Dry FliesFlavio
Hans Weilenmann's Flavio is a low-riding emerger for mixed mayfly and caddis hatches, built around a trailing amber Antron shuck and a dyed-olive goose-biot abdomen. A natural CDC and grey polypropylene wing lies close to the water instead of standing upright, matching insects caught mid-emergence. Anglers reach for it when duns or emerging caddis are stuck in the surface film and fish are refusing full dries.
Spring, Summer, Fall
Intermediate
Trout
Feb 2026
Overview
The pattern layers an amber Antron and lemon woodduck shuck behind a dyed-olive goose-biot abdomen, then builds an Argentinean hare thorax and head for a buggy, segmented profile. Its CDC and fine grey polypropylene wing sits low rather than fully upright, and dark-olive Whiting Brahma hen or brown partridge legs splay in the surface film. That construction reads as a mayfly or caddis still tangled in its nymphal or pupal skin, a stage trout target because the insect cannot yet fly. It suits slower currents, back-eddies, and stillwater margins where emergers hang in the film during spring and summer hatches.
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Materials
- Hook:
- Umpqua U203 #14, or any longshank curved hook
- Thread:
- Benecchi 12/0, olive
- Shuck:
- Antron, amber; Lemon woodduck barbs
- Abdomen:
- Goose biot, dyed olive
- Thorax:
- Argentinean hare, dyed olive
- Wing:
- CDC, natural; polypropylene (or fine antron), grey
- Legs:
- Whiting Brahma hen saddle, dyed dark olive (or brown partridge, dyed olive)
- Head:
- Argentinean hare, dyed olive
Behavior & Presentation
Natural Behavior: Exhausted adult caddisflies drift helplessly after mating flights, their wings splayed and bodies spent on the surface film. The parachute CDC wing tips and dubbed thorax create a low-riding profile suggesting the vulnerable, motionless posture of spent Trichoptera in smooth glides.
Where Trout Eat It: Trout sip emergers in Great Lakes tributary surface film, concentrating in smooth glides with visible post tracking.
How to Fish It: Float parachute design dead drift while CDC wing tips add natural movement, using post for visibility in choppy conditions.
Best Water: Fish pool tail-outs with glassy surface, slow inside bends with back eddies, and spring-fed sections with uniform flow.
Strike Type: Selective trout sip spent caddis with subtle dimpling rises or confident takes; observe the rise form and lift the rod when you see the take.
Fishing Strategy
Rigging Suggestions: Fish on 9-12 foot leader with 4X-5X tippet. Visible post allows use as indicator fly in dry-dropper rig while maintaining fish-catching capabilities.
Seasonal Timing: Most effective during hatches April through June and activity July through August when water temperatures range 50-65°F. Morning and evening feeding periods from 6-10 AM and 5-9 PM produce best results.
Pro Tips: Parachute hackle creates stable footprint in choppy water while CDC wing tips provide natural movement. Apply floatant to post and hackle for visibility and flotation in varied conditions.
Entomology
Adult caddisflies dance and hover above the water before landing to deposit eggs, then drift helplessly on the current when exhausted from mating flights. Fish have learned to capitalize on these spent insects because they offer protein-rich meals with minimal effort, drifting passively within easy striking distance.
- Order
- Trichoptera
- Common Name
- Caddisfly
- Organism Type
- insect
- Life Stage
- adult
