Trout eat a lot of stupid stuff, put it this way they are definatly not the smartest fish around. I have found a lot of bass plastics in their stomachs, about out of every 7 rainbow trout Ive kept at least one or two have bass plastics in them. Ive also thought the have been eating rocks when their stomach felt like there was a ton of pebbles inside but when I opened them up they were all just a bunch of snails.