The funayūrei (船幽霊 or 舟幽霊, lit. "boat spirit") are ghosts (yūrei) turned vengeful spirits (onryō) at sea.
Passed down in the folklore of various parts of Japan, they appear frequently in ghost stories and miscellaneous writings from the Edo period as well as in modern folk lore.
In Yamaguchi and Sage prefectures, they are called ayakashi.
The funayūrei are ghosts supposedly using hishaku (ladles) to fill boats with water and sink them. They are supposed to be the remains of people who have perished in shipwrecks and try to entice humans to join them.
According to the legends, there are different methods that can be used to protect from the evil they inflict, such as throwing onigiri into the sea or preparing bottomless hishaku.
They are also called mōjabune (亡者船), bōko, or ayakashi depending on the place. The umibōzu, other strange phenomena at sea, are sometimes considered to be a type of funayūrei rather than a type of yōkai.
Their appearance as described in legends varies widely depending on location. There are stories about ghosts appearing over water, ships that are themselves ghosts (ghost ships), ghosts appearing on occupied ships, or any combination of the above. They are described appearing as umibōzu or kaika.
There are many legends of funayūrei at sea but they have also been described as appearing in rivers, lakes, and swamps in inland areas.
In Kōchi Prefecture, kechibi, a type of onibi, is also sometimes considered to be a type of funayūrei.
They often appear on rainy days as well as on new or full moon nights and on stormy and foggy nights. When it appears in the form of a boat, the funayūrei itself shines so that it is possible to make out its details even at night.
In addition, acting on the sixteenth day of Bon, the dead try to approach the side of the ship and sink it.
On the other hand, on a very foggy evening, while trying to drive the ship, a cliff or a boat without a pulley appears and the fright caused and the attempt to avoid them results in capsizing or running aground on a reef, it is easy for them to simply push forward and make the ship disappear naturally.
Aside from attempting to sink ships, in the town of Ōtsuki of Hata District in Kōchi Prefecture, they are said to cause the boat's compass to malfunction and in Toyoma Prefecture, fishing boats traveling to Hokkaidō turn into funayūrei, causing the crew to hang themselves.
In Ehime Prefecture, when one encounters a funayūrei, if one tries to avoid it by changing the boat's course, the boat runs aground.
Also, in the past, in order to avoid a shipwreck on a bad weather day, people would light a bonfire on land but a funayūrei would light a fire in the open sea and mislead the boatmen, and by approaching the fire, one could be swallowed by the sea and drown.
There are also various legends about how to hunt a funayūrei depending on the region and in Miyagi Prefecture, when a funayūrei appears, it disappears if one stops the boat and stares at the funayūrei for a while.
It is also said that it is good to stir the water with a stick. There are also various theories that it is good to throw things into the sea and in Kōzu-shima it is flowers or incense, dango, washed rice and water, in Kōchi prefecture it is ashes and 49 rice cakes, in Otsuki, Kōchi prefecture it is summer beans, in Nagasaki prefecture it is braided mats, ashes and burnt firewood.
Also in Kōchi Prefecture, it is said that it is possible to ward off funayūrei by saying "I am Dozaemon" (わしは土左衛門だ) and claim to be one of the funayūrei. In Ehime Prefecture, funayūrei can be dispersed by lighting a match and throwing it away.
In the Edo period collection of Ehon Hyaku monogatari fantasy stories, the funayūrei that appear on the western sea are the souls of the deceased Taira clan.
It is known that the Taira clan disappeared after the battle of Dan-no-ura, but in the open sea between Dan-no-Ura and Mekari in the Kanmon Strait (Hayamoto, 早鞆), a funayūrei wearing a helmet and armor appears, says, "Give me a seal," and clings to the boat.
Using a hishaku, he pours water on the boat so when one has to cross this sea, one has to do so by preparing a boat with the bottom open and thus dismiss the funayūrei.
Once, a Buddhist priest taken with a feeling of pity for the spirit, gave it a Buddhist service, causing it to disappear.
Genrin Yamaoka, an Edo period intellectual, wrote about funayūrei appearing as balls of fire or ghosts at sea.
Referring to Zhu Xi and the Cheng-Zhu school, he mentions several examples of souls of the dead who died with resentment and remained even after their vengeance was carried out and concludes,
"Even when something is seen by ten people, reasoning, you can also see it sometimes in the ancient Chinese books." (かやうの事つねに十人なみにあることには待らねども、たまたまはある道理にして、もろこしの書にもおりおり見え待る)
Although it is not possible to get a smoke catch with his hands, by accumulating and staining one's hand it is possible to hold some in one's hands.
Spirit (気, ki) is the beginning of one's nature and when spirit stagnates, those who create form and produce voice are called yūrei. In the first place, the stagnant spirits of ghosts desire to fall and disappear.
In 1954, after the Tōya Maru incident, the largest maritime accident after the war, it was discovered on the ferry boats that went into commission after the accident that they bore a strange scar on their propellers, providing an example from where rumors began to spread about how the victims of the accident turned into funayūrei and dug into the propellers with their claws.
This funayūrei appears at sea and on land, and in Nanaehama, Hokkaidō, a rumor has it that at midnight, a fully soaked woman appears riding a cab and disappears once she reaches her destination and is rumored to be the ghost of the Tōya Maru.
Also, at Aomori Station, staff members sleeping in the night guard room wake up to the sound of a knock on the window and see the woman's hand completely wet on the other side.
They are seized with the news that "victims of the Tōya Maru are asking for help," and the next morning they find a note written on the pane of that window.
