BILLINGS, Mont. (AP) - A high-profile initiative to spare a small number of Yellowstone bison from slaughter has been delayed until at least this fall, after a Wyoming Indian reservation reversed its plan to take the animals. Because about half of Yellowstone National Park's bison test positive for the livestock disease brucellosis, most of those that roam outside the park are captured and slaughtered. In recent years the government started sparing a small number of animals without the disease. The plan is to use the bison to re-establish herds beyond Yellowstone. The first 48 bison were supposed to move to the Wind River Indian Reservation in May. However, members of the Northern Arapaho recently told officials they don't want the animals on 30,000 acres of tribe-owned ranchland that had been slated to receive the bison. They reportedly said it would put the animals too close to cattle. Federal officials hope to be able to find public or tribal land for the bison this fall. Veterinarian Jack Rhyan says in the worst case, the animals could be sent to slaughter.