Cul de Canard; what exactly is it and do you have enough?
What do we know about CDC feathers? At the very least you’ve probably heard or read about the floating qualities of CDC feathers, but why do they float so well? And are there other applications?
In French, Cul de Canard translates to duck bottom, or duck’s butt. What also happens to be near the duck’s bottom is the preen gland which produces preen oil. This oil is used by ducks and other floating birds to spread on their feathers to remain more buoyant. The CDC feathers are found around the preen gland and have the highest concentration of preen oil. Hence the superior floating quality. This is also why we don’t use regular floatants on CDC flies; the floatant will cancel any buoyancy offered by the preen oil. A couple false casts is all you need to effectively dry out soggy CDC feathers. You can also switch flies to dry the wet one or use a desiccant powder made specifically for CDC application. Often times flies tied with CDC perform their best when a bit water heavy. On dries and emergers the wet CDC holds that fly body in the water’s surface. Insert fish explosion...now!
Now let’s dive under the water’s surface to see what else these magical feathers can offer. When you look at the fibers of a CDC feather you notice many barbules. These barbules act as little hands which clutch and trap tiny air bubbles. Under water as these bubbles cling to the side of the fly or trail off behind the fly they replicate the escaping gasses exhibited in bugs that are hatching or switching cases or progressing through a larval or pupal stage. This in turn triggers a predatory response in your target fish. The small offering of air holding barbules can make all the difference between fishing and catching, especially on tail waters or over highly educated fish.
Of all the wonderful, natural materials we can put on a hook to catch fish the CDC feather is one of my favorites. You can strip it to tie in a clump, wrap the feathers directly on the hook or even slip some CDC into your favorite dubbing loop. There really is no bad way to incorporate some. Try adding some CDC to your commonly fished patterns and be prepared to meet some new fishy friends you may have missed before. CDC is the bee’s knees. Well, duck’s butt.