Blue Wing Olive (BWO) Mayfly Patterns

Blue Wing Olive (BWO) Mayfly Patterns in-stock, no sales tax - $50 orders ship free in USA.

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Many different mayfly species are predominately olive colored. Others which are gray, yellow or brown have variants towards the olive tones. Pale Morning Dun and Pale Evening Dun mayflies can be light olive or light green. Callibaetis are usually gray or brown, but in some very rich lakes they can be light olive on the belly. Baetis mayflies are predominantly olive on the belly. BWO sizes range from #14 - #20. Natural olive tones vary from yellow-olive, to grey-olive, to brown-olive.
Blue Wing Olive Sparkle Dun Blue Wing Olive Thorax
Blue Wing Olive Cripple Blue Wing Olive Parachute
It’s Blue-winged Olive Time Again!
By: Rick Hafele  
Deschutes River Trout School Featuring Mark Bachmann & Rick Hafele

Dave Hughes took this fat rainbow on a little size 18 BWO nymph fishing the soft water
about 15 feet out from the bank.
Where would we be without blue-winged olives? These little guys pop up on trout streams throughout North America numerous times during the year, and the mid-winter to early spring hatch is one of the best. By late January hatches are starting to get good, by mid February they are typically great, and they usually continue to stay strong through March and into April. If you remember your bugology you'll know that BWOs belong to the family Baetidae and genus Baetis, and the nymphs, though small, are excellent swimmers. Plus, these little nymphs are either fearless or don't have brains in their tiny heads, because they routinely let go of the stream bottom and drift in the current where trout find them next to impossible to pass up. In many trout feeding studies, BWO nymphs often make up 50% or more of the food in their stomachs. And during a good hatch of BWOs, emerging nymphs are even more numerous in the drift and more frequently eaten by trout.

One of the key facts to remember about BWOs is that they are small. A mature nymph in February may reach a size 16 if you’re lucky, and just as often you’ll need a size 18 to match them. Another thing to remember is that during a good BWO hatch trout will at one point or another feed on nymphs swimming to the surface, nymphs hanging in the surface film while in the process of emerging into duns, and duns floating on the surface before taking flight. What this means is that you will want to be armed with a series of patterns that match the different stages of BWOs during their emergence. As you might imagine fly tiers have designed a wide array of patterns for this job. The few I show here are ones I like to fish, but they by no means represent the only effective patterns out there. Below is a brief summary of how the action might unfold during a winter day’s hatch of BWOs.

BWO nymphs are tiny swimming mayfly nymphs that frequently end up drifting in the current. Little nymph patterns that match them are effective throughout they year.

Note the lighter color on the underside of the dun. Dun patterns should match this color rather than the darker color on the dun’s backside.

This female BWO dun made it off the water but still has to molt into a spinner, mate, and then lay eggs before her life is a success. BWO duns vary in color from shades of light brown, olive, or gray.

This is a male BWO dun, which can quickly be determined by its large reddish colored eyes. Females always have small dark eyes.
10:00 am: Winter fishing doesn’t require an early start, and ten is a reasonable time to get on the water. With no duns or rising fish in sight rig up with a nymph. I like to use two nymphs and one of my favorite winter combinations is a size 12 green rock worm nymph followed by a size 16 or 18 BWO nymph. Even with two nymphs you’ll normally need some extra weight on your leader to get them near the stream bottom. Once you’re rigged fish this nymph combo wherever you find good looking trout water. The soft water below a riffle is a great place to fish in the winter when trout are a little more sluggish from the cold temperature.
12 – 2:00 pm: Duns will likely start showing up in good numbers sometime in this time frame. If it's a sunny day the hatch will likely be fairly light and short. If it's an overcast day with little or no wind get ready for a good hatch. If the day looks and feels like snow and a few light flurries drop from the sky, get set for a great hatch. Duns emerge from both fast choppy water and the slack water below riffles, but some of the best trout will be feeding in slow water along the edges of faster currents, and never pass by an eddy without taking a close look for a big trout feeding quietly below the foam line. During this period of the hatch you will need both emerger patterns and dries. While starting with a dun pattern is fine, if you aren't getting any action with it don’t waste too much time and switch to an emerger pattern. Fish the emerger in the film, drag-free, just like a dry fly. This is fun fishing. Takes will be a gentle sip or slurp followed by a head shake. Just gently pull your rod tip to the side to set the hook and be ready for a strong run by a large trout. You'll probably be using 5x or 6x tippet, so you can't be too aggressive when playing a good trout, but don't baby them either, keep the pressure on and land them as quickly as possible.
2:00 – 4:00 pm: Depending the day and conditions you might see a decent spinner fall just when the duns stop emerging. These little spinners are next to impossible to see on the water, so pay attention to their mating swarms in the air. If you see some mating swarms followed ten or fifteen minutes later by subtle rises with no apparent bugs on the water, switch to a spinner pattern. In the winter spinner falls may also occur in the late morning before duns start emerging, so always stay on the lookout for them.
Any day on a trout stream is a good one, but there's something special about a winter hatch of BWOs that get good trout up off the bottom of the stream and feeding like it's summer again.
Be prepared with an adequate fly selection to be able to capitalize on all stages of the hatch. These two links will take you to every thing you need:

Blue Wing Olive Sparkle Dun

A very effective dry fly/emerger, simulates an emerging dun with a trailing nymphal shuck.
Item Description Size Price To Top
15798 Blue Wing Olive Sparkle Dun 18 3 for $5.85

Blue Wing Olive Cripple

The best way to fish this fly is to treat the front half of the body with floatant and wet the rear half. This fly often works best as the hatch is winding down.
Item Description Size Price To Top
10-00220-16 Blue Wing Olive Cripple 16 3 for $5.85
10-00220-18 Blue Wing Olive Cripple 18 3 for $5.85

Blue Wing Olive Thorax

The Thorax Dun series are great searching flies when fishing water that has a textured surface. They can simulate several species of mayflies.

Item Description Size Price To Top
26-0060-16 Blue Wing Olive Thorax 16 3 for $5.85
26-0060-18 Blue Wing Olive Thorax 18 3 for $5.85
26-0060-20 Blue Wing Olive Thorax 20 3 for $5.85

Parachute Blue Wing Olive 
This is a have to have pattern when fishing western streams and lakes. The wing is blue dun colored poly, which give the fly superior floatation. The wing post may be trimmed or colored with a felt marker to suit the fishing conditions.
Item Description Size Price To Top
12066 Blue Wing Olive Parachute 14 3 for $5.85
12067 Blue Wing Olive Parachute 16 3 for $5.85
12068 Blue Wing Olive Parachute 18 3 for $5.85

The key to success is "understanding".  You can never know enough.
Understanding the organisms that trout feed on is one of the keys to catching trout.
The Hatch Guide For Western Streams by Jim Schollmeyer 
is great reference material for the trout fisher.
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