Tim Cammisa of "Trout and Feather" has been fly fishing and tying for over 30 years. View his YouTube videos and more information at: http://www.troutandfeather.com
The Cahill Frenchie fly is a pattern that attempts to bridge the gap between jig nymphs and emergers, if such a place exists! At first glance, the inclusion of pale yellow dubbing may appear to be a hot spot or trigger, but there's more than meets the eye. Even better, this pattern can be varied to "match" various mayflies in the waters you fish. Before we get there, let's briefly investigate the fly's design, a variation of the ever popular Pheasant Tail fly.
As tiers push boundaries with Frank Sawyer's classic Pheasant Tail Nymph, fish have responded. Hot spots in the form of thread and synthetic dubbing is typically found in the thorax, and a more resilient fiber, known as Coq de Leon, is a favorite for the tail. The name "Frenchie" tends to include flies tied in this style, deriving from their popularity in Europe, especially in competitive fly fishing settings. The one common bond: Pheasant Tail, which resembles many nymphs found in our waterways.
Investigating the pattern, I wanted to continue the effective contrast, a point constantly driven home to me by Fly Fishing Team USA member, Josh Miller. However, instead of a hi-vis thorax, I thought about the mayfly life cycle, as a nymph emerges to a dun, or adult. During this transition, the adult sheds its nymphal skin, and many times fish key on this emergence, as it's a sign of vulnerability. The emergence takes place closer to the surface, so why the effectiveness of the pattern?
From my perspective, during the Light Cahill hatch, fish get accustomed to feeding on the nymphs, emergers, and adults, with the typical key colors being brown and pale yellow. Put the two together, and the Cahill Frenchie is born. Until trout can talk, we're going to have to stick with that rationale. ;-) Many mayflies go through a similar emergence, thus investigate those found in the waters you fish, then vary the thorax color in your patterns accordingly.
As mentioned in the "Trout and Feather" YouTube video accompanying this pattern, there are many ways that you can fish the fly, and tightline nymphing is a recommended method. Consider integrating this into your dry-dropper setup when Light Cahills are hatching, and to reduce weight, tie without the tungsten bead or try brass instead. Have fun tying and fishing the Cahill Frenchie!
How to Tie the Cahill Frenchie Fly
Hook: Hanak H450BL or Hanak H490BL; #14
Bead: 2.5mm slotted tungsten (gold)
Weight (optional): Five turns of .010 wire
Thread: Semperfli 12/0 waxed; Primrose or Yellow
Tail: Coq de Leon; medium pardo
Ribbing: Gold wire; extra-fine
Body: Pheasant tail fibers
Thorax: Delaware River Club dubbing or Rabbit Dubbing; pale yellow
1. Place tungsten bead on the hook, then secure hook into vise
2. *Optional - Add weight by placing five turns tightly against the bead (pushing towards eye)
3. *Optional - Start thread behind wire, then wrap over and through wire, securing to the hook; finish directly behind wire
4. Attach tailing fibers, approximately body length and a half, wrapping back to bend
5. Lash in ribbing, following by pheasant tail fibers (tie in by tips)
6. Wind pheasant tail fibers forward, securing behind bead
7. Counter wrap ribbing, securing behind bead
8. Dub tight thorax, then whip finish behind bead
9. Go fishing!