Small Streams
SMALL STREAMS
ReportThe Teton River in the basin is likely our most popular small stream, but its best fishing days this season are numbered. Terrestrial insect patterns work best on warm, sunny middays. Mayflies — BWO, smaller numbers of mahoganies and hecuba — bring trout to the top water best on overcast days. Caddis, although diminishing in general, are active during late afternoons. The same applies to most of our small streams.
Although water temperatures are about ideal, reduced flows, fewer daylight hours, and cooler nights mean a change in fly fishing strategy is upcoming. Trout will soon be heading to the deepest water to seek cover, and wet fly fishing will produce more action.
Flow has been reduced on the Blackfoot River below the dam. This means easy wading, but makes hard-sided boating nearly impossible. Birch Creek remains good fly fishing during warm days because of the numerous springs entering.
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Terrestrials (Ants & Hoppers) | #10–16 | Active | Warm, sunny midday |
| Blue-Winged Olive (BWO) | #20–22 | Active | Overcast periods |
| Mahogany Dun | #14–16 | Light | Overcast periods |
| Hecuba | #10–12 | Light | Overcast periods |
| Caddis | #16–20 | Diminishing | Late afternoon |
- MIDDAY (11 AM – 2 PM): Fish terrestrial patterns — hoppers and ants — on warm, sunny stretches of the Teton and other small streams.
- OVERCAST PERIODS (ANY TIME): Switch to BWOs, mahogany duns, or hecuba patterns when clouds move in; these mayfly hatches are most reliable under gray skies.
- LATE AFTERNOON (3 PM – DUSK): Cover the water with a caddis dry as diminishing but still-present flights pick up; transition to wet flies and soft hackles as light fades.
