WEBRyukyuan, Japanese. Tokunoshima ( Japanese: 徳之島, Tokunoshima: トゥクヌシマ, Tukunushima), also known in English as Tokuno Island, is an island in the Amami archipelago of the southern Satsunan Islands of Kagoshima Prefecture, Japan. [1] The island, 247.77 km 2 (95.66 sq mi) in area, has a population of approximately 27,000.