In the May 20 Journal forum, C.R. Stucki suggested that gray wolves were historically absent from Idaho. The lack of wolf sightings in the journal of the Voyage of Discovery and later from the American Fur Company led him to his conclusion.
I read accounts of the Lewis and Clark travels through Idaho. It was likely the hardest part of their journey. According to their reports, hunters found the various species of deer, elk and other big game animals to the almost non-existent, often returning to camp with only a few forest grouse for their efforts. The pack horses had to have free range to find enough forage to stay alive. In the end, members of the Corps resorted to butchering some of their horses to stay alive. At this point, I would question why any wolf would choose to live along the route the Voyage of Discovery took through Idaho.

Fast forward three decades and read Osborne Russell’s journals. Russell was a hunter and trapper out of Fort Hall from 1837 to 1943. Russell has referenced wolves in his journal. The one reference I found interesting took place in late September 1835. Russell is by himself, an hour before daylight and he hears wolves howling about 30 paces from him and his horse. He uses his pistol and they disperse. The landmarks he gives for this area are lava flows and a high butte 25 miles from the Snake River.  

Sounds like wolves lived in Idaho to me.