AS blackcatter pointed out, while the little dear is peering into the barrel, it keeps him out of muschief. (It hs to be a "him" hasn't it?)
Has anyone ever tried shooting fish in a barrel? I'd imagine it could be quite entertaining for spectators, what with the bullets going through the side and the water spouting out. I don't imagine the fish would get hit very often, what with refraction and that. And anyway it's pretty dark inside the average barrel.