We get nibbled all the time here in KY Lake. Just panfish, as said above. Panfish, bluegill, sunfish, perch, brim, whatever you want to call them. They are all close to the same if I'm not mistaken.
I took my first 2 dives of my open water certification yesterday, and we were all getting bit by the little bluegill/brim. The seem to like ears. The quarry we went to was no fishing allowed, so the fish were very friendly. Even drew blood on a couple people with their nibbles. Little creepy at first. I watched one swim up slowly and bite a thread hanging off of my wetsuit, haha. They were very small though, few inches long at the most.