Find the food source for them. Sounds easy enough but it's going to require hundreds of holes and a lot of time but worth it in the long run. They're eating something and reacting to its actions, moving great distances in open water is no big thing for them and they'll do it to survive. May wish to consider any deep(ish) mucky areas where the phytoplankton and asst. small stuff are active during the day and draw the smaller minnows that feed on them which in turn draws the predators. It's a food chain thing and you need to explore it to figure it out, There're no hard, one approach answers all deal, every lake is unique in some way and stays that way until someone takes the time and effort to figure it out. They may even be deep in that timber