Hatches Made Easy:

Winter Stoneflies
1/17/08:

Introduction:
Before we begin with what are called "Winter Stoneflies", lets review some basic
stonefly
information. Of the nine major families of stoneflies, four are
commonly called
“Little Brown Stoneflies”. They are the Capniidae,
Nemouridae, Taeniopterygidae and Leuctridae families. Now you don't need to
remember these names but you do need to remember this. Stoneflies of these
four families are usually small,
usually less than one-half inch long.
The “Little Brown Stoneflies” are not all brown. They range from brown to black.
Even though anglers may refer to some of them as “Little Black Stoneflies”, by
proper classification they are still considered to be “Little Brown Stoneflies”.
Also, what many refer to, as “Little Black Stoneflies” are just very dark brown
stoneflies but more importantly, one of these four families.
One good thing about stoneflies is that you don't have to know them down to the
species. In fact,
just knowing them down to the family level is usually all you
will need to know. That is because
they all behave very similarly. Also, you
only need to know two stages of their life. The nymphs and the adults.

The Winter Stoneflies are in the Capniidae family. There are several
species of the Capniidae family found in the Great Smoky Mountain National
Park. (see list below) The best hatches of these “Little Brown Stoneflies” usually
occurs during the winter and early spring months.  
Species of the Capniidae family are fairly easy to recognize in their adult stage
because they are the only ones in the group of “Little Browns”
that have long
tails
. Most anglers call them “Little Black Stoneflies” but they are also called
Winter Stoneflies” and sometimes, “Snow Flies”. They are usually small
stoneflies that range in color from dark brown to pure black and usually have
short wings. You may see them walking on snow near streams or they may be
found on bridges, rocks, or stream side vegetation.      
“Snow Flies” usually hatch from the middle of the day to early afternoon. Most of
them have black bodies, black wings and are usually a hook size 16 or smaller.
As with all stoneflies, the nymph is by far the most important stage of the
“Snow Fly” or "Winter Stoneflies" whichever you prefer to call them. That is
because
they all hatch out of the water.
Just for those that may be interested, these are the official species of Capniidae
Family that are found in the
Great Smoky Mountains National Park listed by
genus and species:

Allocapnia aurora
Allocapnia frisoni  
Allocapnia fumosa
Allocapnia granulata  
Allocapnia recta
Allocapnia rickeri
Allocapnia stannardi
Paracapnia angulata

What you need to know is that there are several species of them and that they
all
are very similar in looks and behavior.

Nymphs:
The nymphs are clinger or sprawler nymphs depending on the species. They
are dark brown to black, less than a half inch long and have long tails. They live
as a nymph for just under a year. They are found in medium to fast flowing
currents.


Coming Up Next:
Presenting Winter Stonefly Imitations

Copyright 2008 James Marsh
Flyfishingdvd's Imitating Aquatic
Insects: Stoneflies  
will teach
you what you need to know about
stoneflies and how to imitate
their behavior.