New Caledonia: Threats to Biodiversity

Article excerpt

New Caledonia is a French Territoire d'outre mer (overseas territory forming part of the French Republic) in the southern part of Melanesia, half-way between Australia and New Zealand. Unlike its neighbours Vanuatu, the Solomon Islands and Fiji, the island is not of volcanic origin but became separate from the great landmass of Gondwana 80 million years ago, whereas the 1,600-km barrier reef surrounding it and the three Loyalty Islands of Mare, Lifou and Ouvea were formed much more recently. A range of mountains runs down the centre of New Caledonia, which is nicknamed "le Caillou" (the Rock).

With an area of about 19,000 sq. km., the main island of Grande Terre is slightly smaller than Wales but has only 165,000 inhabitants, of whom 65,000 live in the capital, Noumea. It is a place of diversity in every respect, starting with population, since Kanaks, Wallis Islanders, Indonesians, Ni-Vanuatu, Arabs and Europeans live there side by side. It is ranked fourth in the world for its biological diversity and second for the extent of its coral reefs and atolls. It has 3,250 species of flowering plants (76% of them endemic to the island), 4,500 invertebrates, 148 birds and many species of reptiles such as turtles, lizards and geckos. But unfortunately this haven of wildlife is being gravely threatened by human activities.

The landscape is very varied. While the south and west of the island are relatively dry (1 to 1.5 metres of rainfall a year), average annual rainfall in the east is between 1.5 and 3.5 metres (and as much as 8 metres on the island's highest mountain, Mont Panie), and it is in that part of the island that the lush tropical vegetation, the thousands of streams, the famous colonial pines (of the Araucaria family), tree ferns and orchids are found.

RICH PLANT AND ANIMAL LIFE

According to the American non-governmental organization Conservation International, research carried out by botanists Norman Myers and Russ Mittermayer, the organization's President, show that New Caledonia is one of the richest places in the world in terms of biodiversity, and one of the places where biodiversity is most threatened.

The fauna of New Caledonia is typical of a remote island. There are many endemic species. Out of 116 species of nesting birds, 18 are endemic. The most extraordinary of them, the big grey woodland bird known as the kagu (Rhynochetos jubatus) is the country's emblem. Like the extinct Mauritian dodo, it is flightless and thus an easy prey for wild dogs and cats. Today, like the Hawaiian goose (Branta sandvicensis), it survives only because it is carefully protected, having been made the subject of an active conservation policy in 1990. Luckily for the bird, it is not a gastronomic delicacy and is not hunted, unlike the notu (Duculia goliath), the world's largest pigeon. The island is also home to the largest known gecko, the Rhacodactylus leachianus. As regards insects, 4,000 species have so far been recorded but no-one can tell whether this represents half or even a fifth of those actually living in New Caledonia. No thorough study of the island's fungi has yet been carried out.

The most serious threat to the island's vegetation is that affecting the dry (sclerophyllous) forest on the eastern side, of which only 2% remains, in isolated clumps. Its disappearance is due to the combined effects of forest fires, encroachment by grazing lands and urbanization, and introduced species such as the Timor deer (Cervus timorensis), the population of which has grown since the end of the last century to nearly 110,000 and which trample or eat the saplings, preventing any regeneration of the forest cover. The rainforest and scrub which cover 20% and 24% respectively of the territory represent the principal habitat of the endemic plant species (88% and 81% respectively). Some of these species are now only represented by a few specimens, while others have disappeared altogether. Conversely, a new species of wild rice (Oryza neocaledonica) was identified in 1994 near Pouembout, which goes to show that much remains to be done before a complete inventory is made. …