....................... ......Fly Fishing Yellowstone National Park
Fly Fishing Yellowstone - Small Western Green Drakes (Flavs) -Nymph
The Small Western Green Drakes, called "Flavs", are crawler nymphs. They prefer moderate currents. They cannot live in still or slow moving water. Many of the streams in Yellowstone National Park offer the perfect habitat for them.
Like many crawler nymphs, when they get ready to hatch, they move out of the faster water of the runs and riffles to nearby slower water. This may be calm pockets in pocket water or the slow side of current seams in smoother water. Trout feed on them with ease during this movement. Its by far the best time to catch trout on an imitation of their nymph. The nymphs emerge in the surface skim and it is very easy for the trout to eat them when they are accenting to the surface to hatch.
Presentation: A few days prior to the hatch and in the mornings during the hatch prior to their emergence, you can use the standard up and across presentation using a strike indicator. Fish the our "Perfect Fly" Small Western Green Drake Nymph near the bottom on the slow sides of the current seams, in calmer pockets behind boulders and in the slower water along the banks in fast moving pocket water. You will need to weight it fairly heavily using non-toxic weight.