There's a bighorn sheep killer on the loose, and it's not a natural predator. Instead, it's a bacterial disease —Mycoplasma ovipneumoniae — a respiratory disease that can cause a die-off for sheep of all ages if a herd is infected.
California bighorn sheep don't just live in the Golden State — they also live in Oregon, inhabiting some of the most rugged environments in the state. But even in high altitudes over rocky terrain, they can't outrun this respiratory disease.
The pneumonia has killed wild sheep in Oregon and other Western states over the past few decades, and is considered the largest risk to wild sheep populations, according to the Oregon Department of Fish and Wildlife.
Oregon State University researchers have taken on the study of a range of aspects of the California bighorn sheep herd in the state to gain insight into the animal's risk of contracting this killer bacterium known as M. ovi (pronounced "m-ovee"). The researchers are monitoring sheep movement, how the animals use their habitat and their survival rates. The disease can spread through contact between domestic sheep and bighorn sheep, or from bighorn to bighorn.
While California is part of the bighorn sheep's name, Oregon counts 3,700 of these animals in 32 different herds in the state. They live in central and southeast Oregon. ODFW traditionally captures and relocates California bighorn sheep around the state each year, to improve genetic diversity and restore the species to its historic range in Oregon.
But the relocation is on hold this year while wildlife managers learn more about M. ovi, in part through the OSU work.