Henry's Fork of the Snake · hatch chart
A true twelve-month fishery; the famous hatches are mid-June to mid-July and again in September
By month
JanFebMarAprMayJunJulAugSepOctNovDec
| Month | Insect | Stage | Size | Time | Intensity |
|---|---|---|---|---|---|
| May | Blue-Winged Olive (Baetis) | Dun | #18-20 | 13:00-16:00 | |
| Jun | Green Drake (Drunella grandis) | Dun | #12 | 11:00-15:00 | |
| Jun | Pale Morning Dun (Ephemerella) | Emerger | #16 | 10:00-14:00 | |
| Jul | Pale Morning Dun (Ephemerella) | Spinner fall | #16-18 | 09:00-12:00 | |
| Jul | Caddis (Brachycentrus) | Adult | #14-16 | 17:00-21:00 | |
| Aug | Terrestrials — ants and beetles | Adult | #14-18 | 10:00-16:00 | |
| Sep | Mahogany Dun (Paraleptophlebia) | Dun and spinner | #14-16 | 10:00-14:00 | |
| Oct | Blue-Winged Olive (Baetis) | Spinner fall | #20-22 | 13:00-16:00 |
Flow and visibility
Island Park Dam is a power peaking dam: it can move from 400 to 1,200 cfs inside an afternoon. Check the gauge before you wade, because the Ranch's soft banks go under fast. Water temperature in the Ranch sits near 9°C year round, which is why the hatches are so predictable and why the fish feed in winter.
The insect plate
