【Ayu (Sweetfish)】

Ayu

Classification: Order Osmeriformes / Family Plecoglossidae / Genus Plecoglossus

Size: Body length approx. 10cm-30cm

Habitat: Throughout Japan south of Hokkaido, and the southern Korean Peninsula.

Ayu is a representative clear-stream fish in Japan and has been cherished since ancient times. Its body color is slightly bluish olive on the back, turning silvery white from the sides to the belly. There are one to two bright yellow spots near the pectoral fin, called "oi-boshi" (chasing stars), which become more vivid when the fish establishes its territory. Ayu are highly territorial, butting intruders head-on into their bellies to drive them away. This behavior is utilized in a fishing method called "ayu no tomotsuri" (decoy fishing for ayu).