I noticed tonight that one of my four ducklings has a decent size lump on the right side of his neck right at the base. They did just have a good snack of banana and lettuce, so maybe it's the crop? But only one of them has it. I'm worried it's a cyst or something. He didn't seem too fond of me touching it, but didn't scream or seem too in pain. I can try to post pictures tomorrow. Any help is much appreciated!!