Windblown Pearl Olive Mayfly Dun
by @dekasso
Dry fly
A rumpled dun drying its wings
A size 16 olive mayfly dun with split Coq de Leon tails and a loose pearl Z-Lon wing, for trout during blue-winged olive hatches.
A small olive mayfly dun with split speckled tails and a frayed, glinting pearl wing. The body is a segmented olive biot, and the wing is loose white Z-Lon that catches light on every side.
- Imitates
- Blue-winged olive hatch
- When
- typically spring and fall afternoons, often on grey, drizzly days
- Hook
- size 16
- Tippet
- 5Xrule of three
- Split Coq de Leon tails for balance
- Segmented olive goose biot body
- Loose pearl Z-Lon wing catches light
- Size 16 for blue-winged olive hatches
- Rides low on slow, flat water
On the water

Two ginger tails flare off the bend like whiskers. A banded olive body runs forward to a tuft of pearl white Z-Lon, frayed and unruly, glinting in every direction against the slate.
Fish it on soft flats and slow runs when olives are popping on a grey afternoon. Cast above a rising fish and let it ride drag-free. The messy wing sits low and sparkles like a dun still shaking off its shuck.
Goose biot gives that clean segmented body. Wet it before tying in, and tie it by the tip with the notch facing up so each wrap leaves a fine raised ridge.

Rigging
- Tippet
- 5Xhook size divided by three
- Leader
- Nine feet, tapered — longer and finer in flat water
- Fish on 5X or 6X tippet with a long, supple leader for clean drifts.
- Dress the wing lightly with floatant and keep it off the body so it stays fluffy.
- Dead drift it into the feeding lane; a tiny twitch can wake a fish holding below.
Where and when
- Hatch
- Blue-winged olive hatchtypically spring and fall afternoons, often on grey, drizzly days
- Target
- Trout
- Water type
- Slow runs, flats and spring creeks
- Also fishes
- Also works as a cripple in film-feeding eddies, and in a pinch during small olive hatches on stillwater margins.
Make it yourself
Intermediate5 materials · 11 steps
- Style
- Dry fly
- Hook
- Standard dry-fly hooksize 16
- Thread
- Olive 8/0

Materials in the order they go on the hook
- TailCoq de Leon fibers, split
- BodyOlive goose biot
- WingWhite pearl Z-Lon
- ThoraxOlive superfine dubbing
- HeadOlive thread
Details
- Imitates
- Blue-winged olive mayfly dun
- Colors
- Olive, Pearl white, Ginger

How to tie it
The steps, from first wrap to whip finish (11)
- Mount the hook and start the olive thread one-third back from the eye, then wrap a thin base to the bend.
- Build a tiny thread bump at the bend to help split the tails.
- Tie in three or four Coq de Leon fibers each side of the bump, splayed apart, about one shank length long.
- Tie in a wetted olive goose biot by its tip at the bend, notch up.
- Wrap the biot forward in touching turns to the two-thirds point, tie off and trim.
- Tie in a small bunch of pearl Z-Lon crosswise with figure-eight wraps just ahead of the body.
- Lift and post the wing with a few wraps so the fibers stand up and flare out.
- Dub a slim olive thorax around the base of the wing, covering the tie-in wraps.
- Form a small, neat olive thread head behind the eye.
- Whip finish and trim the thread.
- Trim the wing roughly to length, then tease the fibers with a dubbing brush so they splay loose and uneven.
Proportions (4)
- Tails: about one hook shank long, split into a clear V.
- Body: rear two-thirds of the shank, slim and evenly tapered.
- Wing: roughly one and a quarter shank lengths tall, loose and uneven at the tips.
- Thorax: front third of the shank, slightly fatter than the body.
Tips (3)
- Soak the biot in water for a minute so it wraps without splitting.
- Use a dubbing brush on the wing last to open the Z-Lon fibers.
- Keep the thorax dubbing sparse; a fat thorax pushes the wing out of shape.
Common mistakes (4)
- Tails bunched together: build the thread bump first so the fibers split around it.
- Biot cracking mid-wrap: wet it well and tie it in by the tip, not the base.
- Wing too dense: start with a thin pinch of Z-Lon, since it fluffs up once brushed.
- Crowding the eye: leave room for the head and whip finish before dubbing the thorax.

