More than 50 bighorn sheep are carrying new equipment to help the Nebraska Game and Parks Commission track and aid their populations, some of which are struggling in areas of the state.
A crew of about 50 people, consisting of volunteers and Game and Parks staff members, equipped the sheep with monitoring devices after a helicopter capture crew caught them at five locations in the Panhandle earlier this month. The crew set up its mobile staging station at four locations along the Pine Ridge near Crawford and Chadron in northwestern Nebraska, and one site at the Wildcat Hills along the North Platte Valley near McGrew. In all, 51 sheep were captured — 31 in the Pine Ridge and 20 in the Wildcat Hills.
In the Wildcat Hills on the first day, 20 ewes were captured and equipped with radio collars. In the Pine Ridge on the next day, 30 ewes and one ram were captured and collared.
Most of the sheep received GPS tracking collars, an upgrade from the VHF models that have been used on the majority of the sheep in the past.
Todd Nordeen, Game and Parks’ big game research and disease program manager, said the GPS models will allow for remote monitoring via satellite and provide valuable data on habitat use while still providing VHF capabilities for locating nearby sheep with telemetry equipment.
Herds in the Wildcat Hills have done well, but the Pine Ridge has not been so fortunate. This marks the second year of the lamb-collaring project in the Pine Ridge, where no lambs survived in 2016 or 2017.
In order to collar the lambs, a special device is used. The 25 captured Pine Ridge ewes that an ultrasound revealed were pregnant received vaginal implant transmitters. The VITs are placed in the birthing canal to be expelled the moment a lamb is born. With close monitoring during the lambing period this spring and early summer, Game and Parks staff will race to capture and collar the newborns within 48 hours of birth. Any longer than that, they become much harder to catch in the rocky terrain. The ewes carrying VITs represent about half of the female population in the Pine Ridge.
This year, the lambs will be given antibiotics to bolster their chances of survival, with hopes of developing a class of animals for reproduction. Nordeen said the Pine Ridge herds are in jeopardy of being lost if the lambs keep dying. Although tissue samples have determined that the sheep are dying from pneumonia, there is still a mystery about the exact culprit causing the malady.
“We’re dealing with multiple strains of bacteria, and it’s been hard to tell which is most fatal,” he said.
Through continued research, Game and Parks hopes to find the answers to the species survival.
Nordeen said the capture project and other research could not happen without the support of landowners who provide access for captures and monitoring, and the many other groups and organizations that provide financial and volunteer assistance.
A hunting season that occurs in years that enough older rams are present to warrant it also funds the research. In those years, hunters who win permits by lottery and auction harvest a total of one or two older rams.