Oshima Strait Marine Life

The 20-kilometer strait between Amami-Oshima and Kakeroma islands cuts 50 to 70 meters deep beyond the coral reef slope, creating a rich channel for marine life. Sea turtles and dolphins move through regularly, and humpback whales migrate here in winter. The coral-fringed ria coastline, formed where the sea flooded ancient river valleys, has become popular with scuba divers and snorkelers who explore the reef habitats. Islanders farm bluefin tuna and cultivate pearls in these same waters, and have fished here for bonito for centuries. The narrow passage's sheltered waters have historically served as a typhoon refuge for vessels caught in the open sea.