Hunting is when you ACTIVELY engage the animal that you intend to kill, whether by stalking, scouting, etc... to locate and kill.
I would think what he does is the same, accept he needs a boat, to stalk,scout etc....to locate the whale, and his hunting area is an entire bay or ocean, the boat is just the means of the stalk, just like walking is to land hunting.
I wouldnt think that he would just sit in the boat,waiting for something to swim by.
(not disagreeing with you, just sayin that im sure its not as "easy" as say sitting in a deer stand waiting for something to walk by. )
Greens, id be curious, how exactly is it done?