It Went Swimmingly
I had a whole carp in my backpack. I was visiting my grandparents in the Czech Republic right before returning to spend Christmas with my parents in France. Carp is our traditional Christmas dinner in the Czech Republic, but it’s pretty hard to get in France, since French people don’t eat them.
So I figured that, hey, I might as well buy one and take it with me. The lady who checked my bag was not impressed, but she let me go through with my carp. I guess there’s no rules against taking an entire fish with you on a plane.