"Certain dry flies have a specific characteristic that tend to capture the attention of difficult trout, but this one has three. With a biot body, Realistic Mayfly Wings, and cdc at the thorax, there is lots going on with this pattern. In this video, I tie a fly to represent the Blue Wing Olive (BWO) mayfly, yet the beauty of the Biot Body CDC Dry Fly is that it can be modified to represent many other mayflies. One additional benefit of this fly is that it can both represent the adult and emerger stages of mayflies, yet another reason why it can be so effective.