Fly hatch chart with emergence dates and recommended fly sizes for the major mayfly, caddisfly, and stonefly hatches occuring along the Lochsa River in northern Idaho. Peak hatch dates and availability may vary due to changes in annual water flows and weather conditions.

Mayfly, caddis and stonefly emergence dates may vary 1 to 2 weeks based on seasonal flows and weather conditions. A late spring will often delay emergence dates on the Lochsa River. Fishing wet flies and nymph patterns prior to an upcoming hatch can be effective for targeting trout subsurface.