A federal wildlife official in Billings said the government planned to retreat for now from its attempt to take gray wolves in the Northern Rockies off the endangered species list. The official, Ed Bangs of the Fish and Wildlife Service, said the government in the next week planned to withdraw a rule issued this spring. The rule was based on the assertion that the region’s approximately 1,500 wolves were recovered fully, opening the way for public hunting of wolves to begin this fall in Montana, Idaho and Wyoming. Those hunts had been in doubt since July, when Judge Donald Molloy of Federal District Court blocked them pending resolution of a lawsuit by environmentalists.