I'd like to say I'd report him but I don't know...
I'd suggest that you have a conversation with a game warden and explain all of it. That you work with him etc. The warden is going to do surveillance, watch him catching and keeping sun fish and then later bass fishing. Maybe someone reported him, maybe someone didn't. I might also suggest giving your HR person at work a heads up.
I LOL when I went back and read that he follows the 25 possession limit.