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Sulphur Comparadun
A emerger, tied #14–20, a summer pattern. It is tied against 3 named insects in this book — May–July.
An emerger with no hackle at all, built to sit down in the film rather than above it, which is the answer when duns are drifting past untouched. It is tied on a standard dry-fly hook in sizes 14 through 20 with yellow 8/0 thread: an amber Z-lon shuck for a tail, a body of pale yellow superfine dubbing, and a wing of light deer hair fanned across the top to hold the fly in the surface. Nothing supports it below the waterline, so it rides in the meniscus the way a struggling insect does. It is tied against the sulphur, Ephemerella dorothea and invaria, hatching May through July in water from 52 to 68 degrees, and the pale morning dun, Ephemerella excrucians, in June and July from 50 to 65, and it serves for mayflies generally. Fished through the sulphur emergence, in the film, on flat evening water it outfishes the dun most nights. A summer fly for trout.
- #14–20Hook size
- emergerType
- SummerSeason
- 3Hatches 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.
- Little Sulphur Ephemerella dorothea · May–July · 50–62°F · #16–20
- Pale Morning Dun Ephemerella excrucians · June–July · 50–65°F · #14–18
- Sulphur Ephemerella invaria · May–July · 52–68°F · #14–18
It is also tagged for mayflies generally.
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 14–20 |
|---|---|
| Thread | Yellow 8/0 |
| Tail | Amber Z-lon shuck |
| Body | Pale yellow superfine dubbing |
| Wing | Light deer hair, fanned |
| Hackle | None |
When to fish it
Sulphur emergence, in the film. On flat evening water this outfishes the dun most nights.
A summer pattern. The insects it matches are active may–july, in water from 50°F to 68°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.
- Pheasant Tail Nymph nymph · #12–22 — The mayfly nymph. Beadhead or not, size 16, and half the trout in the world have eaten one.
- Rusty Spinner dry fly · #14–20 — Almost every mayfly spinner is rust-coloured. This covers the last hour of light.
- BWO Comparadun emerger · #18–22 — Flush-floating. Baetis emerge in the film and the fish know it.
- 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.