Originally posted by knighttemplar1960:

They will attack it if you are in it or were in it and got out. Jumping fish can also damage your boat if the boat is above the fish when it jumps though they don't specifically attack the boat.

This is also false. They will not attack the boat "if you were in it then jump out." I just tested it, I welcome you to test as well. I have my doubts about the fish, but have no reliable way of confirming, and I think you may have gotten mixed up with wave/lag damage to the boat (usually a flat 10 damage), which has nothing to do with fish.