Distribution of White Shark in Japanese Waters

Abstract

The white shark was thought to be rare in Japanese waters except Okinawa, but the author doubted its rarity because of its coastal and temperate habitat and eurythermal nature. Therefore, records of large sharks were collected since 1992 and closely examined. Nineteen of sharks were the white shark Carcharodon carcharias, and such a high incidence in catches or sightings in only 18 months is surprising, because previous published records indicate for fewer numbers. Since many of the larger sharks are not landed because of their low commercial value, and since smaller specimens were not included in this survey, the white shark is not a rare species in Japan. The white shark is known to exist in waters of 7 to 27°C (mainly 15 to 22°C), and its eurythermal nature suggests that the species can remain all year round in the southern and middle parts of Japan. However, the white shark seems to be a seasonal visitor to the waters of northern Honshu and Hokkaido.