New herds of genetically pure wild bison may once again roam vast expanses of the American West – where the iconic animal has been absent since the end of the 19th century – under a tentative federal plan.
The proposal, for which Yellowstone National Park officials started seeking public comments this week, is almost sure to draw staunch opposition from ranchers concerned about disease, competition for grass, and property destruction from straying herds. Yellowstone is home to more than 4,000 bison (also known as buffalo), constituting the bulk of the country’s last pure-bred population of the animals.
Dozens from the park’s herd have been relocated to two Montana Native American reservations in recent years. Park officials, wildlife advocates and Native American groups are now eager to restore wild bison to more of their native habitat. A recent US Interior Department report on bison concluded they could potentially be reintroduced to swathes of public lands it manages in states such as Colorado, Arizona, New Mexico, Nebraska and South Dakota, without posing a risk to livestock.
The chief concern is brucellosis, an infection that causes stillbirths in cows and may have been transmitted to roughly half the bison in Yellowstone from exposure to cattle.
Park wildlife managers are eyeing a plan that would start by quarantining dozens of bison for several years to prevent them from contracting the disease. Those shown to be free of brucellosis could then be considered for relocation to establish controlled herds elsewhere, said David Hallac, the chief of Yellowstone’s science and research branch.
Millions of the animals once roamed the plains west of the Mississippi until systematic hunting drove their numbers to the fewer than 50 that found refuge in Yellowstone in the early 20th century. But livestock-industry representatives said even disease-free bison could prove problematic to the landscape, since the outsized animals would venture beyond fences or property lines and might compete with cattle for food. “We have legitimate concerns about containment and damage to private property and we need to address the impact on ranchers that graze on federal lands,” said Jay Bodner, the natural-resource director for the Montana Stockgrowers Association.