Blue Wing Olive (BWO) Flies Quick Picks
Best All-Around BWO Dry Fly: Blue Winged Olive Dry Fly - A straightforward, buggy imitation that covers the widest range of BWO species and water types. Keep this in sizes 16-20 for any tailwater or freestone stream from late winter through fall.
Best for Picky Tailwater Trout: Juju Baetis Tungsten Bead Fly - Built for pressured, gin-clear water where fish have seen every generic nymph. Its slim SuperHair body and realistic profile get eats when standard bead-heads get ignored.
Best Fast-Sinking Nymph: Tungsten Juju Baetis Fly - Ideal when you need a Baetis nymph to get down fast in a deep run or heavy riffle without adding split shot. The heavy bead and slim profile drop it into the strike zone quickly.
Best Starter Assortment: Rio BWO Dry Fly Assortment - Good for anglers who want a reliable BWO lineup without guessing sizes and styles. It covers go-to imitations for shoulder-season hatches so you are not caught without the right pattern.
Best High-Visibility Parachute: Parachute Blue Winged Olive BWO Dry Fly - Suited to anglers who struggle tracking small dries on broken or glary water. The post rides low like the naturals but stays easy to pick out at distance.
How to Choose Blue Wing Olive (BWO) Flies
Dry Fly or Nymph
Dry flies: Fish these once you spot rising fish or steady surface activity, typically during the hatch window on overcast, drizzly afternoons when BWOs pop in numbers.
Nymphs: BWO nymphs work all day, every day, since trout key on Baetis nymphs drifting near the bottom far more often than they eat the adult on top. Start subsurface if nothing is rising.
Size Selection
Sizes 18-22: Match these to the smaller late-season and tailwater BWO broods, especially on heavily fished rivers where trout inspect flies closely.
Sizes 16-18: Cover the more common early-season and freestone hatches, giving you a fly that is easier to see and tie on without sacrificing realism.
Pattern Style
Parachute style: Choose this for calmer flows and technical presentations where the low-riding profile and visible post matter most.
Standard hackled ties: Better suited to riffled or broken water where extra hackle keeps the fly floating high through faster currents.
On-the-Water Tips
Fish overcast days hardest: BWO hatches are heaviest on cloudy, drizzly, or snowy afternoons, so plan your trip around bad weather rather than avoiding it.
Downsize your tippet: BWOs hatch when water is often low and clear, so drop to 5X or 6X fluorocarbon to avoid spooking selective fish.
Cover the water column: Run a Baetis nymph as a dropper below a dry fly to fish the emerger stage and the adult at once.
Watch size, not just color: Trout keying on BWOs are usually pickier about size than exact shade, so carry a range from 16 down to 22.
Complete Your Setup
Related Gear
Trout Flies - Round out your box with additional patterns for hatches beyond BWOs.
Nymph Flies - Add more subsurface patterns for when fish are not looking up.
Dry Flies & Spinners - Fill in your surface fly selection for other hatches you will run into on the same water.
Fly Fishing Tippet - Stock up on fine-diameter tippet for the light, technical presentations BWO fishing demands.
Blue Wing Olive (BWO) Flies FAQs
Q: What size BWO flies should I use?
A: Start with sizes 18-20 for most rivers, since that covers the majority of Baetis species anglers encounter. On heavily pressured tailwaters, size down to 20-22, and on bigger freestone hatches you can size up to 16.
Q: When do BWO hatches occur?
A: Blue winged olives are one of the most reliable hatches, showing up from late winter through fall, with the heaviest activity on overcast, cool, or drizzly days. Many anglers target them during the shoulder seasons when few other bugs are hatching.
Q: Should I fish a dry fly or a nymph for BWOs?
A: Fish a nymph like the Juju Baetis or Tungsten Juju Baetis when no fish are rising, since trout eat far more nymphs than adults. Switch to a dry fly such as the Blue Winged Olive Dry Fly once you see steady surface activity during the hatch window.