Biodiversity of New Caledonia

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The Biodiversity of New Caledonia, a large Pacific island group, is considered to be one of the most important in the world. The island supports high levels of endemism, with many unique plants, insects, reptiles and birds. The island has no native mammals except for bats, and no native amphibians. New Caledonia's biodiversity is threatened by introduced species, logging, fire, agriculture and urban development, and mining (nickel and other valuable minerals). It has lost several species since the arrival of man on the island, but none are thought to have become extinct since 1500.

1 Evolution of New Caledonian Biodiversity
2 Elements of New Caledonian Biodiversity
3 Biodiversity of Flora
4 Faunal Biodiversity
5 Threats to New Caledonian Biodiversity
6 External links

[edit] Evolution of New Caledonian Biodiversity

Unlike many of the islands of the South Pacific, New Caledonia is not of volcanic origin, instead it is a fragment of the ancient continent of Gondwana. It separated from Australia and New Zealand during the break up of the super-continent, from Australia at the end of the Cretaceous (65 MYA) and from New Zealand in the mid-Miocene. This has led to a long period of evolution and means that New Caledonia’s fauna and flora comprise both dispersed species from Australia and other islands, and species whose ancestors were present on New Caledonia when it broke away from Gondwana. In many cases this long isolation has led to the evolution of not only species, but genera and even families that are unique to the island, or in some cases simply survive nowhere else. As the island moved north geologists assert that it was submerged at some times, botanists assert that there must have been some areas that acted as refugia for the plants that bear floral affinities with Gondwana. The rise and fall of sea levels caused by ice ages has led to islands being formed between New Caledonia and its neighbours, the Solomon Islands, Vanuatu, and Australia, this has helped species reach New Caledonia, and species of Gondwanan origin reach further into the Pacific.

[edit] Elements of New Caledonian Biodiversity

New Caledonia sits on the southernmost edge of tropical zone. Its main island, Grande Terre, hosts a variety of habitats arising from several factors, including geology, soils and altitude.

[edit] Biodiversity of Flora

New Caledonia plant communities are veritable living fossils, offering the opportunity to examine species with roots in the age of dinosaurs. Besides their antiquity, the flora of this island nation is exceedingly diverse, and includes a level of endemism, per square kilometre, seen almost nowhere else on earth.

[edit] Faunal Biodiversity

The Kagu represnets not only an endemic species but also New Caledonia's only endemic bird family, the Rhynochetidae.

New Caledonia's faunal diversity is similar to that of many islands, particularly New Zealand. It lacks land mammals (other than bats) instead having a vertebrate fauna dominated by reptiles and birds. Prior to the arrival of man some large species had evolved on the island that have become extinct, fossils found in cave deposits show the island once had a species of barn owl (Tyto letocarti), two extinct hawks, a megapode and a large extinct flightless bird known as Sylviornis neocaledoniae. The island also held a large terrestrial turtle unlike any today, armed with a clubbed tail and spikes coming out from its head. A terrestrial mekosuchine crocodile, Mekosuchus inexpectatus, was a component of the ancient Gondwanan fauna that also went extinct after the arrival of man.

Today the island has 21 endemic species of birds, including one endemic family, the Rhynochetidae, represented by one living species, the Kagu. The island is also home to the unusual tool-using New Caledonian Crow. See Endemic Birds of New Caledonia for a full list.

The island's reptile fauna shares most of its affinities with Australia. 62 of the 69 species are endemic to the island. Two species of snake are found on the island. It is the home to the world’s largest gecko, and a large number of skinks and geckos. No crocodiles or terrestrial turtles remain on the island.

[edit] Threats to New Caledonian Biodiversity

New Caledonia's biodiversity is threatened by a number of factors. Like many island biotas, its species were poorly equipped to deal with the destructive effects of the introduced rat, cat, dog and pig, which have taken a toll on native species like the ground-living Kagu. Hunting is still a problem in remote areas, but substantially greater concern arises from dramatic habitat-loss caused by deforestation due to logging, mining (one of the island's principal industries), uncontrolled fires (responsible for substantial destruction of large areas), agriculture (largely responsible for reducing the dry-sclerophyll habitat to a small fraction of its original area), and urban development.

Although no species are known to have become extinct since 1500, two species, the New Caledonian Rail and the New Caledonian Lorikeet have not been seen for over a hundred years and are considered to be critically endangered if not actually extinct. A similar fate was thought to have befallen the New Caledonian Owlet-nightjar, but a recent survey reported finding them in remote parts of the island.

New Caledonia is considered a conservation priority by many international organizations, which have lobbied and sought to work with the country's government to preserve the islands' unique ecosystems. Although their efforts have recently led to a few limited successes, to date they have failed to achieve definitive protection for New Caledonia's remaining natural areas. For instance, given the global importance of these living-fossil ecosystems, attempts have been made to recognize their significance by granting them UNESCO World Heritage Site-status protection. To date, no such attempted initiative has succeeded, due to opposition by regional governments, which are heavily influenced by mining and development interests (see below). Present-day mining operations continue, and are in fact being initiated, in localities of extreme ecological importance. World-wide public pressure has forced mining companies to recently begin voluntary, minimal post-mining rehabilitation. However, even when taking such rehabilitation efforts into account, mining activity still results in devastation of the extremely high biodiversity that had existed at the exploited site prior to the mining operation. Imposition of World Heritage Site-status would severely impact the pursuit of unrestricted mining activity in areas of ecological importance. However, this, in turn, could affect the economic well-being of the entire country, making a balanced, thoughtful approach essential to national interests.

Conservation efforts at the local, grass-roots level have been, at best, tentative, and have invariably failed when in direct conflict with mining (and other development) projects, due to the above-referenced importance of such projects to the country's comparative prosperity and stability. Recent, local political efforts to increase governmental priority for protection of the country's globally-recognized natural environment, met with strong official opposition, and violence against the proponents. Notably, Bruno Van Peteghem, recipient of the 2001 Goldman Environmental Prize, used the local court system to force government leaders to obey laws protecting the country's coral reefs. Despite his short-term victories in the courts, however, his home was firebombed, and his family and himself were repeatedly threatened. Ultimately, the head of government at the time, Jacques Lafleur, succeeded in silencing Bruno Van Peteghem's opposition, forcing him into de facto exile by arranging the termination of his employment with the national airline.