Nevada wildlife officials say the biggest threat to the state’s desert bighorn sheep is bacterial pneumonia, which continues to kill off entire herds statewide.
The Las Vegas Sun reported that the problem was first identified in 2012 and has afflicted herds of the bighorn sheep across the U.S.
Desert bighorn sheep, Nevada’s official state animal, number about 10,400.
Pat Cummings, a game biologist for the Nevada Department of Wildlife said officials have learned more about the origins and spread of the disease, but “it’s not in any kind of control.”
Nevada Department of Wildlife veterinarian Peregrine Wolff said the sheep likely first caught the bacteria generations ago when they were brought to the U.S. from Europe. Wild bighorn sheep had no immunity to the bacteria, unlike domestic sheep, which has left them vulnerable.
Nevada wildlife officials are surveying the estimated 100 herds of bighorns in the state over the next few months. They’re collecting tissues from sheep in each herd to try to identify if they have any conditions that could make them more vulnerable once exposed to bacterial pneumonia, and try to determine what percentage of Nevada’s herds are infected.
Wolff said biologists also want to learn why some herds recover from the disease and others are wiped out.
Nevada’s Wildlife Department hasn’t determined if the disease is less widespread than five or 10 years ago, but officials are encouraged that more lambs have been seen than expected in herds where the disease was present.
That could indicate that the bighorn population is starting to see more recovery from the disease, but, Cummings said, it’s too early to tell.