WASHINGTON - The U.S. Fish and Wildlife Service is reducing the number of federal workers at Montana's National Bison Range, citing a lack of funding, and is moving some of the animals to federal reserves in other states.

The decisions complicate the relationship between the federal government and the Confederated Salish and Kootenai Tribes. The range lies within the boundaries of the Flathead Indian Reservation..

In December, the Interior Department abruptly canceled an interim plan that had allowed the tribe a role in managing the range. Later that month, the department reversed that decision, saying it would re-establish that relationship in 2007, under certain conditions.

But the new contract is still being negotiated, according to the Interior Department, leaving future control of the range up in the air.

"We don't have a contract right now," said Dean Rundle, a refuge supervisor for the Fish and Wildlife Service.

Because the range is currently under federal supervision, it is eligible for nationwide cuts in staffing within the National Wildlife Refuge System.

Rundle said the government has currently authorized 17.5 jobs on the range. The cuts, effective immediately, will bring the number of full-time employees down to 6.3.

Because many of the current jobs are vacant and some workers are planning to change jobs anyway, Rundle said, the agency will not have to lay off any workers. Temporary and seasonal workers will pick up the slack, he said.

In a statement, Mitch King, the agency's Mountain-Prairie regional director, said the range has "played an essential role in the conservation of American bison for nearly a century."

"It is important, however, to remember that the National Wildlife Refuge System is constantly changing and adapting to meet the nation's conservation challenges, including operational realities that require we focus on our core mission and trust responsibilities," King said. "The changes at the range reflect this reality."

The Fish and Wildlife Service began moving some of the bison among ranges late last year, to better manage the bison and preserve their genetic purity.

Because of the ongoing relocations, fewer staff will be needed, the release said.

Tribal spokesman Robert McDonald said the Confederated Salish and Kootenai Tribes were surprised to hear that the agency was reducing the herd.

"Tribal members started this herd," he said. "To see the herd broken up and sent in a dozen different directions is heartbreaking … Had the (agency) been cooperative in working with the tribes, this drastic reduction may have been avoided and the general public would be served better."

He added that tribal leaders "are still operating under the belief that the Interior Department is working toward its pledge of reinstating a contract to return CSKT workers to the bison range."

The joint management plan was controversial from the start.

Environmentalists have worried that tribal management could lead to reduced stewardship. And federal employees at the range have complained of mistreatment.

The Salish-Kootenai deny those charges and maintain that they should manage the land to which they have historical ties. The range lies within the Flathead Indian Reservation.

Two years ago, the tribes and the federal agency reached an interim agreement that allowed the tribes to take on some management responsibilities at the federal bison range.

The agreement expired in September 2006, but the two governments had agreed to continue honoring it while anticipating negotiations aimed at producing a permanent management plan.