The Statesman has a page of coverage about the wolf versus elk controversy. Apparently the data show that elk "harvesting" has not really declined much since wolves were re-introduced, but there are some questions about the data.
The chief opponents to wolves are elk hunters. They prefer to kill the elk themselves instead of letting the wolves do it. (I wonder why we don't hear complaints aboue wolves killing deer. Do wolves not kill deer? Or are deer just plentiful?)
It seems to me that the only way to mollify both the hunters and the wolf fans is to increase the wolf population to the point where hunters can begin hunting wolves. That way the wolves will still be in Idaho, and the hunters can have a chance to kill a wolf.