.......................  ....................  ...Fly Fishing Yellowstone National Park
05/16/12

New KISS Bug Series - Part 20

The Little Black Caddisflies
Pupae










The Little Black Caddis pupae swim to surface much like most mayflies do when emerging.  Tha's one thing
that makes this hatch important to anglers. They see the caddisflies hatching during daylight hours like the
mayflies they are use to seeing and have less problems imitating them than they do with many of the other
caddisfly species. It also clues anglers in on when the hatch is underway unlike many other caddisfly
species. Most of the time with many other species of caddisflies, anglers aren't even aware a hatch is
underway until it has ended.

These caddisflies don't usually hatch in shallow water or near the edge of a stream like many other aquatic
insects do. They usually hatch mid-stream and by that I mean anywhere out in the stream.

The Little Black Caddis hatch usually starts in the early afternoon and can last until late afternoon. Often
the hatch is still underway when the female adults begin to deposit their eggs on the surface. This usually
occurs later in the afternoon and can add activity to the point it becomes a feeding frenzy.  

I have read that the pupae swim to the surface using their middle legs aided by air bubbles. They hatch in
the surface skim by shedding their thin pupa skin and drying their wings. They then proceed to fly away to
the stream side bushes, trees or grass.

It's during the time that the pupae are accenting to the surface and changing into an adult fly that the trout
feed on them the most. The trout will just flash or swirl beneath the surface when they are taking the
pupae. Sometimes you can see the surface disturbance and sometimes you can't see any disturbance. It
depends on the particular type of water. Far more pupae are eaten by trout that newly hatched adults.
This is the stage of the hatch you want to imitate.

Pupae Presentation:
The pupae usually hatch in water that is relatively smooth even in streams that consist mostly of fast
moving pocket water. The will also emerge in the moderate sections of smooth flowing water. They do this
quite frequently in the Firehole River and sections of the Madison River. In pocket water, the Little Black
Caddisfly larvae seek the slower, smoother areas of the stream, such as the pockets behind rocks, to
emerge.

You should add a slight amount of weight to the tippet about six inches above the fly. This will help get it
down but don't overdo it to the point you have trouble getting the fly to come back to the surface at the end
of the drift. That can happen in the moderate section of water  if you use too much weight.

If you are fishing pocket water, then I would suggest you use an across stream presentation of the Perfect
Fly pupae imitation. Under these conditions, you can get much closer to the feeding trout fishing
upstream. In smooth flowing streams you may be better off using a down and across presentation. It can be
difficult to get very close to the feeding trout in smooth flowing areas of water.  

With either type of presentation, across stream or downstream, you want to imitate the pupa swimming to
the surface to hatch. You do that by simply stopping the rod near the end of the drift and allowing the fly to
rise back up to the surface. The current will bring the fly back to the surface for you.  
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