Okinotori

Lore & Background

The atoll may have been first sighted by Spanish sailor Bernardo de la Torre in 1543, with the first undisputed sighting by Miguel López de Legazpi in 1565, who named it Parece Vela ('looks like a sail'). In 1789, Captain William Douglas arrived with the British ship Iphigenia, and the reef was later named Douglas Reef. In 1796, the brig Nautilus under Captain Charles Bishop re-discovered it, leading to the name Nautilus Rocks. Japan likely did not know of the atoll until 1888, and after investigations by the navy ship Manshu in 1922 and 1925, Japan declared it territory in 1931, naming it Okinotori Island. During 1939 and 1941, construction began for a lighthouse and meteorological site but was interrupted by World War II. After Japan's defeat, the United States assumed sovereignty over the Ogasawara islands, returning authority to Japan in 1968. Between 1987 and 1993, the government built steel breakwaters and concrete walls to stop erosion, leaving only three of the five rocks present in 1939 above water. In 1988, the Japan Marine Science and Technology Center built a marine investigation facility on a stilt platform in the lagoon, which also serves as an EEZ observation post with radar and sensors. A light beacon was installed by the Japan Coast Guard on March 16, 2007. The waters around the reefs are potentially rich in oil, minerals, and fisheries resources, and the area has military significance. Geologically, the islets are a coral atoll on the Kyushu–Palau Ridge, part of the Izu–Bonin–Mariana Arc system. The original Spanish name Parece Vela is used for geological formations such as the Parece Vela megamullion and basin. The three islets—Higashi-Kojima, Kita-Kojima, and Minami-Kojima—are now completely artificial, encased in concrete. The lagoon is 3 to 4.6 meters deep, with a small boat channel in the southwest.

Reader's Guide

Okinotori's significance lies in its role as a geopolitical flashpoint over maritime boundaries. Japan argues that the atoll is sufficient to claim a 200 nautical mile exclusive economic zone (EEZ), but China, South Korea, and Taiwan dispute this, asserting that the atoll does not meet the definition of an island under the United Nations Convention on the Law of the Sea. To maintain its claim, Japan invested heavily in concrete encasings and breakwaters, spending $280 million to prevent erosion and submersion. The atoll's dry land area is almost entirely artificial, consisting of three concrete encasings and a stilt platform housing a research station and EEZ observation post. The platform, built in 1988, includes radar and sensors to monitor activity in the zone. The atoll's history of multiple names—Parece Vela, Douglas Reef, Nautilus Rocks, and Okinotori—reflects its contested and remote nature. Its geological features, including the Parece Vela megamullion, are of scientific interest, but its primary legacy is as a symbol of territorial and resource disputes in the Philippine Sea.

Did You Know?

• At high tide, one area of the reef is only 1.58 m² (17.0 ft²), roughly the size of a twin bed, and rises just 7.4 cm (2.9 in) out of the ocean.
• The atoll was first named Parece Vela, Spanish for 'looks like a sail', by Miguel López de Legazpi in 1565.
• Japan has encased the reefs with $280 million worth of concrete to prevent erosion and maintain its EEZ claim.
• The research platform in the lagoon is 100 by 50 m (330 by 160 ft) and has a helicopter landing pad.