Optimal temperature to start looking for walleyes in big water?

Put my name down in with the (It doesn’t matter) crowd for walleyes.
They are more bait fish then temperature oriented. So, what may matter
more is where you look and fish for them during these temp changes. With
that said, I do believe all species of fish do have a water temperature
preference, will bite better, longer and more aggressively in them. But
only a few fish species seem locked into that temperature range comfort
zone when foraging for food.

Small scaled or salmo species of fish seem to be the ones to suffer the
most when out of their own temperature range preferences. And these same
species also get locked into specific forage prey that also prefer those
same comfort zones. Walleyes and other rough scaled species do not
suffer these same restrictions IMV, may initially be effected by extreme
fronts, but will eventually and quickly (in most cases) adjust to both
the temps and the change in forage when and if need be. Capt. Dan.