These are small, slim profiled stoneflies with relatively long antennae and tails. They are usually close to a
hook size 18 but some are closer to a size 16. Only a few species get larger than that. We haven't found any
species in the Smokies that get any larger than that. We have found one species, not very common, that is a
little smaller than an 18 hook size.
This one is as dark as any we have found in the Smokies. Most of them are brown and some even a light
brown color depending on the particular genus and species. The adults seem to always be much darker than
A very old article I wrote about wnter stoneflies for our fly fishing Great Smoky Mountain Website.
Yesterday, was the first time in a long time that I can remember catching trout on the surface on our imitation
of the adult Winter Stonefly. I spotted several hook size 16 and 18 adults on the rocks, road and bushes. As
best I could determine, the different sizes were not different species, rather the male and female genders.
The were mostly a very dark brown, almost black color. The bottom of our imitation is black foam but the
wings are made of dark brown raffia. The water was unseasonably warm and even though I didn't see any
trout feeding on the surface, I tied on an imitation of the adult and managed to catch two rainbows in about
15 minutes of time. I called it quits on that and went home. I had strict instructions from Angie not to wade
without I was with someone. I knew she would see the wet waders and I wouldn't get by with it, so I hop
skipped around the clear areas along the banks.
I had spent the past couple of hours walking the banks fishing a Winter Stonefly nymph. I didn't see any
stoneflies crawling out of the water, probably because it was too early in the day for that. I did catch one nice
brown about 12 inches long and one small rainbow on the nymph but all in all, it was a slow go.
Sometimes, when these stoneflies hatch the trout will not rise to the surface to eat the adults. The reason for
this is often when the adults are depositing their eggs the water is too cold for the trout to feed on the
surface. If the water temperature is less than 42 degrees F., they probably won't feed on the surface at all.
Usually when the little Winter Stoneflies are hatching, it is that cold and often even colder. If the water warms
up some and the stoneflies hatch, then the trout usually feed on the egg layers on the surface.
If you are fishing during the winter, you should always keep this in mind and you should always be prepared
to fish the egg laying stage of the hatch. Just because you see the adults doesn't necessarily mean they will
be depositing eggs. These stoneflies can live for a few days and they don't begin to deposit their eggs until
a certain amount of time passes. When the females do deposit their eggs, they die.
You should normally fish the dry fly adult only when you observe the stoneflies depositing their eggs on the
surface of the water; however, I violated that rule of thumb yesterday, and was successful. Egg laying
usually occurs during the afternoons. It doesn't always occur in riffles. These little stoneflies often deposit
their eggs in slow moving water near the ends of the pools. It depends on the particular species of
Just keep your eye out for them to deposit their eggs on the days you find them crawling around on the
banks and rocks. If they have hatched, they are going to lay their eggs within a few days at the most and if
the water isn't too cold, they will usually eat the dry fly adult imitation..
Most of the aquatic insects that live in the streams of most tout streams have a one-year life cycle. There are
very few exceptions to this. For example, a few species of large stoneflies live a two- year life cycle. This
means, depending on the type of metamorphosisthey, hatch from an egg, live in their larval stage of life for
most of their life, and emerge into the adult stage of life from their nymphal or pupal stage within a year.
Midges and caddisflies emerge from pupae. Mayflies and stoneflies emerge directly from nymphs into adults.
During the winter months of most troot steams, the water is full of aquatic insects in their larval stage of life.
The majority of these will emerge into adults by the end of June or July, depending on the location. Most of
the others will emerge into adults during the following months. The only exceptions are those that live a
two-year life cycle. With the exception of a few terrestrial insects that make up a very small part of the trout's
diet during the year together with a few marine species such as sculpin and minnows, a very few species of
crustaceans, these aquatic insects represent the great majority of the food trout eat. They eat the aquatic
insects year-round except for the short period of time the insects exist in the egg stage of life. The great
majority of the aquatic insects are eaten in their larval stage of life. A few are eaten as pupae and in their
adult stage of life.
One of the most common groups of aquatic insects are the stoneflies. There are nine families of them and
species from at least some these nine families live in most streams of most trout streams. One of these is the
Capniidae family of stoneflies. They represent one of the few species of aquatic insects that emerge and are
available to the trout when the water is extremely cold.
Although species of the Capniidae family of stoneflies are classified as "Little Brown Stoneflies" for the most
part, they are almost black or various dark shades of brown. Most anglers refer to them as "Little Blacks" and
some as "Little Winter" stoneflies. They are also called Snowflies. They get that name because they are easy
to spot crawling around on the snow due to the contrast. Most stoneflies live a one=year life cycle.There are
exceptions to this. For example, some species of large stoneflies live a two- year life cycle. This means they
hatch from an egg, live in their larval stage of life for most of their life,nd emerge into the adult stage of life
from their nymphal or pupal stage depending on the type of metamorphosis within a year. Midges and
caddisflies emerge from pupae. Mayflies and stoneflies emerge directly from nymphs into adults.
by James Marsh
Copyright 2020 James Marsh
February, 2020 Issue
Winter stonefly nymph
Winter stonefly adult