|....................... .................... ...Fly Fishing Yellowstone National Park
New KISS Bug Series - Part 16
The Blue-Winged Olives:
If the water and air is cold, the Blue-winged Olive duns will ride the water for a relatively long time. Often
the problem with early and late season hatches is that the trout are also cold and as a result, are not very
active. It's much easier for them to take the nymphs and emerging nymphs in the surface skim than it is the
duns. This most often happens in the early season. Later on in the season when the water is warmer, they
tend to take the duns much better. During the Fall hatch, unless the weather has turned extremely cold, the
dun imitations usually work great.
The Blue-winged Olive hatches can be so prolific on some Yellowstone streams that the water is covered
with the little olives. Getting the trout to take your imitation over the real ones can be a challenge. The best
procedure under these conditions is to select one fish and present your dun imitation to it in a timely
If conditions are right, the Blue-winged Olive dun pattern, or dry fly, can be an exciting way to fish during
the hatch. If you find that the trout are not responding to your dun pattern very well and you are not
determined to fish the dry fly under any conditions, you should change back to an emerger pattern. It
shouldn't take long to determine this during a good Blue-winged Olive hatch. The trout will usually line up in
the current seams when they are feeding on the duns. You should concentrate on drifting your dun pattern
drag-free in the current seams. This is not exactly easy to do under some circumstances. Getting a drag
free drift is especially difficult in smooth or slick water. The smooth, slick water found in some streams can
consist of strong, conflicting currents.
If you make a few bad cast over a trout (sometimes just one bad cast) then you may have to move to
another area. Generally speaking, long light leaders and tippets are necessary in the smooth water. Nine
to twelve foot leaders and 6X tippets are not uncommon under these conditions. In pocket water, you can
get by with heavier leaders and tippets, shorter cast and maybe even a few mistakes.
Everything relative to the emerger presentation applies to the dun imitation, except it is fished dry on the
surface. This is very demanding trout fishing in many smooth water situations. Even in pocket water, the
dun will float down the current seams adjacent to the slow water areas where they hatch. Sometimes they
are trapped in shallow, calm areas within the pockets and calm areas of water along the banks of the
stream. In either case, this requires a longer and lighter than normal leader.as well as a good presentation.