Rainbow Trout

Rainbow trout are a cold-water species requiring dissolved oxygen levels above 7 ppm and water temperatures consistently below 70°F. They thrive in fast-flowing, well-oxygenated streams and are also widely stocked in lakes across the Upper Midwest. Unlike brook and brown trout which spawn in the fall, rainbow trout are spring spawners — typically depositing eggs in gravel redds from March through May when water temperatures reach 42–52°F.

The vast majority of rainbow trout caught in the Upper Midwest are hatchery-raised. State agencies across all five states maintain active stocking programs, planting catchable-size rainbows (typically 10–14 inches) in designated trout waters throughout the spring and early summer. Recently stocked trout — those planted within the past 2–6 weeks — tend to hold near their stocking locations and are often the easiest fish to catch, making stocking schedules valuable intelligence for anglers.

Steelhead are the lake-run form of rainbow trout found in Great Lakes tributaries, particularly in Michigan and Wisconsin. These fish spend most of their lives in open lake water, growing to impressive sizes (8–15 pounds is common), before returning to rivers and streams to spawn in spring. Michigan’s Pere Marquette and Au Sable rivers are premier steelhead destinations, drawing fly anglers from across the country.

Rainbow trout feed on aquatic insects, small crustaceans, and baitfish. In streams, they are opportunistic drift feeders — holding in current seams and eddies where food is funneled to them. In stocked lakes, put-and-take rainbows will readily take PowerBait, worms, and small spinners. Wild and holdover trout become increasingly selective, making fly fishing and light-tackle presentations more effective as the season progresses.