Not sure how true this is but I've read that large pike will behave differently than small ones, and will go deeper in the summer, towards colder water. Not sure how applicable this would be to a river system where the water is mixing, or to St Law specifically which has relatively cooler Lk O water coming in, but point being: you may indeed need to look to different types of areas than you're currently fishing. Could be holding in deeper water using the slack water behind humps or even chasing baitfish in open water.
Check it out and let us know what you find
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