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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