Ogasawara Islands, Japan Photograph by Nobuyuki Uchimura   Japan Tropical and Subtropical Moist Broadleaf Forests   50 square miles (100 square kilometers) -- about the size of Washington DC Critical/Endangered

· Islands at Risk
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Islands at Risk

Far from the busy streets of Tokyo, Japan, lies a scattered string of small volcanic islands known as the Bonin Islands. On a map, they are easily overlooked, resembling tiny specks in the Pacific Ocean. But up close, you might wish more people had overlooked this area. Nearly 200 years of human disturbance have left little native forest behind. Still, where the landscape is the most rugged, forest patches remind visitors of the abundant beauty these islands once had.

Special Features

These volcanic islands range in temperature from an average of 64° F (18° C) in February to 77° F (25° C) in July or August. The topography is rugged, with some sea cliffs ranging from 164 to 328 feet (50 to 100 m) in height. Native forests are found only on the most remote and inaccessible parts of these islands. Vegetation types range from moist and dry forests in the lowlands to palm-dominated forests on dry, rocky montane slopes. Scrub forests can be found on mountain ridges and on the exposed tops of sea cliffs. These islands are known for their high degree of endemism. Out of about 500 plant species found here, almost 43 percent are endemic. Seventy-five percent of the tree species are native.

	The Bonin Islands are well known for their place in military history. They formed important links in the Japanese defenses during World War II, until the U.S. Navy seized them in 1945. The islands were returned to the Japanese in 1968.

Wild Side

The most common animal found here is not a native species roaming the forests, but an introduced goat. Grazing by goats has destroyed much of the islandâs native vegetation. The islands are now mostly covered in grasses, a secondary vegetation resulting from overgrazing. Elsewhere, stands of Leucaena trees form dense thickets, shading the forest floor and limiting the growth of other plants. No fewer than 58 rare species of vegetation can be found on the Bonin Islands, but 20 of these are considered endangered.

Cause for Concern

Many endemic plant species, especially orchids, are threatened with extinction because of human disturbances, goat grazing, and the introduction of non-native plant species. To combat these threats, however, the Japanese have protected large areas as national parks.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.