An oarfish, a large, incredibly long member of the order lampriformes known for dwelling in the twilight zone, has recently washed up near Baja California Sur, Mexico. Japanese folklore labels the oarfish the “doomsday fish,” leading many people to believe its appearance signifies an upcoming natural disaster.
In Japanese mythology, the oarfish is called “ryugu no tsukai,” otherwise known as the “sea god’s palace messenger.” This myth can be traced back to the seventeenth century. The whole “harbinger of disaster” belief surrounding the oarfish was further supported by the earthquakes that devastated Japan in 2011.
However, the science behind why an oarfish might pop up right before a 9.0 earthquake suggests that they are not really sea god messengers. Since oarfish live so deep underwater, about a thousand meters below the surface, they live close to fault lines. When seismic activity occurs, it most likely disturbs the fish who are just a bit more sensitive to the waves underwater. Due to this, they are more inclined to travel to the surface, which is why they show up on beach shores.
So, while the oarfish may be deemed the “doomsday fish,” there is no real science that links it to such folklore.