Basics of Fly Fishing: Trout Food Series - Top Questions on Adult

1. Why do anglers usually have less success fishing imitations of adult
caddisflies than mayflies?
When anglers start seeing the air and bushes full of caddisflies, they tend to think
that is what they should be trying to imitate. It is possible that is correct, but most of
the time those caddisflies don't get on the water. They are either breeding or
waiting for the right time to deposit their eggs. When eager anglers start fishing
their dry fly imitations of the adult, they have little success because the trout are not
used to seeing them on the water.

2. When is the best time to imitate an adult caddisfly?
There are two important times with some groups of species (genera) of caddisflies
and only one with other groups of species (genera). Those that hatch in the water
(see yesterday's article) are eaten by trout as adults before they can depart the
water from the hatch. Those that hatch out of the water are not eaten by trout in the
adult stage of life during the hatch. The other time, is when the females deposit
their eggs.

3. How do the caddisflies deposit their eggs?
This is done three basic different ways. One way that is most familiar with most
anglers is for them to deposit them on the surface of the water. This is usually done
by them actually landing on the surface or by skittering across the surface and
knocking them off. The second way is for them to dive into the water and paste their
eggs on objects such as rocks and plant stems. The third way is for them to crawl
down the banks, rocks and boulders into the water and then paste their eggs on

4. Which method do you imitate with a fly?
The first two above or those that deposit them on the surface or those that dive and
paste them on objects in the water. Those that crawl down objects can be imitated
with a fly (a fly in the water, not crawling down objects) to some extent, but we have
found that it's not very productive to do so.

5. Where do caddisflies die?
Some of the females die on or in the water after depositing their eggs. A certain
percentage get back to the banks and die on land. Most of the males die on land.

Why do anglers usually have far more dry caddisfly imitations (adult
imitations) than imitations of the larvae or pupae?
They falsely assume that is the fly to fish when they start seeing caddisflies around
the water, when it usually isn't. Trout eat far more caddisfly larvae and pupae than
they do adults. The adults are far more difficult for them to catch to eat than the
larvae or pupae. My guess would be that adult caddisflies represent less than 1% of
the total number of caddisflies eaten by trout. Another reason for the dry fly
domination, is the fact that it's more fun to fish a dry fly.

Copyright 2009 James Marsh