A JAPANESE expedition has started to create two coral islands in a storm-racked corner of the Pacific Ocean that seems destined to become a testing ground for renewed rivalry between Japan and China.

Japan has brought its scientific superiority to bear on the dispute over a cluster of rocks and reefs that defines the limits of Japanese maritime power and challenges Chinese expansion.

Marine biologists from Japan have just completed the first transplants of coral around a pair of islets, 1,060 miles south of Tokyo, to try to save them from waves and typhoons.

Eventually, said Kenji Miyagi, of the fisheries agency, they will graft millions of coral fragments on to the reefs to build them up above sea level and enlarge the surface of the islets, which sit just four inches above water at high tide.

The reefs were discovered by a British captain, William Douglas, on board HMS Iphigenia in 1789. They were named after him and mapped on the Admiralty charts long before anybody in Japan or China knew they existed.

Known in Japanese as Okinotorishima, or “remote bird islands”, they are critical to Japan’s interests today. Tokyo says they mark an exclusive economic zone extending 200 miles from these rocky outcrops.

Japan lays claim to resources that include fishing, minerals, oil and gas within the area. It has already spent more than £300m to build huge cement barriers encircling the islets. No less than £25m was lavished on a titanium net to protect one reef.

China disputes the Japanese claim, though even Beijing’s mapmakers, who like to enclose swathes of the South China Sea within their borders, do not assert that China has a right to the territory. Instead, the Chinese simply say that they are not islands, just rocks.

They argue that under the Law of the Sea, the Japanese therefore have no right to mark an economic zone there or to stop Chinese exploration.

The Law of the Sea states that an island is “a naturally formed area of land surrounded by water”. That is why Miyagi’s strands of coral, nurtured in laboratories on the island of Okinawa, are so important to maintaining Japan’s status quo.

Chinese survey ships have prowled the area, prompting diplomatic protests in Tokyo and a visit to the islets by Tokyo’s ultra-nationalist governor, Shintaro Ishihara, who stepped ashore waving a Rising Sun banner.

He kissed a plaque bearing the inscription “Okinotorishima, Japan”.

Then he snorkelled around the reefs and released a shoal of Japanese horse mackerel to promote the local fishing industry.

However, there is a sinister aspect to the rivalry. According to Yukie Yoshikawa, a scholar of international relations, the Chinese want to evict Japan so that they can have a free hand in the area in wartime.

“China wants freely to investigate its seabed for submarine operations in case of military conflict involving Taiwan,” she said in a paper for the Harvard Asia Quarterly.

The Americans support Japan in the dispute. If war broke out over Taiwan and the US intervened, its warships from Guam would probably have to sail across the area.

Additional reporting: Julian Ryall, Tokyo

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