|.............................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 7
The Spotted Sedge (Hydropsyche species) are probably the most important
caddisflies on the Madison River, at least one of two that are. It hatches in huge
quantities and the trout eat them in three stages of their life - the larva, pupa
and adult stages. There are more than one species of these caddisflies that are
all very much alike in appearance and behavior.
These are net-spinning caddisflies that are not really ever well protected from
the trout. The larvae build tiny nets to trap their food and are subject to being
eaten by trout in this stage that represents most all of its life. The short time the
caddisfly (approximately three weeks) is in it pupa stage, it is completely
helpless and eaten by the trout will ease. The adult females swarm the water to
deposit their eggs in the evenings and are eaten by the trout on the surface at
that time of their short adult life.
During the very short fly-fishing season in Yellowstone National Park, it is rarely
necessary to fish a larva or nymph imitation of any aquatic insect. You can catch
trout on dry flies most any day. However, if you are ever having problems doing
so, just tie on an imitation of the Spotted Sedge larvae and you will not be
disappointed. This is our own "Perfect Fly" imitation:
We normally place a non-toxic weight about eight inches above the larva fly and
fish it in both the riffles and slower moving areas of the smooth water sections.
These little caddisfly larvae are just about everywhere there is water in the
Madison River, not only in the park but throughout its entire length. These flies
work anytime of the season from opening day until the hatches have ended.
The pupa imitation should be fished down and across and allowed to rise from
near the bottom to the surface during a Spotted Sedge hatch. It is extremely
effective at that time. The adult female caddisflies will start depositing their eggs
late in the afternoon and continue on into the evenings. The best time to fish
this stage of the hatch is very late in the day after the sun has set until as late
as 10:00 PM and probably even later if you care to keep fishing.
Copyright 2009 James Marsh
Perfect Fly Spotted Sedge Larva
Perfect Fly Spotted Sedge Pupa