.......................  ....................  ...Fly Fishing Yellowstone National Park
05/15/12

New KISS Bug Series - Part 19

The Little Black Caddisflies
Lavae









The Little Black Caddis, or American Grannom larvae are cased caddisflies that form square cases made
of small sticks or plant material. You will find these chimney cases dangling from rocks and anything else
they can attach too. The larvae use silk they produce to attach the cases to objects in the water. The
unique shape and structure of the larvae makes them easy to identify. In fact, the neatness, accuracy and
overall construction abilities of these simple animals is amazing and very impressive as far as I'm
concerned.

Trout will probably eat the larvae, wooden case and all, but not to the extent we think the larvae deserve a
fly pattern. I am only mentioning this stage of life and showing you a picture of the chimney cases so that
you will be able to recognise and identify the particular caddisfly called the Little Black Caddis or
sometimes, the American Grannom. The cases make that very easy.

There are several fly patterns that have been developed to imitate these cases and larvae, so apparently
others disagree with us as to their effectiveness. You should certainly try them if you tend to agree with
those that have developed fly patterns for them. I'm sure the larvae, case and all, are eaten by trout to
some extent. Like many other things, fishing success depends on the odds you face. The higher the odds
of things involved with something working - techniques, methods, flies, etc., the higher your odds of
success. We just don't think fishing an imitation of the Little Black Caddis larvae cases provide very high
odds of success.
Copyright 2012 James Marsh
Little Black Caddis:
Species:                             
Type:                                  
Availability to trout:             
Hook Size:                          
Numbers:                            
Distribution:                        
Type of water:                    
Emergence time:                
Duration of hatch period:

Brachycentrus occidentalis, B. americanus
Cassed Caddis (Short-horned Caddis)
Excellent
16/18
Heavy
Widespread
Moderate to slow - smooth and broken surface
Afternoons
Medium