The revision of a 1993 policy would allow the Forest Service ''last resort'' animal sharp-shooting from helicopters, all-terrain vehicles and poison baiting in protected wilderness areas, Katie Armstrong, a Forest Service spokeswoman, said Monday.

The policy change is not a ''back door way to open up wilderness areas to motorized vehicles,'' she said.

The changes might have implications for an ongoing Forest Service review of Idaho's proposal to land helicopters in the 2.4 million-acre Frank Church-River of No Return Wilderness.

But in January, Intermountain Regional Forester Jack Troyer, based in Ogden, rebuffed the agency's request to fast-track a waiver of the helicopter landing ban.

State wildlife officials said it would make it harder to estimate how many wolves occupy the wilderness.

Environmentalists hailed the decision, but their joy quickly turned to jitters. Jon Marvel, executive director of the pro-wolf Western Watersheds Project, said the tracking plan now could sail through the federal approval process.

Nationwide, he said foes of the federal policy revision are threatening to sue if the predator control changes become final. The Forest Service is accepting public comment until Aug. 7.