Southwestern Montana
SOUTHWESTERN MONTANA
ReportFrom the no-boating section down to Ennis Lake, terrestrial insect patterns work best during daytime hours, with caddis life cycle patterns taking over as best during evenings. Rain showers have discolored the water slightly in the Gallatin and Madison Rivers from time to time. When discoloration occurs, switch to nymphing. Otherwise, stay dry using terrestrial insect patterns — early in the day try BWO life cycle and trico patterns.
The river between Hebgen Lake and the Yellowstone Park boundary remains on a Hoot Owl restriction. Check the Fish, Wildlife, and Parks website to find all Hoot Owl locations.
Gulpers on Hebgen Lake's Madison Arm provide some fly fishing during wind-free periods. Tricos now make up the bulk of hatching mayflies, with some callibaetis also active — each of which attract gulpers. Brown and rainbow trout are migrating from Hebgen Lake into the Madison River within Yellowstone Park.
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Terrestrials (ants, hoppers) | #10–16 | Strong | Midday through afternoon |
| Caddis | #18–20 | Strong | Evening |
| Blue-Winged Olive (BWO) | #20–22 | Moderate | Early morning |
| Trico | #20–24 | Moderate — bulk of hatching mayflies | Early morning; gulpers on Hebgen Lake Madison Arm |
| Callibaetis | #16–18 | Light to moderate | Morning; wind-free periods on Hebgen Lake |
- EARLY MORNING (first light to 9 AM): BWO life cycle and trico dry patterns on the river; trico and callibaetis gulper fishing on Hebgen Lake's Madison Arm during calm, wind-free periods
- MIDDAY TO AFTERNOON (9 AM to 5 PM): Terrestrial patterns — hoppers and ants — from the no-boating section down to Ennis Lake; switch to nymphs if rain discolors the water
- EVENING (5 PM to dark): Caddis life cycle patterns take over as the top producer on both the Madison and Gallatin Rivers
