvesting sheep in the summer. A considerable benefit, he said, is that the sheep have not yet grown out of their heavy winter coats that hamper cooling efforts.

Much attention was paid to the body temperature of the sheep from the time they were captured until they were released. Being delivered from the helicopter, they were doused with water.

Nordeen said the efforts were successful, with all of the captured sheep surviving the process.

Another change is the technology of tracking collars. Previous collars have been limited in battery life and required retrieval for replacement, but the ones installed this month are solar powered. Unless they malfunction, they are expected to last the life of the animal without needing to be replaced, and can even be removed remotely. That, Nordeen said, means the animals may not need to be recaptured.

Site processing was done at Williams Gap Wildlife Management Area on September 20 and Cedar Canyon WMA on September 21. Each of those areas was extensively burned by wildfires this summer. While the wildfires have had some immediate effects on bighorn sheep, the long-term effects on their habitat should be minimal, he said.

“It’s been an interesting couple of years with all the wildfires we’ve had, especially in the Wildcat Hills where we have a lot of bighorn sheep,” Nordeen said. “It has had an impact on them, at least initially, driving them out of certain areas for a short time. But, they seem to turn around and eventually return to those burned areas.

“They like that area, and they stick to it.”

Nebraska bighorn sheep, which were reintroduced to Pine Ridge in the 1980s and later to Wildcat Hills, have long suffered losses from disease caused by mycoplasma bacteria, as they have in other states. The bacterium causes serious illness and mortality among herds. Collaring efforts allow tracking of animals which provides vital data that can be used to find solutions to the problem.

“It’s been a challenge for us and for the entire country,” Nordeen said. “It’s been a long road, but we’re still trying to turn things around.”

Conservation partners from the Game and Parks Commission heavily funded the effort. They include the Wild Sheep Foundation, the Iowa Foundation of North American Wild Sheep, the Nebraska Big Game Society, and Platte River Basin Environments.