Floating apparition on a bright overcast sea
Ukimono
An island that should not exist floats under a pale sky. The prow turns toward it, and the island dissolves. The sea has as many lies as islands.
Overview
Ukimono is a sea apparition from Awashima in Niigata. Around May or June, on bright overcast days, something like a giant fish or landmass appears on the sea and disappears when approached.
Encounter
A boat moves through the waters around Awashima when an island-like shape appears where none should be. As the boat draws near, the thing melts from sight.
Lore
It is recorded in works such as the Comprehensive Japanese Folk Vocabulary. Explanations include fish schools, flocks of birds, or an unknown giant fish, but its disappearance prevents certainty.
Traits
It floats like a giant fish or island and may move over the sea. It is tied to early summer weather and a fairly stable location, and no direct attack is recorded.
Several ri offshore, something like a great fish or small hill sometimes appears and floats.
Miyagi-ken Shi, Minzoku 3