I recently returned from 3 days in Idaho fishing NF Clearwater (fishing was good). Each time I go, I am amazed how how many large cased caddis are clinging to the rocks; they are everywhere and the same holds true for all the streams in north central Idaho. However, on trips later in the fall like September and October, the caddis are completely gone from the shallow rocks where they are located in the summer. I assume they migrate when they hatch but where do they go and why don't you see them? You can find the egg-laying adults in the evenings as they return to the water and there are some fish keying in on the adults. However, at what point during the life stage do trout really key in on the nymphs during their emergence? I have seen cased caddis patterns in fly shops. Are there times when trout eat case, worm and all?