Most of the country's bison herds have crossbred with domestic cattle, but one purebred herd still roams in Yellowstone National Park. About half of the park's 4,600 purebred bison are thought to have been exposed to brucellosis, a bacterial infection that also affects cattle.
Nearby ranchers want the wild beasts inoculated against the disease to help protect their cattle herds. Capturing the bison and administering vaccines is out of the question. Because they're wild. Is shooting medicine into each of the animals with an air gun every year the solution?