Picture of the Seven Islands of Izu: Niijima Island: Picture of Turtle
Painted by Hasegawa Shinkichi 1846 (Kōka 3) Kondo Marine Memorial Foundation Collection Library 271

Since ancient times, turtles were hunted in the seven Izu Islands. The islanders possessed unique techniques for capturing the green sea turtles underwater. Green sea turtles are also known by the name "shōgakubō."