Tradition / Region: Japanese Mythology
Alternative names: Water Beast of Mizushima
Category: Bear
The Myth
The Mizuguma, or Water Bear, is a mysterious black beast said to have lived in the depths beneath Mount Hakusan. It was believed to be responsible for the devastating floods that repeatedly struck the Tedori River during the 18th century.
During one of these floods, people noticed a huge black object protruding from the river. It resembled neither stone, wood, nor the body of a dead animal. Covered in black, leather-like skin, it had no visible eyes, nose, or head, only several branch-like limbs. Hoes and bamboo poles could not pierce its hide.
When a coconut floated downstream, the creature suddenly extended one of its limbs, seized the fruit, pressed it against its mouthless body, and drained the oil from within before letting the empty shell drift away. Realizing it was alive, the villagers tried to burn it with flaming straw. The fire finally split its hide, drawing black blood.
The wounded beast responded with a tremendous roar. Towering waves crashed onto the riverbanks, embankments burst apart, and floodwaters surged across the countryside. Wherever the creature rolled, deep pools formed, and the flooding continued to devastate the surrounding villages.
Unable to defeat it, the people prayed daily by reciting the Kannon Sutra for one hundred days. One night, a faint light appeared, and the black creature was seen swimming upstream toward the mountains. After its departure, the floodwaters receded, the river returned to normal, and the Water Bear was never seen again. It was thereafter believed to dwell once more in the deep abyss beneath Mount Hakusan.
Sources
TYZ. (n.d.). 水熊 (Mizuguma). In 新版TYZ 妖怪図鑑. Retrieved June 29, 2026, from https://tyz-yokai.blog.jp/archives/1071303462.html