Fort Smith, Montana

Best Flies For Bighorn River

Updated Apr 24, 2026, 7:36 AM MDT

Stay with a precise nymph rig built around sowbugs, scuds, and small baetis, then be ready for pods of risers if the river gets a quiet overcast window.

Current Conditions
  • Flow: Tailwater flows can shift with dam releases, but trout usually stay in defined seams and shelves until flows move hard.
  • Water Temperature: Stable spring temperatures keep fish willing, but they still slide into softer edges when releases bump up.
  • Weather: Even modest cloud cover can turn on better olive activity here.
  • Overall Rating: 8/10
Today's Read

Bighorn River is fishing around blue-winged olives and midges. Start with the patterns below and adjust only after fish show you something different.

Best Flies Right Now
  • Ray Charles, size 16-18, nymph
  • Pink Scud, size 14-18, nymph
  • Zebra Midge, size 18-20, nymph
  • BWO Soft Hackle, size 18-20, emerger
  • CDC BWO, size 18-20, dry
What They Match
  • Blue-winged olives, size 18-20, midday under clouds
  • Midges, size 18-22, morning and slower evening slicks
  • Scuds and sowbugs, size 14-18, all day subsurface
How To Fish These Flies
  • Use a shallow indicator rig unless releases are up. Most fish eat better on short, controlled drifts than on a deep bobber setup.
  • Concentrate on slick shelves, tailouts, and the slow center seam of broad runs.
  • If fish start rising, switch to an emerger or cripple first. Trout here often prefer bugs in or just under the film.