> somewhat less likely. Very well put. Though (as others have pointed out), common small firearms are not well-suited to this use case. Might you know about

> somewhat less likely. 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 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.