This is one of several captains of ships which I've boarded who tried to fight me with their bare hands. They ignore the musket and bayonet with which they're equipped, and which I take from their dead bodies. One captain did fight me with a weapon, but it wasn't the musket. Some captains have more than one melee weapon and that one had a sword as well as the musket, so he used the sword. I still took the musket from his dead body. Other types of enemies seem to use their muskets with bayonets, it's just ship captains who seem not to know what that thing is for.