BWO Cripple

When fall returns, so do the hatches of Blue Winged Olives (BWO). As with most fly patterns, this BWO cripple is an adaptation of many proven patterns—and possibly something I unknowingly borrowed from another fly tyer. That being said, I chose this pattern due to its ease of tying and effectiveness. It can be tied in a variety of sizes and should prove effective just about anywhere BWOs are found hatching.

Hook: Dai-Riki #135 size 16-22
Thread: UTC Ultra Thread 70 Denier olive
Trailing Shuck: Tan or light brown Zelon or Antron
Wing: Dark natural Cul de Canard (CDC) feathers
Thorax: Light olive Superfine dubbing

1. Attach thread with a few wraps near the eye of the fly and attach a few strands of Zelon or Antron.
2. Loosely wrap thread toward rear of fly while carefully holding the shuck material on top of the hook. On this emerger hook, I like the body to extend behind the barb about one eye length.
3. Trim the shuck to about the hook length and loosely wrap thread stopping about 2/3 of the way up the shank.
4. Select one to three CDC feathers and align the tips, then measure the feathers to about the length of the hook. Secure CDC to hook with tips facing toward the front of the hook over the eye.
5. Trim butt ends of CDC to about 1/4 of hook shank length.
6. With thread still at the CDC tie-in point, dub in a small thorax of fine dubbing.
7. Advance thread to the front of the CDC wing and just behind the hook eye. Whip finish or half hitch. I also recommend a thin layer of head cement on the thread-wrapped body and head.

Note: the colors and sizes of this pattern can be manipulated to cover a variety of mayflies, so feel free to experiment.

Jimmy is the manager of Gallatin River Guides in Big Sky. Visit