I live in North Bay and fish Lake Nipissing all the time. I have never caught one during the soft-water season. I would think that if you were going to find them during the summer they would be suspended off some sort of deep structure. If you are fishing from shore in Callander Bay, I doubt that you would catch any...but I could be wrong.
On a side note, the Callander town dock is a great place to catch walleye, pike and sheepshead right now. If you are stuck on shore, that would be a good place to try. If I can help you with anything else, let me know
Mike