Christmas Island, Australia Photograph by Masatomo Fujiwara   Indian Ocean Islands southwest of the island of Java in Indonesia Tropical and Subtropical Moist Broadleaf Forests   50 square miles (100 square kilometers) -- about the size of Washington DC Critical/Endangered

· Tropical Atolls and Red Crabs
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Tropical Atolls and Red Crabs

A visit to these islands would provide an excellent opportunity to see several different island ecosystems. The Cocos Islands offer a glimpse of a classic atoll, in which a volcanic island is submerged and becomes engulfed by coral reefs, leaving a large lagoon where the crater once rose. These islands are somewhat isolated, but they have not escaped human modification. Christmas Island, on the other hand, is covered in forests and crawling with red crabs. Millions of crabs burrow and feed on the floor of the rain forest and play a major role in shaping this forested landscape.

Special Features

The Cocos Islands lie about 625 miles (1,000 km) southwest of Java, Indonesia, while Christmas Island lies just over 225 miles (360 km) south of Java. Both are of volcanic origin. However, while the Cocos Islands have submerged to form atolls, Christmas Island is the peak of an ancient volcano that rises 16,500 feet (5000 m) from the ocean floor--rising over 1,000 feet (350 m) above sea level. The climate on the islands is tropical, with temperatures averaging about 80° F (26° C) and the humidity lingering between 80 and 90 percent. These islands are frequently battered by catastrophic cyclones, which can have severe effects on the vegetation. Endemic species are common on Christmas Island, but few exist on the Cocos Islands--probably because they are low-lying and their total areas is only 5.6 square miles (14 sq. km), which makes them vulnerable to cyclone damage.

	Red crabs can weigh up to one pound and can reach densities of over one crab per 4 square feet (2.6 per m2).

Wild Side

If you visited the forests of these islands, you would probably notice that the forest floor is almost completely barren of leaves, seeds, or seedlings. This is more pronounced on Christmas Island, where more than100 million red crabs scour the surface of the island for anything edible. On the Cocos Islands you would have a chance to see at least nine species of land crabs scuttling across the ground--including coconut crabs and the Christmas Island red crabs. Each fall on Christmas Island, the red crabs migrate to the coast where they mate and lay their eggs. Other inhabitants include one of the rarest owls in the world--the Christmas Island hawk owl--as well as a number of other rare and endemic creatures including the Christmas Island frigatebird, the Christmas Island imperial pigeon, the Christmas Island white-eye, Abbott’s booby, the golden bosunbird, and the Christmas Island fruit bat.

Cause for Concern

Phosphate mining is the number one threat to the habitats of Christmas Island. However, most of the island has been designated as a national park. Coconut plantations have replaced native forests across much of the Cocos Islands, resulting in the disappearance of most native terrestrial wildlife. Poaching and other human activities also threaten the wildlife of these islands.

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