Salmonfly
Imitates: Adult Pteronarcys californica (giant Western salmonfly)
Quick Reference
- Best Sizes
- #4-8
- Best Season
- Late May through early July (the Salmonfly Hatch)
- Best Conditions
- Big Western rivers — Madison, Big Hole, Yellowstone, Deschutes, Henry's Fork during the hatch
- Water Temp
- 50-60°F (the hatch trigger)
- Recommended Tippet
- 2X-3X mono
How to Rig It
Single dry on a 9 ft 2X-3X leader. Slap it hard against the bank — salmonflies fall in clumsy.
How to Present It
Bank-bash with aggressive casts tight to overhanging willows. Twitch occasionally — real salmonflies struggle on the surface. Don't pick up too soon; let it ride through every seam.
Why It Works
Salmonflies are the largest stoneflies in the West, 2-3 inches long. When they hatch in late spring, every trout in the river goes berserk for the easy 800-calorie meal. The orange-pink belly and black back are the universal trigger.
History
Pteronarcys californica is the giant Western salmonfly that has shaped Western fly fishing for a century. The hatch follows a temperature wave up rivers like the Madison and Big Hole, drawing anglers from around the world.
Pro Tip
Time the hatch by water temperature — salmonflies emerge when bottom temps hit 50°F. Fish 25-50 miles upstream of the leading edge of the hatch; trout there are still hungry, while fish at the leading edge are stuffed.
Frequently Asked Questions
When does the salmonfly hatch happen?+
Late May through early July on Western rivers. The hatch progresses upstream as water warms — start low on the river and follow it up.
What is the salmonfly hatch?+
The annual emergence of giant Pteronarcys stoneflies (2-3 inches long) on Western trout rivers. The biggest dry-fly event of the year — every trout eats them.
What size hook for a salmonfly pattern?+
Size 4-8 dry fly hook. Salmonflies are huge — match the natural with a big foam-bodied dry that floats high.
Not sure if Salmonfly is right today?
Get a fly recommendation based on live water temp, flow, sky, and time of day for any river in the US.
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