|....................... ......Fly Fishing Yellowstone National Park
Fly Fishing Yellowstone - Pale Evening Dun - Emergers
The Pale Evening Dun mayflies hatch in the late summer and early fall months
in Yellowstone National Park depending on the weather and elevation of the
stream. Hatches at very high elevations can come earlier than those at the lower
elevations because the water starts cooling down earlier as a general rule.
Hatches normally take place in the mid to late afternoons if the weather is cool.
Most of the time these mayflies hatch the weather will be cool, otherwise the
water temperatures would not be quite low enough for the hatch to occur.
As mentioned yesterday, the nymphs migrate from the fast water to the slower
parts of the stream just prior to hatching. This is only a few feet at the most.
They usually move to shallow water near the banks of small pockets where the
water is calmer than the surrounding faster water or pockets created by
boulders and large rocks. The Pale Evening Duns normally hatch in water
between 50-55 degrees F. but remember this is not a early summer hatch when
the water warms up to that temperature. They start to hatch when the water
cools down to that temperature. In Yellowstone this can be anywhere from mid
August to October depending primarily on the altitude but also the varying
Our "Perfect Fly" Pale Evening Dun Emerger flies can be presented on the
swing from the faster water to the shallow water near the banks. You want to
allow the fly to drift in the surface skim by its CDC wing. An up and across
presentation usually works best for this.
We have two types of emerger patterns for most all mayflies that hatch in the
water including this one. One is a CDC winged version on a curved hook
designed to float in the surface skim. The other is a trailing shuck emerger
imitating the nymphal shuck still stuck to the tail of the newly emerged dun. This
one is also designed to float in the surface skim. Both can be presented on the
swing in the same manner.
Copyright 2009 James Marsh