Streams Outside Yellowstone National Park
|.............................Fly Fishing Yellowstone National Park
Destinations Outside Yellowstone National Park Series
Madison River - Slide Inn to Lyon Bridge - Salmonfly Hatch - 2
When the salmonfly hatch first starts, the trout quickly become aware of it. The large
salmonfly nymphs, which are three years old, begin their migration to the banks where
they crawl out of the water to hatch. Some crawl up on boulders in river but the great
majority crawl out on the banks.
The salmonfly nymphs are huge relatively to the size of normal mayfly and other
smaller stonefly nymphs. This image should give you a good idea of the size. It is even
larger than you may think it is from looking at the picture. I have very large hands.
It doesn't take many of these large nymphs to get the trout full. They are not very
difficult for the trout to catch because they crawl on the bottom directly exposed to the
trout. During the early morning and late evening hours you can see these nymphs in
the water crawling along the bottom towards the banks. After the hatch has been
underway a day or two, you can see thousands of the empty shucks scattered along
the banks and on boulders and rocks. The bushes will become cluttered with mating
stoneflies shortly after the hatch starts.
This tends to lead anglers into tying on an imitation of the adult or a dry fly instead of
a nymph. This usually results in a lot of casting and no trout because the large flies are
either in the air flying or in the bushes along the banks. Until the females begin to
deposit their eggs on the water, anglers should be fishing imitations of the nymph.
About three days after the hatch starts at any one location, imitations of the nymph
may become ineffective. The trout may simply be full of them and not take your fly. In
that event, you should move up stream two or three miles or more and fish the nymph.
As I said before, the hatch progresses upstream as much as a few miles a day
depending on the weather. That doesn't mean that it starts and ends each day in a
particular location. It may be a couple of weeks in any one location before all the
females return to the water to deposit their eggs. Tomorrow I will get into the details of
fishing the nymph imitation of these large stoneflies.
Copyright 2008 James Marsh