Mink might be a good call if such lives around there. The only critters I know of that go in for wholesale slaughter like that just for fun are humans and weasels, of which minks are a variety. Otters are also a fair bet, depending on whether most of the fish were actually eaten or not, rather than just killed for fun... and otters do look a lot like giant weasels, and they don't mind getting wet...
I've known of weasels to get into hen houses around here and absolutely slaughter a bunch of chickens, then just leave them laying dead without eating any of them.
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I've known of weasels to get into hen houses around here and absolutely slaughter a bunch of chickens, then just leave them laying dead without eating any of them.
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“Trouble rather the tiger in his lair than the sage among his books. For to you kingdoms and their armies are things mighty and enduring, but to him they are but toys of the moment, to be overturned with the flick of a finger.”
― Gordon R. Dickson, Tactics of Mistake
― Gordon R. Dickson, Tactics of Mistake