Strangest thing I ever saw with a rainbow was a few years back. I took my Grandson fishing on a local lake. Since he did not fly fish, we were using bait. He caught a couple of nice fish and wanted to take them home to eat. I told him that I would show him how to clean the fish and how to cook them. It was a golden moment for me. Anyway, when we got home and he opened the one fatter fish, it's gut was filled with a rubber toy dragon that had expanded with water. I doubt that the fish could have ingested a morsel of food and was probably starved for something to eat. I suppose a child had been playing near the water and the toy ended up in the drink, fish ate it, end of story.