What do (does) the initals CDC mean when applied to a fly, such as Blue Winged Olive, CDC? Thanks, sorry I aint as smart as y’all, but I am tryin’!
CDC
… “Cul-de-Canard” posterior feathers from a bird, containing an incredible oil that helps keep it dry and water resistant.
…Cul de Canard… they’re basically duck butt feathers. I use 'em like hackle.
I never heard of 'em either til a couple years ago…ModocDan 
LOL!!! I was going to say “duck butt”, but wasn’t sure it would get past the sensors!!!
Did find CDC oil at Feather Craft, to apply like floatant. It’ll keep the flies dry and floating for hours!!
Cul De Canard (CDC) (French for “Duck bottom”) is the fluffiest down feathers from the bottom of a duck; they are very buoyant and are used when tying dry flies. They owe their buoyancy to their proximity to the ducks preen gland which secretes an oil distributed by the duck as a cleaning and waterproofing measure. It is unnecessary for the angler to add additional oil by way of floatant. Flies incorporating CDC are easy to dress and popular with anglers and trout alike.
Mark -
In a “blue winged olive, CDC,” the CDC part is likely the post in a parachute or perhaps used as wings in a hackled version.
CDC makes a great substitute for elk hair in a “caddis, CDC.” Harrop has a biot bodied CDC winged caddis that I think Betty will vouch for ??
Just a couple days ago, I fished a flying foam ant pattern where I used CDC for the wing. It was a killer pattern for brookies in a high mountain lake.
In a given pattern, the CDC designation might also refer to the dubbing. I haven’t tried using it as dubbing yet, but I’m saving the left overs as I tie other patterns with that in mind.
John
P.S. Get it from a hunter if you can, unprocessed in any way. There are two characteristics that contribute to it floating - the fibers and the preen oil. Processing will remove at least some of the oil, and might damage the fibers.
Mark: If you look at a plucked duck you will find a little bump on the back of the bird close to the rear. That is the preen gland where the cdc is located. From what I have been able to gather from reading various articles on cdc that the primary mover that causes the feather to float is not the oil but the composition of the feather itself. The little barbules trap air. Either way it is a fun item to tie with and if you send me your mailing address I’ll send you a small package of cdc straight from the duck or goose. They are unsorted and should give you an idea of what cdc is all about. Below is an article that is well worth reading on cdc.
Tim
http://www.danica.com/flytier/articles/cdc_types/cdc_types.htm
Hi Mark
There are some things that you are better off not knowing too much about. Sausage is on such thing. CDC feathers may be another----too much information about duck butts? I’m just happy knowing that they float like a beachball. 8T