Bill, Only a very non-scientific survey. I should have someone come in and do that professionally. These are unique lakes that were coal pits originally, but filled and established as lakes 70 years ago. Nearly 15 feet of clarity with a secchy disk. I caught a 7 pound LMB and some 3-5 pound fish last spring, but then not another bass over a pound or many small ones at all from June to October. The LMB I have seen are healthy, but these very deep, clear lakes provide lots of places for big fish to disappear most of the year.
Don, I'm sure no expert, but it sounds like your larger LMB head deep down to the thermocline in summer. Night fishing might be an option, especially with your clear water. Also, perhaps you could create some structure that runs from, say, 15 feet up to 5 feet. Just a thought.