|.............................Fly Fishing Yellowstone National Park
I am calling this series Yellowstone Journals and Additional Information. It is a collection of a
rambling mixture of experiences on the streams with some notes, tips and additional
information thrown in. Some of this comes from my video tape logs (record of video shot)
and notes made on my daily note books.
Fly Fishing the Upper Madison - Part 11
The Little Plain Brown Caddisfly (Lepidostoma pluviale) is another one that
hatches during the time period the Madison River in Yellowstone National Park
may be too warm for good fishing. Again, during the last ten years we have only
found two summers where the water in the river did not get into the low
seventies. One of those two were marginal. This caddis is especially plentiful in
the Yellowstone River as well as many other streams in the park.
The Little Brown hatches from about mid-July until mid-August in large quantities
in the Madison River. Since the water condition could be fine during the
summer, I am going ahead and mentioning this one. The best part about it is
that is emerges mid-stream as opposed to crawling out of the water. By the way,
when I say mid-stream, I am referring to anywhere in the river, not necessarily
out in the middle of the river. That is just a term used to separate it from those
that emerge a different way.
Little Brown larvae have circular cases made of sand. The pupae of the Little
Brown Caddisfly (also called Little Brown Sedge) swim to the surface to hatch.
They change into adults on the surface and fly away to nearby stream side
vegetation very quickly. The females will return on a later day to deposit their
eggs. They also do this on the surface of the water and actually drift the surface
a good ways before flying away or dieing. This means the Little Brown Sedge
provides a good opportunity for you to catch trout on both pupa and adult
imitations. There is only one problem with this. They hatch very late in the day
starting after the sun has set and on into the night. They deposit their eggs
during the same time period. I say this is a problem but it is much better for them
to hatch when the water has cooled some. The air temperatures along the
Madison River can and ofter does drop down to about forty degrees at night on
some of the hottest days of the summer. That brings the water temperature
down some and increases the activity of the trout. As I have mentioned before,
that may still only provide smaller trout because many of the larger ones, if not
all of them, move to Hebgen Lake during the bad water years.
These are small caddisflies. They range from a hook size 18 to 20 depending
on the sex. Our "Perfect Fly" imitations come in a hook size 18. These
caddisflies hatch mostly in the smooth water sections of the Madison River. We
usually start with the pupa imitation first about the time the sun sets and
continue to fish it for an hour or so. We will swap to the adult pattern depending
on the results of the pupa fly.
There will be a lot of other caddisflies hatching at the same time. The Long-horn
caddis, Green Sedges (in the fast water sections), Spotted Sedges and Little
Black Short-horned Sedge may also be hatching. When the Little Browns start
hatching they usually outdo the other species in terms of quantities of them on
the water for a week or two.
Copyright 2009 James Marsh
"Perfect Fly" Little Brown Sedge Pupa