Published Aug 19. 2006 - 17 years ago
Updated or edited Nov 12. 2020

CDC Mayfly

A small mayfly, which may be (mis)taken for a dun during the sometimes the concentreted hatches on late August and Septemper evenings. It uses a hollow extended body, parachute hackle and wings of cdc stems to float high.

One day I was given this fly by a friend, but I only got one.

The finished fly

I found it nice and convincing and decided to put it away until tying time.
During the summer 2006 I fished it in Tuscany - Italy and lost it.

A few weeks ago my job took me to Jutland where I had a meeting close to some danish streams. I spent an afternoon with Ripley Davenport (known by regulars in the GFF forum and Pix section) at the banks of one of them. As it got darker we witnessed one of the most hysteric hatches I have ever seen. Duns crawled up and down our waders. Nymphs were emerging through the surface and duns penetrated the film to get to the bottom.

Photographing in the sparse light was difficult, but we got some pictures, which inspired me to take up this pattern again - before it escaped my memory.

I know the tail and color is not realistic in this specimen, but this is a generic pattern and it will probably show it's effectivness just the same.

Stream curve

CDC May Fly
Pattern type: 
Dry fly
Dry Fly, ie. Partridge SLD.
Extended may fly body.
Dry fly dubbing, light colurs mixed with a little bit of dark coloured.
Brown or grizzle, parachute style.
Two bottom parts of cdc feathers.
Darker dubbing mix.
Skill level/difficulty: 
  1. Make 10 extended mayfly bodies/tails or look through your materials to see if you got some pre-made ones.
  2. Attach the thread.
  3. Tie in the body/tail., Ajust the length.
  4. Tie in the two cdc-feathers. Secure them and tie them in up-right position.
  5. Stabilize the wing base
  6. Dub the body behind the wing.
  7. Tie in the hackle.
  8. Turn the hackle around the wing base.
  9. Secure the hackle making the thread follow the hackle 4-5 times.
  10. Dub the front body and head.
  11. Whip finish.
  12. Ajust the wing length.
  13. Tie 9 more.
  14. Go fishing.

Ripley is being challenged...

Hatching on the waders

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Top view

Front view.

Read more about how to make extended bodies here


Nice fly! As my pra...

Nice fly! As my practice shows there is no use to make such complicated steps. I use only 2 cdc feathers for both extended body and the wing. One disadwantega - it work only for one trout and the is totally destroyed, but for many graylings)


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