More than 50 Yellowstone National Park bison have escaped through a cut fence at a containment area where the animals were being prepared for transfer to the Fort Peck Tribes in northeastern Montana.
National Park Service officials confirmed the release Tuesday afternoon, but were still gathering details about the breach of two pens at the Stevens Creek facility.
The animals had been in containment for nearly two years to assure that before being transferred to the tribes the bison were free of brucellosis, a disease that can cause livestock to miscarry.
“The National Park Service has initiated a criminal investigation at Yellowstone National Park to investigate a trespass and tampering incident at the Stephens Creek facility,” Morgan Warthin, Yellowstone’s public affairs specialist, said in an emailed statement Tuesday. “Bison being held at the facility for possible quarantine are no longer in the pens.”
Interior Secretary Ryan Zinke called the release devastating, possibly delaying the delivery of bison to the Fort Peck Tribes for another two years. The Animal Plant Health and Inspection Service must decide whether the quarantine period will have be restarted, or whether the bison bulls that wandered away can still be considered a minimal risk for brucellosis.
“At the least we suspect it’s going to delay it, whether it restarts the clock to zero or not we have to wait and see,” Zinke said. “We were within days of actually moving the buffalo to another facility to begin the process of repatriation.”
The Fort Peck Tribal chairman was notified Tuesday night. Yellowstone National Park Superintendent Dan Wenk told Zinke that it appeared someone cut through the containment area with bolt cutters. The 54 bulls began traveling toward Gardiner, Montana. Not all of the bison had been accounted for Tuesday night.
The Stevens Creek facility was only recently converted for quarantine use. The site was previously a bison trap, but last April National Park Service officials and APHIS, a branch of the U.S. Department of Agriculture, began working with Montana livestock officials to create a new quarantine area.
There, bison were to be tested for brucellosis, with disease-free animals held for up to two years in order to be certified disease free.
Brucellosis is thought to infect half the bison in Yellowstone National Park.
Cost savings was the primary objective for the site conversion. The bison had previously been transported further north to Corwin Springs for containment, which cost more. Immediately after the site conversion, 24 bulls committed to the Fort Peck Tribes were located there. Male bison must be quarantined without incident for at least a year before being certified.
Tuesday’s breach took place as four different tribes participated in a scheduled bison harvest of unquarantined bison outside of Yellowstone, Zinke said. There was a concern that some of the released animals could be shot accidentally by members of the Confederated Salish Kootenai, Nez Perce, Yakima and Umatilla tribes.
The transfer of the bison to American Indian tribes is part of a 17-year plan to cull the Yellowstone bison population to about 3,000. Hunting is also part of that plan.