U.S. Interior Secretary Ryan Zinke’s statement last week announcing his decision to halt discussion surrounding the return of the National Bison Range to the Confederated Salish and Kootenai Tribes has sparked some head scratching among parties on both sides of the issue.

“I’m as curious as anybody else as to why this got to the top of (Zinke’s) to do list,” said Tom France, senior director of Western Wildlife Conservation for the National Wildlife Federation, which supported the proposed transfer.

Days before President Donald Trump took office in January, the U.S. Fish and Wildlife Service under the outgoing administration had initiated an environmental review to explore the possibility of the transfer. The Bison Range is part of the National Wildlife Refuge System administered by the federal agency.

In his emailed announcement, Secretary Zinke stated that he was changing course, citing a commitment never to sell or transfer public land. The range was established as a refuge for the few remaining American Bison in 1908 by President Theodore Roosevelt, who Zinke has repeatedly mentioned as an icon when it comes to conservation policy.

Despite its adherence to talking points, France said Secretary Zinke’s statement leaves many elements of future range management up for interpretation.

“It isn’t clear exactly what statement he’s making, how it relates to the ongoing planning process,” France said.

Part of this ambiguity could stem from portions of Secretary Zinke’s statement stressing a desire to continue involving the tribes in range management and operations.

“The Confederated Salish and Kootenai Tribes will play a pivotal role in our discussions about the best path forward,” Zinke wrote.

While praising Zinke’s decision for keeping the range inside the National Wildlife Refuge System, an official with a group called Public Employees for Environmental Responsibility, which had sued the Fish and Wildlife Service over the transfer proposal, noted that it remains unclear what form continued tribal involvement could take.

Paula Dinerstein, senior counsel at PEER’s Washington D.C. office, said that past attempts to involve the tribes through annual funding agreements have run into legal obstacles.

She said an agreement in 2010 was shot down after it was determined to hand over certain activities referred to as “inherently federal functions” to the tribes.

PEER’s lawsuit centered around the requirement for the Fish and Wildlife Service to complete a 15-year Comprehensive Conservation Plan, which Dinerstein said had been put on the back burner due to transfer discussions.

Even with Secretary Zinke’s decision, she said she’s under the impression that the part of the plan will still involve exploring an annual funding agreement.

“To us that’s something of a mystery,” she said.

Dinerstein said PEER is not opposed to tribal involvement with the range and could support a funding agreement under the right circumstances, however, any arrangement must be built on solid legal ground.

France said he also understands the range is on schedule to complete a comprehensive plan, which might breathe new life into some of the very issues Zinke’s decision appears to lay to rest.

“That will be the vehicle to discuss how this will be managed,” France said. “A lot more will be heard on this.”

The Fish and Wildlife Service’s discussions with the tribes exploring the possible ownership change of the 18,000-acre wildlife refuge became public in January 2016. The tribes have long sought the return of the land to the Flathead Indian Reservation, after Congress, in 1908,s unilaterally removed it to create a preserve for American Bison — a species then teetering on the brink of extinction.

In an emailed statement after the announcement, CSKT Chairman Vernon Finley thanked Zinke for personally calling to announce his decision, and urged him to continue working with the tribes on management policy on the Bison Range.

“Restoration of the National Bison Range to federal trust ownership for the tribes will always be a logical solution to future management,” the statement read.