The decision restores most wolves in the lower 48 states to their endangered status under the federal law and is a blow to the administration's effort to ultimately delist the species.

The ruling by U.S. District Judge Robert Jones in Portland, Oregon, specifically blocks the April 2003 rule that downgraded the status of the gray wolf "endangered" to "threatened" throughout all of the lower 48 states, bar the southwest where the species remained endangered.

The move was a necessary precursor for the administration's broad effort to delist the species and turn management and recovery efforts over to state governments.

Two wolves in South Dakota. Gray wolves once ranged across the entire North American continent. (Photo courtesy U.S. Fish and Wildlife Service)

Using those divisions, the administration argued recovery in the Idaho, Montana and Wyoming 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.

Critics contend that the success of these recovery efforts in no way warrants such a broad change in protection for the species across such wide expanses of the country.

Jones agreed and said the science and rationale used by the agency did not support a lowering protection for the species.

"This is a great victory for wolf populations within the United States, as well as for all other endangered species that are currently listed under the ESA and struggling to make a recovery," said Patricia Lane, senior attorney for the Humane Society of the United States, one of 19 conservation groups that filed the suit.

"Judge Jones made it clear that this administration will not be able to arbitrarily strip the wolf of its protection under the ESA," she said.

Federal officials are still examining the scope of the ruling and say they have yet to decide whether to appeal.

But the decision appears to have derailed recent moves by the administration to delist the species in the Eastern DPS and to give states a larger role in managing wolf populations.

Under the Endangered Species Act, 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.

In July Interior Secretary Gale Norton accepted management plans from Michigan, Minnesota, and Wisconsin and proposed delisting the species in the entire Eastern DPS.

That proposal is now in jeopardy as is the piecemeal effort to delist the species in the West.

The gray wolf, Canis lupus, was first listed as endangered on March 11, 1967 (Photo courtesy U.S. Fish and Wildlife Service)

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

But that rule, set to enter effect today, would violate the judge's ruling as it rests on the downgrade in status voided by the decision.

Passions run high with regard to recovery efforts for the gray wolf, also known as the eastern timber wolf.

The predator 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.

The vast expanse of the species' historic range is at the center of the debate - Bush administration officials say it is not consistent with the Endangered Species Act nor is it realistic to expect gray wolves to return to all of their historic range.

Environmentalists agree but argue that there are large areas of suitable habitat where wolves can and should be reintroduced before victory is declared - including Maine, Vermont and Oregon.

Rodger Schlickeisen is president of Defenders of Wildlife, which provides financial compensation to ranchers whose livestock is brought down by wolves. He says conservation groups are eager to see the wolf recover to the point where it no longer needs federal protection.

"But that recovery must be based on a proper review of the best science available," he said. "The Bush administration failed to do this and proposed prematurely removing protections for the wolf. Today the court called them on it."