Originally Posted by attila
Today while on the stream I noticed what must be millions of tiny little cocoons stuck to the rocks. These were made of tiny pepples. I'm guessing some sort of caddis ?
Sounds like a type of Glossosoma
species - and yes, they are caddisfly larva. They make little "turtle shells" out of pebbles and crawl over rocks skimming the algae off.
The actual color of the larva themselves (inside the casing) is pink (I believe) and they do frequently end up in the drift as they outgrow their homemade shells.