C2
Corals in Okinotorishima Island

Okinotorishima is 1740 km south of Tokyo and far away from Japanese and other islands. The fauna of this island has been little known due to its remote and isolated location. In 2012, a list of corals in the island was published. A total of 93 species were recorded and this number is considerably small compared to other tropical islands. Possible reasons of low diversity are (1) low probabilities of larval dispersal from other tropical islands in the isolated situation, and (2) small areas of habitats suitable for corals. The island is now facing with a risk of submersion according to sea-level rise by global warming. A conservation program of reef-building corals is now in progress to protect the small island. (Takenori Sasaki & Hajime Kayane)

References

Kayanne, H. et al. (2012) Low species diversity of hermatypic corals on an isolated reef, Okinotorishima, in the northwestern Pacific. Galaxea. Journal of Coral Reef Studies 14: 73–95.