There's no "animal lovers only" screening for boat ownership, and the captains & owners of small boats are often very invested in them (emotionally and/or financially). Reasonable assumption: The shooting started a while ago, it's only scale-up and media coverage that are matters of time.
It is rare for boats to have guns, as transporting guns between countries is a very difficult affair.
Edit, found a source: https://euroweeklynews.com/2023/08/18/sailboat-crew-denounce...
If theyre breaching the surface, the amount of flesh you’d have to pierce to get a kill shot would be a lot. Maybe it would deter them but I think it’d just make them angry and would be a dumb idea.
That is, if you get the predator before it gets your object of value, the data point is lost.
We have always been at war with Oceania.
Very well put.
Though (as others have pointed out), common small firearms are not well-suited to this use case. Might you know about the legality of spearguns, or similar weapons?
I'd guess that small explosive charges - typically used for https://en.wikipedia.org/wiki/Blast_fishing - would be both "obvious", and easily available to those least inclined to lawful behavior. And it'd be easy enough to check whether their use would attract real naval or coast guard attention.