Barr's BWO Emerger
Imitates: Blue-winged olive emerger
Quick Reference
- Best Sizes
- #18-22
- Best Season
- Spring and fall
- Best Conditions
- Cloudy BWO hatches, tailwaters, flat glides, selective risers
- Water Temp
- 45-58°F
- Recommended Tippet
- 6X fluorocarbon
How to Rig It
Trail it 8-14" below a small dry or fish it alone on a long leader during a hatch.
How to Present It
Dead-drift in the film with no drag. Fish it where trout are bulging just under the surface rather than fully breaking the water.
Why It Works
BWOs are most vulnerable as they struggle to escape the nymphal shuck. This sparse olive pattern sits exactly in that half-born stage trout key on. When fish ignore duns, they're usually eating emergers like this instead.
History
John Barr's influence on modern trout flies is massive, and his BWO emerger fits the same philosophy as the Copper John: slim, efficient, deadly practical. It became a guide favorite on rivers like the South Platte and Fryingpan.
Pro Tip
If fish are making quiet porpoising rises in bad weather, skip the dun and fish the emerger first. That's classic BWO-emerger behavior, especially on tailwaters.
Frequently Asked Questions
When should I fish Barr's BWO Emerger?+
During spring and fall BWO hatches, especially in overcast weather when fish are rising just under the surface and refusing adult dries.
Emerger vs RS2 for BWOs?+
RS2 is more generic and can cover midges too; Barr's BWO Emerger is more specifically olive-mayfly oriented and shines when trout are locked on true BWOs.
Not sure if Barr's BWO Emerger is right today?
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