CHEYENNE - It has been almost two years since the U.S. Fish and Wildlife Service began reviewing a proposal to remove the Preble's meadow jumping mouse from the list of threatened and endangered species.

But the agency still has not issued a final decision, and now the state of Wyoming wants a federal judge to compel the agency make up its mind.

A lawsuit filed last week asks U.S. District Court to force a final action within one month. It also asks the court to direct the Fish and Wildlife Service to strip the 3-inch mouse of its federal protection.

"We've asked the court to put them on a deadline," state Attorney General Pat Crank said.

The Fish and Wildlife Service acknowledged Monday that the agency response is late. After missing a 12-month deadline in February 2006, it announced a six-month extension, which it also failed to honor.

Chuck Davis, endangered species litigation representative for the Fish and Wildlife Service, on Monday blamed the delay on complicated science involved in the decision, and the far-reaching impact it could have on the application of the Endangered Species Act.

At question is whether the Preble's meadow jumping mouse is a distinct subspecies. The decision, based on genetic research, could set a precedent for how subspecies are identified in the future, Davis said.

"We're still working on this, and we anticipate a decision in June of this year," he said.

The state also wants the Fish and Wildlife Service to consider whether the mouse is more abundant than believed when it was initially listed as threatened in 1998. If so, delisting could occur even if the Preble's is a distinct species. So far the agency has not addressed that contention, Crank said.

The mouse, which uses its 6-inch tail and strong hind legs to jump a foot and a half in the air, inhabits grasslands that include prime real estate along in northeast Colorado and southeast Wyoming.

The state of Wyoming and a coalition of Colorado landowners, farmers and businesses petitioned the federal government in 2003 to take the mouse off the threatened species list.

In 2005, the Interior Department proposed eliminating the mouse's protection based on a study by Denver biologist Rob Ramey that found the mouse was indistinguishable from other, more common jumping mice.

A panel of outside scientists convened by Fish and Wildlife later concluded that the mouse is a unique subspecies.

Supporters of stripping the mouse's protection contend environmentalists are using the mouse to stop development. Nearly 31,000 acres in Colorado and Wyoming have been designated as critical habitat to help the mouse recover, and critics say resulting land-use restrictions have blocked or added to the cost of construction and water projects.

Paul Kruse, a Cheyenne consultant who has worked for several government agencies on Preble's issues, says Wyoming developers pay a high price for the animal's protection.

Kruse said landowners inside the Preble's "critical habitat designation area" - including Converse, Platte, Laramie and Albany counties - bear the brunt of the impact.

One study concluded that the cost to hire consultants, modify building projects and alter farming practices would be $79 million to $183 million over the next 10 years if the mouse remains listed. A University of Wyoming study concluded that inability to use irrigated land could cause financial losses of 12 percent a year for some farmers.

"I'm as frustrated as anybody that we haven't seen the next round of documents out of the U.S. Fish and Wildlife," Kruse said after learning of the lawsuit.

Erin Robertson, a staff biologist with the Denver-based Center for Native Ecosystems, said her advocacy group also is frustrated with the lack of response from the Fish and Wildlife Service, which she called confusing.

But politics, not science, is at the heart of the argument over whether the delisting should proceed, Robertson said.

"The science really is settled," Robertson said. "Scientists agree that the mouse is unique. Now what's happening is just politicians are involved in trying to have the decision go the way they want, regardless of what the science says."

Some also say the Preble's meadow jumping mouse debate illustrates what's wrong with the Endangered Species Act.

Partly because of the Preble's case, state lawmakers last week announced legislation that would appropriate $250,000 to the state attorney general's office to sue the federal government over any failure to follow the federal Endangered Species Act or the National Environmental Policy Act.

"Basically the problem is that the federal court system has tilted NEPA in a manner in which it was never intended," Rep. Pat Childers, R-Cody, chairman of the Travel, Recreation, Wildlife and Cultural Resources Committee, told the Associated Press.

Crank said Monday he does not support the legislation.

"I have the authority presently to pursue ESA and NEPA claims and have already been supplied by the Legislature to do so," Crank said.

The state's lawsuit asks the court to declare that the Fish and Wildlife Service broke federal law by not responding to the proposal to delist. It also seeks compensation for attorneys fees.

Reach capital bureau reporter Jared Miller at (307) 632-1244 or at jared.miller@casperstartribune.net.