BOZEMAN, Mont. (AP) — A new study says wildlife managers should worry more about elk than bison as they seek to reduce the transmission of brucellosis to cattle in the area around Yellowstone National Park.

Brucellosis has been eradicated from the United States with the exception of areas in Idaho, Montana and Wyoming near the park. Elk have transmitted the disease, which can cause cattle to abort, but there has never been a documented case of bison transmitting the disease to cattle in the wild.

The report from the National Academies of Sciences, Engineering and Medicine said agencies should consider reducing the elk population through hunting, contraception and removing infected elk. It also suggests reducing the use of supplemental elk feeding grounds in Wyoming during the winter.

Current management efforts are focused on bison.