Dry FliesCDC&Elk Flash (opal)
Hans Weilenmann's CDC&Elk Flash works opalescent Flashabou into the abdomen of the classic CDC and elk hair combination, wrapped flat over a bare shank beneath a natural CDC thorax. The mule deer wing and head keep it floating and durable, while the added flash gives pressured fish an extra trigger.
Spring, Summer, Fall
Beginner
Trout
Feb 2026
Overview
Weilenmann built this as a flashier take on his own CDC&Elk, swapping a dubbed body for opal Flashabou wrapped directly over the hook shank. The natural CDC thorax still supplies the trigger-rich movement the original is known for, and the mule deer wing and head handle flotation and visibility. It's worth reaching for when plain CDC&Elk stops drawing looks on heavily fished water or in low light.
Where to Buy This Fly
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Materials
- Hook:
- Grip 14723BL #14
- Thread:
- Benecchi 12/0, tan
- Abdomen:
- Flashabou strand, opal - wrapped flat over bare shank
- Thorax and strands:
- CDC feather, natural
- Wing and head:
- Mule deer
Behavior & Presentation
Natural Behavior: Caddis skim the surface to lay eggs, wings catching light as they dip and rise repeatedly. Flash signature becomes a feeding cue.
Where Trout Eat It: Fish target flashing caddis in riffles, runs, and along seams where egg-laying activity creates consistent visual triggers during daylight hours.
How to Fish It: Dead drift with minimal mending. The flash element triggers takes in broken water and low light without spooking selective fish.
Best Water: Work seams with egg-laying activity, riffle edges, runs with varied current, and current breaks.
Strike Type: Watch for confident rises or aggressive takes as fish react to the flash and movement signature.
Fishing Strategy
Rigging Suggestions: Use a 9-12 foot leader tapering to 5X tippet for delicate presentations. Apply floatant to the body and hackle.
Seasonal Timing: Most effective during peak feeding periods at dawn and dusk. Water temperatures between 45-65°F typically produce best results.
Pro Tips: The opal flash provides a subtle strike trigger without spooking selective fish. When standard CDC&Elk patterns are refused, the flash variant often produces takes.
Entomology
Caddisflies skim the water surface to lay eggs, their wings catching light as they dip and rise in quick succession across riffles and runs. Fish become attuned to the flash and movement signature of egg-laying adults that represent consistent feeding opportunities during warm afternoon hours.
- Order
- Trichoptera
- Common Name
- Caddisfly
- Organism Type
- insect
- Life Stage
- adult
