Bighorn River · hatch chart
A winter fishery as much as a summer one; the river is at its most consistent from November to March
By month
JanFebMarAprMayJunJulAugSepOctNovDec
| Month | Insect | Stage | Size | Time | Intensity |
|---|---|---|---|---|---|
| Jan | Midges (Chironomidae) | Pupa and adult | #18-24 | 12:00-15:00 | |
| Mar | Blue-Winged Olive (Baetis) | Emerger | #18-20 | 13:00-16:00 | |
| Apr | Midges (Chironomidae) | Adult cluster | #20-22 | 10:00-16:00 | |
| May | Black Caddis (Brachycentrus) | Adult | #16-18 | 11:00-16:00 | |
| Jun | Pale Morning Dun (Ephemerella) | Dun | #16-18 | 10:00-14:00 | |
| Aug | Trico (Tricorythodes) | Spinner fall | #22-24 | 08:00-10:30 | |
| Oct | Blue-Winged Olive (Baetis) | Dun and spinner | #20 | 13:00-16:00 | |
| Dec | Midges (Chironomidae) | Pupa | #20-24 | 12:30-15:30 |
Flow and visibility
Yellowtail is a flood-control and power dam, so winter releases are small and stable and summer releases follow irrigation demand. The practical rule: below 2,000 cfs the river fishes like a wadeable stream, above 4,000 cfs the gravel bars go under and the fish move to the bank. Water temperature stays between 5°C and 12°C, so the fish feed all winter.
The insect plate
