Perhaps an insanse necromancer has created a school of vampiric asian carp (or the layo equivalent of asian carp). Ships gone off course, found with only the withered husks of their exsanguinated crew.
No evidence is found, only the corpses of the crew and the sunbaked remains of a few fish that got caught on board.
Someone must stop these bloodsuckng fish and their dark master! Muahahahaha.
Perhaps an intrepid crew, led by an elite team of powerful druids and armed with the Holy Fishing creel of Toran is the only hope of Layonara.