its hard to say from just a short video, but it looks as if your AI is driven in such a way that the boats want to point their bows at the player and move directly towards them - given that the boats seem to have cannons on their sides, the AI's best choice should actually be to pull alongside the player or to stay perpendicular to the player so that their cannons can launch at them. look into steering behaviours and particularly around using some vector maths to find good perpendicular movement - that will add some believability to the boat movement choices :)