On a couple lakes where areas,usually sandy or very short weed growth seemed to be carpeted with little perch there were still other age classes. Though few, from predation or poor recruitment of a spawn cycle. One lake had quite a die off late winter early spring of the perch. The older age classes acted a little like walleye. One lake had them at late ice in mild current at its outlet. On the other lake they would come up from deeper water just before dark to be in a foot to two foot weeds and would take minnows offered till dark.
One guy would sight fish in shallow water through many holes and could scratch up a half dozen or so. but on the "flats"it would take about 50 fish to get a keeper. Not saying bigger ones are where you are fishing. Health and belly contents of a couple plump ones may have clues.