While fishing a local lake Friday with my trusty woolly Bugger and picking up a few fish I noticed a lot, I mean a lot of "Damsel" flies around me. On my boat, rod, arm, fly line. So I looked in my fly box and picked out what I thought would match a Damsel nymph. Full sinking line, 5-8' of water right next to the Lilly pads. WHAM. They just started nailing that fly.(trolling slow). I released 6-7, 14"-17" trout. Plus another 5-6 12" fish. I'm including a couple of PIC of what was in 2 of the bigger fish's stomach. They didn't just strike this fly they attacked it. ( 2 fish got gill hooked. In cleaning them I found these).Can anyone tell me why the was a rock in one fish's stomach?