LANDER - Gray wolves will be removed from federal Endangered Species Act protection next week, barring a last-minute court injunction.

But on the eve of the official announcement by the U.S. Fish and Wildlife Service, a conservation group filed a petition claiming the agency's decision to delist the predators ignores the best available science.

And once the agency announces its delisting decision today, a coalition of up to 10 conservation groups says it will challenge that decision in court.

The Fish and Wildlife Service is scheduled to announce its plans to delist wolves this morning, and the rule will be published in the Federal Register Feb. 27.

The states of Wyoming, Idaho and Montana will assume management of wolves 30 days after the publication of the rule, barring a federal court injunction against the decision.

The Natural Resources Defense Council filed a petition Wednesday calling for the Fish and Wildlife Service to prepare a comprehensive recovery plan for wolves throughout the United States, based on the best available science, which the group says the federal agency has ignored.

"We're trying to get the U.S. Fish and Wildlife Service to get to real recovery, which is about defining recovery goals based on what the science tells us, not on 30-year-old piecemeal plans," said Louisa Willcox, a wildlife advocate with the NRDC.

Sylvia Fallon, a geneticist with the NRDC, said the Fish and Wildlife Service never developed a recovery plan for wolves as a species, and instead chose to treat separate populations in the Southwest, Midwest and Rockies differently.

"We are petitioning Fish and Wildlife to develop a plan for the species as a whole," Fallon said. "The recovery plans, developed in the '80s, are out of date, and not based on the best available science."

The current recovery goal as defined by the Fish and Wildlife Service - which, Fallon said, would allow for the total Northern Rockies wolf population to drop to about 300 wolves - is an insufficient number to maintain long-term genetic viability, Fallon said.

"The science that was available at the time, and has developed since, tells us that a population actually requires somewhere in the range of 2,000 to 5,000 wolves to keep them genetically viable," Fallon said. "Over time there will be genetic decay and inbreeding if there aren't more wolves, with more connectivity between the Idaho, Montana and greater Yellowstone populations."

Melanie Stein, a representative of the Sierra Club in Jackson, echoed Fallon's concerns.

The Sierra Club is opposed to wolf delisting, Stein said, because the animals are essentially isolated - there is no genetic mixing among the Yellowstone, central Idaho and Montana groups.

But not all conservation groups are on the same page regarding delisting. The Greater Yellowstone Coalition plans to announce its support for the delisting decision today.

"We want to move to the point where residents in Wyoming, Idaho and Montana feel ownership over wolves, and the responsibility for balanced management," said Craig Kenworthy, a conservation director with the Greater Yellowstone Coalition. "And the best way to do that, and the best thing for wolves in the long run, is to have careful and balanced state management."

The coalition is committed to working with states and residents to ensure that balance, Kenworthy said.

"We think it's time to move from protection to management, and to continue the success of the recovery. We want them treated like we treat other wildlife. We want them managed," he said.

While the NRDC and the Sierra Club claim the federal government has overlooked the best science, Ed Bangs, the federal gray wolf recovery coordinator, said there is currently no evidence of genetic decay among the wolves, and if any arises in the future, the states are committed to solving that problem.

"We've got more wolves in more places than we ever thought we'd have," Bangs said. "Fourteen years ago there were none, and now there are 1,500 wolves in Montana, Idaho and Wyoming, throughout most of the suitable habitat."

The wolf population has been increasing by about 24 percent per year since 1995, Bangs said, and as a result, stockgrowers and landowners in the three states are starting to have more conflicts with wolves.

"The big issue is, until we delist, it isn't a success story. The purpose of the Endangered Species Act is essentially to put me out of work," Bangs said. "In the long term there are some concerns about genetic diversity. I don't share them personally; right now there isn't a problem. But if it ever becomes a problem, the states are required to take care of it. It's included in their agreements."

Environment reporter Chris Merrill can be reached at chris.merrill@trib.com or at (307) 267-6722.