The Bush administration has given Idaho and Montana greater responsibility for managing their gray wolf populations, including increased authority to kill wolves that threaten livestock, guard animals, pets and big game herds.

Some 550 wolves live in the two states, according to federal wildlife officials. The new regulation is supposed to safeguard the predators while keeping them from expanding beyond current populations.

The rule only affects the experimental population areas established in the two states when wolves were reintroduced in the region in 1995 - these areas cover the southern half of Montana and all of Idaho except the northern panhandle.

Under the rule, private landowners - and individuals using public lands for grazing and recreation - will no longer need written permission to kill wolves they deem to be threatening their livestock or domestic animals.

The change is "a small difference, but a significant one," according to Ed Bangs, wolf recovery team leader for the U.S. Fish and Wildlife Service.

"Under the old rule, a wolf had to have its teeth in the livestock for a rancher to shoot," he said. "Under the new rule, it has to be a foot away, chasing them."

People who kill wolves will still need to provide officials with proof that the predators were an active threat, Bangs said.

Gray wolves, like this one in Montana, have been hunted and killed with more zeal than any other animal in U.S. history. (Photo courtesy Montana Fish, Wildlife & Parks Department)

The rule will not allow public hunting of wolves, which is prohibited for species protected by the federal Endangered Species Act - the gray wolf is listed as "threatened" under this law.

State officials welcomed the increased authority and said it reflects the success of the effort to reintroduce wolves to the Northern Rocky Mountains.

The old rule was designed "to oversee a small, reintroduced population," said Jim Caswell, administrator of the Idaho Office of Species Conservation. "This new rule offers the flexibility needed to manage a wolf population that has surpassed 500 wolves statewide."

Critics fear the new rule allows the killing of wolves as a first, rather than last, resort and could undermine recovery of the species.

Nina Fascione of Defenders of Wildlife, a leading wolf advocacy group, says that although the organization supports "strong and active state participation in managing wolves, it is essential that such management does not erase or compromise the incredible achievements made under the reintroduction program to date."

"The new rule potentially jeopardizes wolf recovery efforts just as they were beginning to show some success," Fascione said.

The regulation advances the Bush administration's plan to delist the gray wolf from the federal endangered species list and turn over authority for safeguarding the species to state governments - a policy that has become embroiled in litigation.

There is little dispute that gray wolves have recovered in some areas, but there is a passionate debate as to how existing populations should be managed and whether the recovery goals laid out for the species by the Endangered Species Act have been met.

The gray wolf, also known as the eastern timber wolf, once roamed from coast to coast and from Canada to Mexico, but by 1973 only a few hundred remained outside of Alaska.

Conservation efforts have helped build the numbers to some 4,000 - the majority inhabit Minnesota, Michigan and Wisconsin.

Officials estimate 760 additional wolves are spread across Idaho, Montana and Wyoming.

Wild gray wolf pup in Idaho explores its environment. (Photo courtesy Wolf Education and Research Center)

The downgrade in status and subsequent delisting plan rests on the division of the species into three Distinct Population Segments (DPS) within the lower 48 states.

Using those divisions, the administration contends recovery in the three Northern Rocky Mountain states equals recovery for all nine states in the Western DPS - likewise, success in three Great Lakes states means the species has recovered across all 20 states of the Eastern DPS.

That logic has outraged conservationists, who have filed separate lawsuits in federal courts in Oregon and Vermont to block the plan.

By law, delisting of the gray wolf depends on federal approval of state management plans that ensure the species' population will be maintained above established recovery goals.

The Fish and Wildlife Service approved plans submitted by Idaho and Montana, but last January rejected Wyoming's proposal.

The federal agency objected to Wyoming's desire to designate wolves in some areas as predators - a designation that allows the animals to be killed at any time and anywhere - and also criticized the monitoring requirements and biological underpinnings of the plan.

Wyoming has filed suit in federal court to overturn the decision.

Interior Secretary Gale Norton says the dispute over Wyoming's plan should not prohibit the federal government from granting Idaho and Montana increased authority for managing the species in their states.

The rule provides "a logical transition until the wolf population can be delisted and states can assume full management responsibility," Norton told reporters Monday.

The new wolf regulation is set to take effect on February 2.

Wolf in Yellowstone National Park (Photo courtesy NPS)

"Partnering with local stakeholders on wolf recovery is absolutely essential to the future of the species and we're pleased to be able to provide this vital assistance to livestock owners in the region," said Rodger Schlickeisen, president of Defenders of Wildlife. "The program is highly effective in building tolerance for wolves while helping most ranchers and farmers with the cost of livestock losses to wolf depredation."

In the 17 years since the program began, The Bailey Wildlife Foundation Wolf Compensation Fund, named in honor of its largest contributor, has reimbursed more than 300 ranchers and livestock owners in the Northern Rockies more than $440,000 in livestock compensation payments.

Defenders supports the use of nonlethal deterrents and preventative animal husbandry practices including guard dogs, electric night pens, flags, and task-specific range riders.

On December 28, Defenders announced the development of a Livestock Advisory Council, composed initially of sheep and cattle ranchers from Montana, Idaho and Arizona, who are evaluating and offering improvements for these programs.

"The compensation program really speaks to the commitment of Defenders to assist ranchers with the impacts of wolf reintroduction," stated Jan Holder, an Arizona cattle rancher and Council member. "It's amazing and wonderful that an environmental group will go to such lengths to help people on the land."