Slate-Winged Olive

NYMPH SIZE: 7-12 mm (1/4-1/2 in)

NYMPH COLOR: Brown with some dark olive

DUN SIZE: 7-13 (1/4-1/2 in) mm

DUN COLOR: Wing: smoky gray to dark gray. Body: olive, yellow-olive

SPINNER SIZE: 7-12 mm (1/4-1/2 in)

SPINNER COLOR: Wing: clear. Body: dark yellow-olive

OTHER CHARACTERISTICS: Nymph has beefy front legs with serrated edges, and three tails. Duns and spinners have three tails; the front edges of the back wings have rounded points.

About Slate-Winged Olives

Like their larger cousins, the green drakes (D. doddsi, D. grandis), slate-winged olives are crawler mayflies whose nymphs live in cold waters with moderate to fast flow. Nymphs are seldom available to trout until the emergence season, when they move to slower flows.

Because emergence is in slower water, your imitation needs to be reasonably accurate. So does your presentation: don't blind cast; wait until you see a trout rise to a natural, then gently, cast to that trout, leading it by a few feet.

Hatches are mid- to late-summer through early October. Hatches begin in the afternoon. Spinner falls can be important.

They are identical to D. flavilinea (flavs) in nearly every respect except that slate-wings prefer slightly cooler water; entomologists care about these differences, but trout and anglers needn't bother.

STAGE

PATTERN

SIZE/
COLOR

PRESENTATION

WHERE

Nymph

Poxyback Green Drake, Hares Ear, A. P. Nymph, Pheasant Tail

12-16/Brown

Indicator, Tight line, Shallow nymph

Riffles, moderate-fast runs

Emerger

Green Drake Cripple

12-16/Light olive

Standard dry fly

Runs below riffles, moderate-fast runs

Dun

Green Drake Paradrake, Parachute Hares Ear, Comparadun, Sparkle Dun, Thorax Dun

12-16/Light olive

Standard dry fly

Slow-moderate runs