Ranchers and wildlife advocates squared off Thursday in a hearing over plans for Yellowstone National Park's buffalo herds.

Fewer than a score of Utahns attended the first session of the hearing, held in the Wyndham Hotel, 215 W. South Temple, and sponsored by the National Park Service. It was one of seven hearings around the country on a draft environmental impact in which the National Park Service says its preferred option is to keep Yellowstone's buffalo population at 1,700 to 2,500.Much of the plan focuses on controlling brucellosis, which the statement says originated in cattle and is now an epidemic among the buffalo.

Brucellosis causes abortions and other disorders in its victims. It was eliminated in most ranches in the country. Cattle ranchers worry that free-roaming park buffalo may spread the disease among their livestock.

If cattle were infected, Montana ranchers would no longer be allowed to ship their livestock without inspections, as they can now under the state's designation as a "class free" zone. However, the draft says that it's possible that few of the buffalo may be capable of transmitting the disease.

Kim Christy, vice president of the Utah Farm Bureau Federation, said the group is anxious for Montana cattle to keep their clean bill of health by maintaining the "class free" designation.

The bureau supports "Alternative Five, the aggressive eradication of brucellosis from Yellowstone National Park bison. Alternative Six may be acceptable if the Montana Department of Livestock were given the authority to manage special management areas," Christy said.

In Alternative Five, buffalo would be tested and those free of brucellosis would be released back into the park. Those that were positive would be shipped to slaughter. Buffalo would not be allowed outside the park.

Beasts that strayed outside the boundaries would be chased back. Any that didn't return to the park would be shot.

Alternative Six is like Five, but it also creates special management areas outside the park where the buffalo could roam.

The Utah state veterinarian, Michael R. Marshall, said he was speaking on behalf of the state when he supported the position outlined by Christy. "The United States is almost brucellosis-free in the livestock population."

Sheral Schowe, a member of the National Wildlife Federation from Salt Lake City, charged that private ranchers are subsidized at the expense of wildlife belonging to the people of America.

Park Service officials said experiments show that when animals are confined together, buffalo can infect cattle with brucellosis. However, Schowe said nobody has ever documented an instance in which wild buffalo have infected cattle.

Laura Adducci of the National Wildlife Foundation said nearly 1,100 Yellowstone buffalo were slaughtered last year.