or (

rain Rain is a form of precipitation where water drop (liquid), droplets that have condensation, condensed from Water vapor#In Earth's atmosphere, atmospheric water vapor fall under gravity. Rain is a major component of the water cycle and is res ...

trout Trout (: trout) is a generic common name for numerous species of carnivorous freshwater ray-finned fishes belonging to the genera '' Oncorhynchus'', ''Salmo'' and ''Salvelinus'', all of which are members of the subfamily Salmoninae in the ...

) is a giant whale- or fish-like creature from Ainu

folklore Folklore is the body of expressive culture shared by a particular group of people, culture or subculture. This includes oral traditions such as Narrative, tales, myths, legends, proverbs, Poetry, poems, jokes, and other oral traditions. This also ...

. Some of the largest ''amemasu'' are said to live in

Lake Mashū ( Ainu: Kamuy-to) is an endorheic crater lake formed in the caldera of a potentially active volcano. It is located in Akan Mashu National Park on the island of Hokkaido, Japan. It has been called the clearest lake in the world. Hydrology L ...

and

Lake Shikotsu is a caldera lake in Chitose, Hokkaidō, Japan. It is a part of the Shikotsu-Toya National Park. Geography Lake Shikotsu is located in the south-west part of Hokkaidō. It has an average depth of and a maximum depth of , making it the sec ...

Hokkaidō is the second-largest island of Japan and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by railway via the Seikan Tunnel. The ...

, with smaller ones inhabiting lakes throughout northern areas of

Honshu , historically known as , is the largest of the four main islands of Japan. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the list of islands by area, seventh-largest island in the world, and the list of islands by ...

. The ''amemasu'' are known for capsizing

boats A boat is a watercraft of a large range of types and sizes, but generally smaller than a ship, which is distinguished by its larger size or capacity, its shape, or its ability to carry boats. Small boats are typically used on inland waterways s ...

, creating earthquakes, and causing other natural disasters.

Appearance

An ''amemasu'' is able to take on a human appearance, usually of a beautiful woman, in order to lure young men to their deaths. The skin of an ''amemasu'' is said to be cold and clammy, much like fish skin, which is how they can be identified when they are in human form.

Legends

The inhabitants of

Hokkaido is the list of islands of Japan by area, second-largest island of Japan and comprises the largest and northernmost prefectures of Japan, prefecture, making up its own list of regions of Japan, region. The Tsugaru Strait separates Hokkaidō fr ...

believed that large ''amemasu'' held up the Earth. Sometimes, the fish would get tired and this could cause earthquakes, similar to the

Namazu In Japanese mythology, the or is a giant underground catfish who causes earthquakes. The creature lives under the islands of Japan and is guarded by the god Takemikazuchi enshrined at Kashima, who restrains the catfish with a stone. When t ...

. In

Akita Prefecture is a Prefectures of Japan, prefecture of Japan located in the Tōhoku region of Honshu.Nussbaum, Louis-Frédéric. (2005). "Provinces and prefectures" in ; "Tōhoku" in . Its population is estimated 915,691 as of 1 August 2023 and its geographi ...

, there is a place called . Legend says that the ''amemasu'' was so powerful, that it was able to kill a hawk, even though it died in the end. There is an island in the middle of

Lake Kussharo is a caldera lake in Akan National Park, eastern Hokkaidō, Japan. As with many geographic names in Hokkaidō, the name derives from the Ainu language. It is the largest caldera lake in Japan in terms of surface area, and the sixth largest l ...

in Hokkaido. The lake is said to be home to a large ''amemasu'', whose head resembled a rock and whose tail stretched to the

Kushiro River is a river in Hokkaidō, Japan. It is in length and has a drainage area of . The Kushiro originates from Lake Kussharo and flows south across the Kushiro Plain. The river is joined by two tributaries, the Kuchoro River () and the Setsuri Ri ...

. An Ainu hero, Otashitonkuru, took a harpoon, determined to poke out the eyes of the ''amemasu''. However, the fish started fighting back. Desperate to hold on to the harpoon, Otashitonkuru held on to a rock and the struggling ''amemasu'' pulled so hard that the rock became the island in the middle of the lake. In one tale, the ''amemasu'' swallows a deer that has come down to the lake to drink, but the deer's antler tears open the great fish's belly and kills it. The ''amemasu'' enormous corpse then blocks up the lake and puts it in danger of flooding. A god in the form of a bird warns the people in villages nearby. The villagers upstream escape to higher ground, but the people downstream, not believing the bird, find the ''amemasu'' body and drag it out of the lake, after which the water comes rushing out with such force that everything downriver is washed away. That area is now the flat Konsengen'ya plain.

Other Uses

''Amemasu'' is also a name given to the white-spotted char, ''

Salvelinus leucomaenis ''Salvelinus leucomaenis'', the whitespotted char, is an East Asian trout in the genus ''Salvelinus'', called ''iwana'' in Japanese and ''kundzha'' (кунджа) in Russian. Both landlocked and ocean-run forms occur. The landlocked form typical ...

''.

References

Ainu legendary creatures Monsters Mythological aquatic creatures {{Japan-myth-stub ja:アメマス#伝承