Every kit size
Materials only
Size 16 · Materials only · 12 flies
$32.40
$2.70 a fly
Includes Standard dry-fly hook · and 7 more
Every item in this kit · 8 items
Hooks & beads
- Standard dry-fly hook$6.50
Thread & wire
- Olive 8/0 thread$2.95
Materials
- Other material: Coq de Leon fibers, split$4.50
- Other material: Olive goose biot$4.50
- White pearl Z-Lon$3.50
- Olive superfine dubbing$4.50
Finishing
- Head cement$5.95
Guide
- Printed recipe and tying stepsIncluded
Size 16 · Materials only · 48 flies
$52.58
$1.10 a fly
Bought separately $55.35 · you save $2.77
Includes Standard dry-fly hook · and 7 more
Every item in this kit · 8 items
Hooks & beads
- Standard dry-fly hook$13
Thread & wire
- Olive 8/0 thread$5.90
Materials
- Other material: Coq de Leon fibers, split$9
- Other material: Olive goose biot$9
- White pearl Z-Lon$3.50
- Olive superfine dubbing$9
Finishing
- Head cement$5.95
Guide
- Printed recipe and tying stepsIncluded
Size 16 · Materials only · 144 flies
$116.29
$0.81 a fly
Bought separately $132.15 · you save $15.86
Includes Standard dry-fly hook · and 7 more
Every item in this kit · 8 items
Hooks & beads
- Standard dry-fly hook$35
Thread & wire
- Olive 8/0 thread$17.70
Materials
- Other material: Coq de Leon fibers, split$22.50
- Other material: Olive goose biot$22.50
- White pearl Z-Lon$10.50
- Olive superfine dubbing$18
Finishing
- Head cement$5.95
Guide
- Printed recipe and tying stepsIncluded
With vise & tools
Size 16 · With vise & tools · 12 flies
$182.40
$15.20 a fly
Includes Standard dry-fly hook · and 16 more
Every item in this kit · 17 items
Hooks & beads
- Standard dry-fly hook$6.50
Thread & wire
- Olive 8/0 thread$2.95
Materials
- Other material: Coq de Leon fibers, split$4.50
- Other material: Olive goose biot$4.50
- White pearl Z-Lon$3.50
- Olive superfine dubbing$4.50
Finishing
- Head cement$5.95
Tools
- Rotary pedestal vise$79
- Ceramic bobbin$14
- Fine-point scissors$16
- Whip finisher$9
- Hackle pliers$7
- Bodkin$5
- Bobbin threader$4
- Dubbing wax$4
- Canvas tool roll$12
Guide
- Printed recipe and tying stepsIncluded
Size 16 · With vise & tools · 48 flies
$195.08
$4.06 a fly
Bought separately $205.35 · you save $10.27
Includes Standard dry-fly hook · and 16 more
Every item in this kit · 17 items
Hooks & beads
- Standard dry-fly hook$13
Thread & wire
- Olive 8/0 thread$5.90
Materials
- Other material: Coq de Leon fibers, split$9
- Other material: Olive goose biot$9
- White pearl Z-Lon$3.50
- Olive superfine dubbing$9
Finishing
- Head cement$5.95
Tools
- Rotary pedestal vise$79
- Ceramic bobbin$14
- Fine-point scissors$16
- Whip finisher$9
- Hackle pliers$7
- Bodkin$5
- Bobbin threader$4
- Dubbing wax$4
- Canvas tool roll$12
Guide
- Printed recipe and tying stepsIncluded
Size 16 · With vise & tools · 144 flies
$248.29
$1.72 a fly
Bought separately $282.15 · you save $33.86
Includes Standard dry-fly hook · and 16 more
Every item in this kit · 17 items
Hooks & beads
- Standard dry-fly hook$35
Thread & wire
- Olive 8/0 thread$17.70
Materials
- Other material: Coq de Leon fibers, split$22.50
- Other material: Olive goose biot$22.50
- White pearl Z-Lon$10.50
- Olive superfine dubbing$18
Finishing
- Head cement$5.95
Tools
- Rotary pedestal vise$79
- Ceramic bobbin$14
- Fine-point scissors$16
- Whip finisher$9
- Hackle pliers$7
- Bodkin$5
- Bobbin threader$4
- Dubbing wax$4
- Canvas tool roll$12
Guide
- Printed recipe and tying stepsIncluded
The creator

How it was made
1 iteration led here; the saved one is marked
1 Saved
Remixes
7 steps back
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- Windblown Pearl Olive Mayfly Dunyou are here
No remixes yet — make your own version.
Where this came from
“make the wing look more disheveled so it doesn't have such an even cut”
fly pattern · made
0 — nothing entered the score yet, at the Derby's published weights, since . Views are not counted.
- blue-winged olive
- bwo
- mayfly dun
- dry fly
- olive
- pearl
- z-lon
- goose biot
- coq de leon
- trout
- spring creek
- size 16



