Henry's Fork
HENRY'S FORK
ReportOvercast conditions and right after storms offer the best dry fly fishing. The river is low, cold, and clear throughout. Nymphing remains the best producer in Box Canyon. Try terrestrial patterns during warm mid-days. Long, drift-free floats on fine leaders are needed with precise casting toward banks.
Tiny BWOs (pseudos) emerge best during sunlight conditions. Caddis are active during evenings throughout the river but are decreasing in amounts.
Brown trout are migrating upstream and are the big attraction to fishing in the river above and below Ashton Dam and around St. Anthony. Streamer patterns during low light conditions are the best producers. Flow at Box Canyon is about 180 cfs, below Ashton Dam is about 700 cfs, and about 750 cfs at St. Anthony.
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Blue-Winged Olive / Pseudos | #22–24 | Moderate — best during sunny windows | Midday to early afternoon |
| Caddis | #18–20 | Light and decreasing | Evening |
| Terrestrials (Ants & Hoppers) | #12–16 | Moderate during warm mid-days | Late morning to early afternoon |
- DAWN & DUSK: Fish streamer patterns for migrating brown trout above and below Ashton Dam and around St. Anthony
- LATE MORNING TO EARLY AFTERNOON: Target banks with terrestrial patterns (ants, hoppers) during warm mid-day temperatures
- EVENING: Swing or dead-drift caddis patterns throughout the river as activity decreases through the month
