Cannot tell you how many customers over the years have come in with the same story, "tons of caddis hatching, but no fish rising". To which I ask, did you actually see any caddis on the water, or were they in the air and flying upstream? Yes, flying upstream, didn't see any on the water.... Simple observation solves the question, but it wasn't fully explained until Tom Ames ("Hatch Guide for New England Streams") filled me in on this one. The pupa crawl out earlier in the day, and the ones we see flying upstream actually lay their eggs on the undersides of leaves near the stream, and when the leaves drop, the eggs get into the stream. Weird, huh? I was able to repay the favor to Tom for the info, because he said the pupa weren't worth imitating because they crawl out and weren't very available to the trout. I told him to try a #16 Brown Serendipity in a nymph rig in the morning/early afternoon time period and he would be pleasantly suprised. Only took me a couple years to figure what nymph pattern would work for that hatch. Never said I was fast, did I?