.......................  ......Fly Fishing Yellowstone National Park

06/26/09


Fly Fishing Yellowstone - Little Yellow Stoneflies

am not certain just how many exist in Yellowstone National Park. The good thing
about it is that it makes little difference. Little Yellow Stoneflies belong to the
Periodidae family of stoneflies. They are properly called Little Yellow Stoneflies. I
mention that only to point out that often anglers incorrectly refer to just about
These are a lot of different species of Little Yellow Stoneflies in Wyoming but I
am not certain just how many exist in Yellowstone National Park. The good thing
about it is that it makes little difference. Little Yellow Stoneflies belong to the
Periodidae family of stoneflies. They are properly called Little Yellow Stoneflies. I
mention that only to point out that often anglers incorrectly refer to just about
any of the species of Little Yellow Stoneflies as "Yellow Sallies". The Yellow
Sallies are species of the Perlodidae
Isoperla genus of stoneflies or the
Stripetails.

As with any stonefly, the Little Yellow Stonefly nymphs are far more important
than the adults. Like all stoneflies (with rare exceptions), the Little Yellow
Stoneflies crawl out of the water to hatch. Trout eat the nymphs when they are
exposed migrating from their normal hideout down between and under the rocks
on the bottom of the stream. They can't very well hide when they are crawling
across the bottom to the shoreline or large rocks or boulders to crawl out to
hatch.

When there is no hatch taking places, the stoneflies are basically safe from the
trout. It is not unusual for one to become dislodged and subject to being eaten.
They don't show up that regular in drift samples; however, and I doubt it is a
frequent occasion.

The most popular species are the Yellow Sallies. They hatch during the daytime.
Many other smaller stoneflies hatch during the evenings. There are some
species that hatch during the hot summer months that do so in the evenings.
They also provide a good opportunity for anglers  

Copyright 2009 James Marsh