Fishing the Blue Winged Olive Dun

The Blue-Winged Olives that are found in most of the streams in the USA are of the Beatis genus of the Baetidae family of mayflies. These duns have two tails and a very tiny hind wing. There are a few species that do not have a wing whatsoever, but this is a minor variance. Since they are called blue winged olive flies, you can expect the body to be green or olive color with gray highlights. The wings are a mild blue or even could be called a shade of gray. 
 
Presentation:

The dun flies away to nearby streamside vegetation as soon as its wings are dry enough to fly. But the duns will linger on the surface of the water until their wings dry out and you will usually see many of them doing that. In this case, your fly imitation will have some heavy competition, so it might be better to locate a feeding trout and entice him to take your fly. This is opposed to finding schools of trout feeding on the flies.

 

You will find the trout just sipping the emerging duns and cripples and therefore you need to be gentle in your delicate presentation.  Use a four weight or lighter line coupled with a 2 or 3 foot leader and a five X or six X tippet for a total of 10 or 12 feet. Fish the dun on the surface as a dry fly in smooth water or even pocket water. Let the fly float down the current seams to the slow water areas.

 

Sometimes the duns will be trapped in shallow calm areas in pockets of water along the banks or behind large boulders in the stream. This requires a delicate patient approach but it will be rewarding.