Japanese corals: Especially diverse, especially threatened

Posted on August, 01 2000

For years, the corals of Japan's Ryukyu Archipelago have been under threat from Crown of Thorn starfish infestation, soil erosion, direct destruction, and more recently, landfill plans for a new airport. WWF-Japan's first field research centre has now been opened to keep a continuous watch over the reefs' health.
Ishigaki, Japan: The 200 islands of the subtropical Japan's Ryukyu Archipelago or Nansei Shoto Islands swing down in a graceful arc from mainland Kyushu almost to Taiwan. Just about all of them have reef formations with more species of coral than on Australia's Great Barrier Reef in only a fraction of its area.

One of the conservation organization WWF's Global 200 sites, they also host hundreds of uniquely evolved species, such as the Okinawa rail (Rallus okinawae), discovered in 1981, and the Iriomote wildcat (Felis iriomotensis), of which fewer than 80-100 remain.

In the fringing lagoon at Shiraho, on Ishigaki Island, living coral domes as big as haystacks rise from a white sand floor. One seldom sees the same species of fish twice. The ceiling of low tide flattens off the tops of the larger domes, forming "micro-atolls." There you can find the largest, oldest colonies of blue coral Heliopora coerulea in the northern hemisphere.

This priceless ecosystem is threatened. It was here in 1979 that the government announced plans to build the new Ishigaki airport on landfill in this reef.

By the 1980s the reefs were in tatters from Crown of Thorns starfish infestation. Nor are the starfish the coral's only enemy. After Okinawa's reversion from the United States - who had occupied the area since World War II - to Japan in 1972, extensive public works were initiated to bring Okinawa's infrastructure up to the same level as the rest of Japan. The seashore was rapidly claimed for concrete harbours and factory sites, and the coral died from soil erosion and direct destruction. The research also found Shiraho was one of the few healthy spots left.

WWF-Japan and the Nature Conservation Organization of Japan funded a flurry of independent scientific surveys that culminated in exhaustive report presented to the World Conservation Union's (IUCN) General Assembly of 1988, and led to the adoption of a resolution calling on the government of Japan to protect Shiraho Coral Reef.

Since then, increasingly urgent calls have been heard both within Japan and throughout the world to protect the reef. The rising tide of citizens, scholars, celebrities and conservation organizations, both inside and outside Japan, finally halted the plan to landfill the Shiraho reef in November 1992. Despite this growing momentum to save the reef, it remains in danger.

When the landfill plan was withdrawn, it was decided that the airport would be built on land. Though clearly more attractive than the original plan, soil erosion from construction still poses significant danger to the reef. Equally worrisome are the continued calls to revive the landfill plan amongst the people of Ishigaki Island and the Okinawa Prefectural Assembly.

WWF International President Emeritus The Duke of Edinburgh lobbied actively for Shiraho's protection, and announced plans for construction of the WWF-Japan Coral Reef Conservation and Research Centre, in Shiraho village.

WWF-Japan needed 130 million yen (US$1.2 million) to buy the land and build the Centre. A successful fundraising campaign, launched in 1995, appealed to supporters to become honorary "Shiraho Coral Reef Villagers." By February 2000 over 5,500 "Villagers" had donated over 150 million yen (US$1.4 million).

The new Centre's main programmes involve field surveys and environmental education. Regular surveys keep a watch over Shiraho lagoon's health, and an all-island survey is carried out every five years. The Centre plans to expand ongoing surveys of soil runoff pollution, which will help deal with present problems, and in evaluating the new airport site, as well as in future restoration efforts across the archipelago.

The importance of local commitment, not just of a few but of a broad spectrum of island society, is essential for the goal of coral reef protection, at Shiraho, throughout Ishigaki Island, and the whole archipelago.

(698 words)

* Margaret M Suzuki is a member of WWF-Japan's Wetland Action Network.

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