In 1969, on the sea of Kanagawa Prefecture, a white human figure is observed and a voice is heard saying, "Please give me a hishaku," and it is said that the shipwrecked members of the university yacht club want to bail out of the water.
According to folklorist Hideo Hanabe, funayūrei appear during evenings of wind, rain, and thick fog, and also frequently when the weather suddenly deteriorates, and since accidents occur more easily at these times, these circumstances add a sense of reality.
Since they also give a sense of strangeness and uneasiness, some of these strange incidents are inserted into a frame of legend, so that ghosts and illusions are spoken of as reality.
The fact that they often appear during Bon duplicates that of the shōrōbune.
However, at root, as not deified, there is also a belief in the spirits of those who died at sea and float around and transform into funayūrei, and in Bon, on New Year's Eve and other set days, it is forbidden to fish or go to sea, forbidden to approach the sea, and forbidden to break these taboos.
The funayūrei pass for possessing ships and preventing them from moving20 but in modern times they have received a scientific explanation that associates them with an internal wave phenomenon.
In the region of the ocean that is at the mouths of large rivers, for example, there are areas of low salinity water and since the low salinity water is relatively light, it stagnates at sea level but the water on both sides moves little and forms a boundary.
Around this boundary, if the boat has a propeller, even if it turns, the energy only stirs the water at the boundary and is spent entirely on creating internal waves that prevent the boat from moving.
In the polar regions, the ice will melt and float in the middle of the sea, creating the same result that the polar explorer Nansen also observed.
Thus, there is a hypothesis that internal waves accompanied by changes in salt content, water temperature, and hydraulic pressure impede the ship's progress.
Coast of Fukushima prefecture. It is about people on ships who say "Lend me an inada" (hishaku). An inada is a hishaku used on ships, if you don't open a hole in it before giving it to him, he suddenly fills the ship with water and makes it sink.
Kowaura, Minamiise, Mie prefecture. During storms he can say "Lend me a hishaku" to boats too slow to run away and sinks them. By lending a hishaku with a hole in it, it is possible to flee and return safely.
Tsumamura, Oki district in Shimane prefecture (now Okinoshima). Here, what might appear to be noctiluca in the lake is supposed to be a crystallization of salt, but if you stare at it, the thing that solidifies into a spherical form while shining is Murasa. If the boat passes over it, it will suddenly sink.
Furthermore, there are cases where at night the sea suddenly glows, but this is because it is possessed by Murasa, and it is said that it is effective to tie a sword or a knife to the end of a pole and shake the sea repeatedly.
Aishima, Abu District, Yamaguchi Prefecture (now Hagi). By rolling up a white sail and running it forward, the funayūrei would also run along. By scattering ash and making a sound, it would disperse.
Hirado, Nagasaki Prefecture and Goshoura-jima, Kumamoto Prefecture, among other places in Kyūshū.
It is said that when a boat is possessed its movement is hindered and in Hirado, a sailboat comes to chase it, even if there is no wind. On the west coast of Kyūshū, the funayūrei appears as an illusion of a boat or an island.
In order to avoid this, in Hirado one must throw ashes and in Goshourajima one must say "I am lowering the anchor" (錨を入れるぞ) while throwing a stone and then drop the anchor. The funayūrei disappear if someone smokes tobacco.
They are also known to appear by saying, "Give me an akadori (淦 取 り)," a bucket for removing water that collects on the bottom of a ship), and they sink a ship if they are not given an akadori with the bottom open.
Onga District in Fukuoka Prefecture and in the same prefecture Kanezaki, Munakata. On moonlit evenings around the Bon period, they appear as sailing ships at sea. It is said that a kaika appears and people's voices can be heard.
Kaijō District, Chōshi, Chiba Prefecture (nowadays Asahi). On deep foggy days and stormy days, a funayūrei appears to fishing boats and it is said that the spirit of someone who perished in a shipwreck tries to increase the number of his fellows.
A voice approaches the boat saying "Mouren, Yassa, Mouren, Yassa, hand me an inaga" (モウレン、ヤッサ、モウレン、ヤッサ、いなが貸せえ ) and suddenly a hand comes from the sea, saying:
"Give me a hishaku" but as it sinks the boat if you give it a hishaku, it is said that you must give a hishaku with its bottom open. Mouren means "ghost", inaga means a hishaku and yassa are the shouts of encouragement used when rowing a boat.
In the work of yōkai mangaka Shigeru Mizuki, this is written as "Mourei Yassan" (猛霊八惨) and in Sakaiminato in Tottori Prefecture, Mizuki's birthplace, a festival was established to appease this Mourei Yassan.
Appearing in Fukuoka Prefecture among other places, they are considered a species of funayūrei.
In the legends of Kosode, Ube town of Kunohe district in Iwate prefecture, (nowadays Kuji), it is a yōkai that frequently appears with black ships and they make an impossible request:
"Give me a paddle in stormy weather" (時化(shike)の時などに櫂(kai)をよこせ) but there would be no point in answering or lending them a paddle.
According to the Keirin manroku (桂林漫録) (written during the twelfth year of the Kansei era), there are writings such as "The ghosts of the drowned become ghosts that capsize ships" (覆溺(fukuteki)して死せる者の鬼(ghosts)を覆舟鬼ということ) and
"They are seen in writings relating to the yōkai of beyond beyond the seas" (海外怪妖記に見たりと) indicating that it has also been written in China about what is considered funayūrei by the Japanese.
In China there are legends about a phenomenon called Kikokutan no kai (鬼哭灘の怪) where discolored monsters try to capsize ships (they are close to umi-bōzu).