CADDIS

Picture courtesy of Gary Borger

Last Week we discussed Mayflies. We compared insects to members of the animal family. We said there are big Dogs (Great Danes) and little dogs (Chihuahuas). There are white dogs, brown dogs, black dogs etc. They are all dogs but they aren’t the same.

Mayflies! There are big Mayflies (Hexagenia) and little Mayflies “(tricos). There are white Mayflies, brown Mayflies, black Mayflies etc. They are all Mayflies but they’re not the same.

All dogs have the same life cycle. All Mayflies have the same life cycle.

Cats. There are big Cats (Lions) and little cats (Siamese). There are white cats, brown cats, black cats etc. They are all cats but they aren’t the same.

Cats have fur like a dog, two ears like a dog, four feet, a nose and the same life cycle. But they aren’t dogs they are cats. There is no such thing as a Cocker Spaniel kitten or a Persian puppy. There is no such thing as a Mayfly pupa or a Caddis nymph.

Caddis! There are big Caddis and little Caddis. There are white Caddis, brown Caddis, black Caddis etc. They are all Caddis flies but they’re not the same.

Caddis have wings like a Mayfly, they lay eggs, which develop into the aquatic version of the bug. The aquatic version changes to an adult, mates, deposits eggs and dies like a Mayfly, but it isn’t a Mayfly, it’s a caddis.

Caddis eggs develop into larva. Larvae are wormlike aquatic versions of the caddis. Some larva build cases out of sand and stone, some from wood and other aquatic vegetation, some spin webs, others are free living.

Larva grow the most in the weeks prior to emergence. About three weeks prior to emergence, they seal themselves inside of an immobile pupal chamber and transform to a pupa. At the end of the three weeks, the mature pupa (pharate adult) cuts its way out of the shuck and heads for the shore or the surface.

Some pharate adults crawl ashore, (at these times you’ll find fish feeding in very shallow water) others form an air bubble and use it for buoyancy, and they ascend rapidly, pop through the surface film, and take off. This can drive fish nuts! Many times when you see fish clear the water, they are chasing pharate adults. This is a time when wet fly fishing and dry fly fishing merge. You use a pupa pattern but add floatant! (I like a product called “Frogs Fanny”. It floats the fly like a cork and provides wonderful bubbles).

The adults go to the vegetation, (in England they call them sedges because they go to the “sedge” grass). They will feed for a week or so as their eggs mature. The adult’s will then head back to the water, deposit their eggs and die. When there is a preponderance of adult caddis on the surface, they are usually dying spent adults. (Fish them with a twitch).

Many folks come into my shop enthusiastically asking for Black Caddis patterns because they see black caddis flying over the water. The problem is these bugs are over the water, not on it. I don’t know how to consistently imitate airborne insects. Black Caddis crawl into the water to lay eggs. The point is being observant.