Land area: 21,958 ha
Designated on 15 May, 1972
Diving into the very transparent sea, one enters the richly colored undersea world. Reef-building coral grow in different shapes and a variety of fish swim between the reefs. Schools of fish in red, purple, blue, yellow and other bright colors show the rich ecosystem of the sea.
Iriomote-Ishigaki National Park is the southernmost park in Japan located in the south of Okinawa main island. It consists of major parts of Iriomotejima and Ishigakijima Islands in the Yaeyamashoto Islands, which mark the southwestern end of Japan, some smaller islands around them, and the broad sea area with coral reefs that lies between the two islands.
Iriomotejima Island is the second largest island in Okinawa Prefecture after the Okinawa main island with an area of 289 sq. km. In the center of the island lie mountains 400 ? 500 m in height and 80% of the island is covered with thick evergreen broad-leaved forests. It maintains pristine wilderness and therefore has high scientific value. Since the lower reaches of the major rivers are wide, on the Urauchigawa and Nakamagawa Rivers, sightseeing boats run from their river mouths for several kilometers upstream.
Ishigakijima Island has an area of 229 sq. km and is the center of economy and transportation in the Yaeyamashoto Islands. There are many places of interest such as mountains, including Mt. Omotodake (526m), which is the highest peak in Okinawa Prefecture, mangrove woods on the coast of Nagurawan Bay, and Shiraho and other sea areas where coral reefs grow.
On Iriomotejima Island, large communities of mangroves grow in areas along the deep bay and at the river mouths. The mangrove community at the lower Nakamagawa River is the largest in Japan with an area of 105 ha. Next to the community lie hydrarch woods of Sakishimasuonoki (Heritiera littoralis) which are known for their buttress roots. These woods have a strong tropical atmosphere with fern and fern relatives growing thickly. At the middle reaches of the Nakamagawa River and Hoshidate in the western part of the island, there are communities of Yaeyamayashi (Satakentia liukiuensis) of the palm family. They are found only on the Ishigakijima and Iriomotejima Islands.
While the plains in the coastal area on Ishigakijima Island are well-developed, natural forests of sudajii (Castanopsis sieboldii) remain in the mountainous areas in the central and north parts of the island. Off shore, coral reefs grow. In Yonehara, Yaeyamayashi grow naturally and in Hirakubo, there are wild growth areas for critically endangered shitan (Pterocarpus indicus).
Iriomote wildcats, an endemic species to Iriomotejima Island, are considered to be the symbols of the island. As their population is very small, further conservation measures are needed. Regarding birds, there are some species which can be seen only on the Yaeyamashoto Islands in Japan, such as crested serpent eagles. There are also many Amphibia, reptiles and insects which are endemic to the islands.
Sekiseishoko Lagoon, which lies between Ishigakijima and Iriomotejima Islands, is a shallow, calm sea area in which many coral reefs grow. Most islands in the lagoon including Taketomijima and Kuroshima Islands are small, flat islands formed by the upheaval of coral reefs. Unlike Iriomotejima Island, these islands have been well-developed and don't maintain much of their primeval wilderness, but they still have beautiful sand beaches and coral reefs. Taketomijima Island is known as a treasure trove of folk art and efforts are being made to conserve the landscape of traditional settlements. The area has great cultural value as well.
There used to be more than 360 species of coral reefs in the sea area but they have deteriorated considerably. Measures are being taken to recover coral reefs in this area.