BILLINGS – Deep snows have delayed plans by state and federal agencies to start driving some wild bison back into Yellowstone National Park to make way for cattle that graze on surrounding lands in Montana.
Efforts to haze the animals into the park from the West Yellowstone area could begin in about two weeks, officials said. Those operations previously were scheduled to begin Tuesday.
Separately, on the north side of Yellowstone, about 120 bison out of almost 800 captured this winter were released back into the park over the last several days, park biologist Rick Wallen said. More releases of captured animals are expected in coming days.
About half the park’s 3,500 bison have been exposed to the animal disease brucellosis, which can cause pregnant animals to prematurely abort their young.
Bison regularly migrate outside the park in search of food at lower elevations during winter. However, they are prohibited from going very far into Montana to prevent them from spreading brucellosis to cattle.
Almost all bison that leave are captured, killed or driven back into the park by government workers.
Many of the captured animals have been held since January in government-run holding pens near Gardiner. They were spared a planned slaughter when Gov. Brian Schweitzer prohibited shipments of the animals, citing worries about spreading brucellosis.
On the west side of the park, officials say they need to get roughly 190 bison back into the park but expect to miss a May 15 target date.
“There’s still too much snow” to move them, said Montana Department of Livestock executive officer Christian Mackay. “We’ll be taking it a week at a time.”
Cattle will begin arriving in the West Yellowstone area for summer grazing in the first two weeks of June, Mackay said.
Officials said the success of their operations on both the west and north sides of the park would depend on how quickly snow inside Yellowstone melts. Unless that snow is gone, exposing the vegetation that bison eat, animals that are driven into the park could turn around and leave again.
State and federal agencies gave more leeway to migrating bison this year than in the past, allowing hundreds of the animals to linger in areas where they once faced capture and shipment to slaughter.
But that increased tolerance has been criticized by Park County commissioners and livestock groups who say hundreds of roaming bison caused property damage and threatened public safety.
A lawsuit seeking to restore restrictions on bison movements was filed Friday by the Park County Stockgrowers Association. A second lawsuit is expected to be filed this week by Park County officials.
Park County Commission chairman Randy Taylor said agencies had violated a 2000 federal-state agreement by allowing bison to roam freely — a move conservation groups had pushed for years.
“We want the Park Service and everyone to go with the agreement that we had, not turning them all loose,” Taylor said.