Tradition / Region: Japanese Mythology
Alternative names: Kawakuma
Category: Bear
The Myth
The Kawaguma, meaning “river bear,” is an aquatic yōkai said to inhabit the deep rivers of northern Japan, particularly the Omono River in Akita Prefecture and the Shinano River in Niigata Prefecture. Covered in black hair and rarely seen by humans, it spends most of its life hidden beneath the water.
Little is known about the Kawaguma’s habits because it remains at the bottom of deep rivers. It is sometimes curious enough to approach boats, clinging to their sides or stealing objects and dragging them back to its underwater lair. It is also blamed for digging into riverbanks, causing them to collapse and bringing about floods.
One famous legend tells of a lord who was hunting from a boat on the Omono River when a black, hairy hand suddenly reached up from the depths and snatched away his rifle. A skilled diver later recovered the weapon from the deepest part of the river, and it thereafter became known as the “Kawaguma gun,” remaining a treasured possession of the Satake clan.
Another tale recounts how a ferryman had just tied up his boat for the night when he heard a splash behind him. Looking back, he saw a pair of black, hairy hands gripping the side of the boat. Startled, he struck at them with a large knife. The following morning, a severed hand was found inside the boat. It resembled the paw of a cat but was covered in black fur, and everyone who saw it declared that it belonged to a Kawaguma.
Sources
Foster, M. D. (n.d.). Kawaguma. In Yokai.com: The Illustrated Database of Japanese Folklore. Retrieved June 29, 2026, from https://yokai.com/kawaguma/.