Most anglers believe that the bigger fish move to the shoreline in the fall, but the mud flats of Mille Lacs hold fish all year around and these big fish stay and feed during the fall months. On the flats, the weather has less of an impact than it does in shallow water. Fish favor stability. Relatively constant water temperature, water quality, weather, and abundance of prey let fish live predictably. Good fishing often accompanies stable conditions, but sometimes when weather is poor fishing is the best on the flats.
Flats are the major food-producing regions of most lakes.
Walleyes forage over flats. Therefore, the flats are the home of walleyes. It's easy to identify productive flats. Some prime flats drop off steeply into the deepest areas of the lake. Walleyes that use flats typically move shallower at night to feed on a variety of prey species.