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BWO Comparadun
A emerger, tied #18–22, carried year round. It is tied against 2 named insects in this book — March–June and September–November.
A flush-floating emerger on a standard dry-fly hook in sizes 18 through 22, tied with olive 8/0 thread. A trailing shuck of olive Z-lon takes the place of a tail, the body is olive superfine dubbing, and the wing is coastal deer hair fanned 180 degrees over the body. There is no hackle, so nothing holds the fly up off the water and the body sits down in the film — which is where the natural is. It is tied against the Blue-Winged Olive, Baetis spp., out March through May and again September through November, in water between 38 and 58 degrees. Baetis emerge in the film and the fish know it, which is why this dressing is worth having on when a trout has just looked at a fully hackled dun and refused it. It is carried all season and fished for trout.
- #18–22Hook size
- emergerType
- AllSeason
- 2Hatches matched
What it looks like
A drawing, not a photograph, and not traced from one. Its proportions were read off 5 independent reference photographs of the pattern and written down as 5 measured characteristics — wing angle, tail length against the shank, how far a hackle fibre reaches — every one of which had to hold across more than one of them before it could be drawn. What survives across many photographs of a fly is the fly.
What it imitates
Each of these is the same hatch record the app's own panel reads, so a pattern recommended on a river card in the app is recommended for one of the insects below.
- Blue-Winged Olive Baetis spp. · March–May and September–November · 38–58°F · #16–22
- Large Blue-Winged Olive Drunella cornuta · May–June · 50–64°F · #14–16
Tying recipe
In tying order. This dressing is the standard one — these patterns have been in the publicrecord for decades — and materials substitute freely: the proportions and the silhouette are the pattern, not the brand of dubbing.
| Hook | Standard dry-fly hook, sizes 18–22 |
|---|---|
| Thread | Olive 8/0 |
| Tail | Trailing shuck of olive Z-lon |
| Body | Olive superfine dubbing |
| Wing | Coastal deer hair, fanned 180° over the body |
| Hackle | None |
When to fish it
No hackle, so the body sits in the film. This is the fly for a fish that has just refused a dun.
Carried all year. The insects it matches are active march–june and september–november, in water from 38°F to 64°F.
Target species
- Trout
Rivers it fishes well
Rivers with a page here that sit in the regions where the insects this pattern imitates are recorded. It is a claim about coverage, not a report of a fish caught.
- Au Sable River northern lower Michigan · July mean 72.1°F
- Catawba River the North Carolina mountains · July mean 76.7°F
- Jackson River the Virginia mountains · July mean 66.3°F
- Muskegon River northern lower Michigan · July mean 71.0°F
- Escanaba River the Upper Peninsula · July mean 68.3°F
- Saint Croix River northern Wisconsin · July mean 77.2°F
- Smith River the Virginia mountains · July mean 51.9°F
- Tygart Valley River the Virginia mountains · July mean 74.6°F
- Kalamazoo River southern lower Michigan · July mean 71.3°F
- Aaron Creek the North Carolina mountains · July mean 76.7°F
- Aaron Run the Virginia mountains · July mean 77.1°F
- Aarons Run the Virginia mountains · July mean 74.2°F
Related patterns
Same type of fly, or tied for the same insects.
- RS2 emerger · #16–24 — The emerger that saves a hatch you cannot otherwise crack. Fish it in the film.
- Cahill Comparadun emerger · #14–18 — No hackle, deer-hair wing, body in the film. What to change to when the fish start refusing the standing dun.
- LaFontaine Sparkle Pupa emerger · #12–18 — The gas-bubble pupa. Fished rising through the swing, which is how caddis actually emerge.
- Little Black Caddis Pupa emerger · #16–20 — Dark body, sparse soft hackle. Swung through the tail of a run in April, which is where the naturals are going.
- Sulphur Comparadun emerger · #14–20 — No hackle, sits in the film. What to tie on when duns are drifting past untouched.