.......................  ....................  ...Fly Fishing Yellowstone National Park
New KISS Bug Series - Part 41

Little Yellow Stoneflies

The Little Yellow Stoneflies are often called Yellow Sallies. Even some species of the Little Green stonflies
are called Yellow Sallies. It is the Blue-winged Olive common name of the stoneflies. If it is yelllow and a
stonefly that isn't large, in many angler's mind it is a Yellow Sally. You can't say they are nuts because a
common name of an insect is what anyone calls it. That's one of the reason for scientific names. They
eliminate the confusion caused by anglers using common names.

The Perlodidae family
Isoperla genus includes the bilineata species that is called the Yellow Sally; however,
many other yellow stoneflies are also given the same common name. At least that's what some of the fly
fishing writers contend. They are found nationwide and are quite common in many streams. Trout can be
taken on the nymphs and female egg layer imitations.

Stonefly nymphs are far more important than the adults from a fly-fishing standpoint. They represent a
large part of the diet of the trout. There are (9) nine families of stoneflies found in trout streams. Of all the
families present, the Perlodidae and Peltoperlidae families usually represent more than any of the
others in terms of sheer numbers.

The species of the Periodidae family, the most important one, differ in size but their basic color and shape
is very  similar. Species of the Peltoperlidae family are shorter and more rounded than the Periodidae
species but all the species within the family are very similar in shape and basic color.

Like all stoneflies (with rare exceptions), the Little Yellow Stoneflies crawl out of the water to hatch. The
nymphs are much more susceptible to being eaten by trout when they migrate from their normal locations
down in between and under rocks on the streambed to the banks 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 to subject to being eaten. They don't show up that regular in drift samples;
however, and I doubt it is a frequent occasion. Behavioral drifts, which usually occur under low light
conditions or during the night, don't have substantial numbers of stonefly nymphs.

There are so many different species of stoneflies including the Little Yellow species, there is a hatch
occurring more often than you would think. The bottom line to this is that your odds of success are good if
your are fishing stonefly nymph imitations most any time. Trout eat them whether they are hatching or not.
Of all the Little Yellow species, the Yellow Sallies provide the best opportunity for anglers. They often
deposit their eggs during the daytime, whereas many other stonefly species do so during the evening
Copyright 2012 James Marsh
Little Yellow Stoneflies:
Availability to trout:             
Hook Size:                          
Type of water:                    
Emergence time:                
Duration of hatch period:

Perlodidae family species
Most all fast to moderate water streams
Late Afternoons, mostly evenings