The Ogasawara Region

Natural Characteristics

Okiike, located on Minamijima

Ogasawara is located 1,000 km (621 miles) south of Tokyo. The climate is subtropical, with an average temperature of about 23° C (73.4° F). There is little variation in the temperature throughout the year, and the area sees no frost or snowfall. The archipelago is made up of oceanic islands that have never formed part of any continent. For this reason, the Ogasawara Islands are home to so many endemic species of flora and fauna that they are called the "Galapagos of the Orient."
The archipelago consists of over 30 islands, including two inhabited islands, Chichijima and Hahajima. The majority of the archipelago is designated as a part of Ogasawara National Park, and many areas are designated as special protection zones, which are the most strictly regulated type of special zone. On Minamijima, which lies to the southwest of Chichijima, you can see the only submerged karst landforms in Japan, as well as sinkholes called dolines and sharply etched rocks called lapies.
In the winter and spring, dolphins and whales venture close to the shore, and in the spring and summer, green sea turtles come ashore to lay their eggs.
In 2011, the Ogasawara Archipelago was registered as a world natural heritage site.

Issues

Ogasawara is home to many endemic species, including endangered species and species designated as natural treasures. The ecosystem, however, has been disturbed by actions such as the theft of such species and the introduction of invasive species. Feral goats also cause the stripping of grasslands and the erosion of soil. Additional measures are needed to protect this invaluable world natural heritage site.

Green anoles

A green anole

Green anoles were first brought to Chichijima by humans in the 1960s, and to Hahajima in the 1980s. They can live in a wider range of habitats than the native Ogasawara lizard, and are now present in almost all areas of Chichijima and Hahajima. Because green anoles eat insects such as cicadas and dragonflies, the damage they cause to the insects of Ogasawara has also spread.

Lantanas

Lantanas were brought to Ogasawara from Hawaii in 1879. They grow in colonies at the edge of the forest and on the forest floor. Although it is unclear whether lantanas have any invasive or adverse impact in Ogasawara, they have been observed to encroach significantly on endemic species in Hawaii. Lantanas spread more quickly in moisture-rich soil, but can also grow and multiply in soil of any type.

These cute lizards and beautiful flowers have not always lived in Ogasawara. Invasive species such as these have an increasingly large impact on the precious native flora and fauna.

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