Here's my take on this . Walleyes and pike have coexisted in the same bodies of water for yrs. At one time there was a misconception that the pike eat all the pickerel. Pike will hit a wally when a chance comes but to feed on walleye alone no.
Pike prefer soft finned tube shaped soft finned fish like suckers, whitefish , etc. When they get 10 plus lbs. they'll take in a 2 lb sucker and may not eat again for days. Big pike will hit there prey from the side stun it then down it, on more then one occasion I've seen a pike with a wally stuck sideways in his mouth.
As for the wolves and coyotes , if the deer pop. is high the wolf pop. will grow especially if it's a rough winter this gives the wolves an advantage good winters helps the deer pop. If deer pop. drops the wolf pop. will too . It' the cycle of life in the animal world. For people shooting them and thinking there doing some good they could never be so wrong.