The Struggle of the Bighorn

...Partee is a game biologist with the Nevada Department of Wildlife, and six months ago, he helped to shoot and kill nearly 30 bighorn sheep in those mountains. Most of the animals were too sick to run. “The sheep were walking dead,” he recalled. “It was terrible.” The animals were suffering from a deadly form of pneumonia — one that numerous studies suggest can be passed on to wild herds during contact with grazing, domesticated sheep. The bacteria that causes it has been killing bighorns since the 19th century, and while efforts to combat the disease, along with other conservation measures, have helped to stave off the wholesale disappearance of wild sheep from the American West, its persistence has hampered a full recovery. This has officials continually scrambling to stop the spread of the disease, often through large-scale culling of sick animals or enforced separations of domestic and wild herds — though usually both. No one seems happy with these solutions. For their part, environmental and animal-rights groups decry the mass die-offs of wild sheep, and they call for more aggressive efforts to keep disease-harboring livestock at a distance. But while the separation of wild herds and grazing livestock can serve as an effective management tool, it, too comes at a cost: Ranchers rely on public lands to graze their sheep, after all, and wholesale bans on grazing have forced some herders out of business altogether. That has experts like Partee, who likened the killing of bighorns to being “punched in the gut,” looking for other strategies — although so far, science has failed to produce viable alternatives...more