On the freestone streams in the Upper Midwest we have several larger mayflies that hatch, such as Hexagenia limbata (Hex hatch) and Ephemera simulans (Brown Drake hatch). For these hatches I prefer to tie an extended body dry fly pattern for imitating these large mayflies on the water. The extended bodies seem to float higher and longer which really helps when darkness falls on the water and it becomes difficult to see your fly or to tie on a new fly.
For extending the fly body I like to use 30 lb. monofilament. It’s light weight. yet stiff enough to wrap the thread and body around it without too much hassle. For the example below I am going to tie a Hex extended body comparadun dry fly pattern that I have used for years.
After wrapping the thread on the hook shank I use the thread to secure a fairly long piece of 30lb. mono to the hook. I like to use a longer strand of monofilament so I have something to grab. Eventually I will trim off the excess monofilament.
Next I tie the tail fibers to the hook shank making sure the tail extends past the hook far enough. The monofilament will probably be as long as the tail, which is fine. We will trim it later. For my Hex pattern I like to use ginger colored Microfibetts because they are longer and more durable.
Next, reverse the hook 180 degrees and stick the hook point into the vise jaws I find it is much easier and faster to tie the extended body on the monofilament with the hook reversed..
Now I wrap the thread around the monofilament and tail fibers as far back as I need too for making the extended body. This is where leaving some extra monofilament comes in handy. It gives you something to grab on too when needed. Plus, the extra helps make sure the thread doesn’t slide off the end of the monofilament.
Now twist the dubbing onto the thread and wrap around the monofilament towards the bend of the hook. For my Hex dun pattern I like to use tannish colored dubbing, or tannish-yellow dubbing. (It technically doesn’t matter what color you use for the dun because it will be pitch black out when you are fishing the Hex hatch and the fly’s silhouette and your presentation are far more important than color in the dark.) Once I have finished wrapping the dubbing on the monofilament up to the hook bend I reverse the hook again in the vise.
At this point I usually trim off the excess monofilament that extends beyond the body. Then I move my thread forward and create the comparadun wing using deer hair that is approximately the length of the entire body.
After the deer hair wing is secured wrap the thread back towards the hook bend and add more dubbing to finish the body. Recently I have started to add one dry fly hackle immediately behind the deer hair wing. I first saw this done last summer by Bob Jacklin out in West Yellowstone. He uses this technique for his Green Drake comparadun dry fly pattern. I feel the hackle gives the fly’s deer hair wing a better overall visual appearance and it adds some extra floatability and durability to the fly, which can be really important when fishing these large flies in the dark. After adding a few wraps of the hackle I secure the feather and trim. Then I wrap the thread in front of the deer hair, add some dubbing and build it up to help keep the deer hair slanted straight up or slightly backwards towards the hook. Last, whip finish.
The last thing to do is trim all the hackle underneath the hook so the fly will float flush on the water
Here is the same pattern except without adding the hackle…
The extended body dry fly pattern works great when the Hex duns are on the water. Just be sure to hold onto your rod real tight when you hear that big gulping noise out in front of you in the dark shadowed waters.