Noumea, New Caledonia: Restoring What Was Lost
The children’s hands, stained with soil, gently place a tiny sapling in the earth’s warm embrace, surround the tree with a mixture of gravel and watery gelatin, and spread a blanket of dirt on top. Sister, brother, and father admire their work as an old man carefully waters the grey ebony (Diospyros fasciculosa), one of the tree species of the island’s dry forests.
It is a small but powerful gesture for conservation on a hot day in March, as about 100 people, young and old, gather at the Noumea Zoo and Nature Center in this capital city. Modern descendents of French colonists and Melanesian seafarers, they have come here to help plant a nursery of native trees and shrubs that once covered their homeland for millions of years but are now facing extinction.
Island of the Rare
Biologically, New Caledonia is a world unto itself, an ancient chunk of the supercontinent Gondwana (comprising South America, Africa, Antarctica, Australia, and India) that drifted apart some 80 million years ago. Like some prehistoric Noah’s Ark, the main island of Grande Terre and its 11 surrounding islands, which lie 625 miles off the east coast of Australia, were inhabited for millennia by only plants, birds, insects, and a few lizards. This isolation allowed some species to follow unique evolutionary paths while others remained “living fossils,” surviving while their kindred species elsewhere in the world vanished.
The smallest of the
biodiversity hotspots, more than 80 percent of New Caledonia’s plant species occur nowhere else on Earth. Like many mountainous regions, the southwestern side of this French territory has a dry, almost Mediterranean climate, while the northeast remains lush with ancient plant species like tree ferns or immense conifers dating from the time of the dinosaurs. Both wet and dry forests on these islands brim with endemic species, many still unknown to science. Sadly, both have also been reduced to mere fragments of their former majesty by human encroachment.
Of the two, New Caledonia’s dry forests and maquis shrub lands are the most unusual and heavily denuded. These endemic sclerophyll or “hard-leaved” plant ecosystems have adapted to western Grande Terre’s six-month dry season and are capable of living in the island’s “ultra-basic” soil that is low in nutrients and high in toxic minerals like nickel, manganese, and chromium — conditions that would kill ordinary vegetation. They also survive in the more acidic sedimentary clay soils of the dry forest.
Even so, some 223 endemic species of flora thrive here, 60 of them exclusively in these patches of dry forest. And patches they are. Drive along the lonely highways of New Caledonia’s west coast and all you see are miles of open, grassy pastureland that rise to equally treeless slopes of the central mountain range that runs the length of the island.
According to Christian Papineau, who heads New Caledonia’s Sclerophyll Forest Program, dry forest covered most of the 7,000 square miles of Grande Terre’s western region thousands of years ago, but continued burning, overgrazing, and land clearing — mostly by French colonists over the past 200 years — reduced these mighty woodlands to a mere 1 percent of their former range.
“Fire has continued to be the number one threat to New Caledonia’s dry forests,” Papineau says. “Despite current government efforts to discourage burning, we still lose hundreds of acres every year. That’s an enormous and irreplaceable loss of biodiversity.”
Other
threats have come from an estimated 1,200 invasive plant and animal species introduced by humans over the centuries, ranging from agricultural grasses and livestock to accidental invaders like the little red fire ant (
Wasmannia auropunctata), whose aggressive nature and fiery sting have plagued native animal populations and halted a fledgling effort at establishing coffee plantations. A hundred and fifty years of open-pit mining for nickel and other heavy metals has also poisoned the land.
Rising from the Ashes
New Caledonia’s dry forests were a biological mystery until 1981, when French scientists first recognized this rich and highly unusual ecosystem. What was once considered worthless bush is actually a treasure of biodiversity. In 1996, a CI-sponsored Rapid Assessment Program of New Caledonian native forest tracts identified five key regions that were still relatively undamaged. This led to an international coalition to conserve the most important dry forest habitats and help New Caledonians understand their value.
Most New Caledonians don’t even know what the dry forest is, and Papineau hopes that education efforts like the tree planting event at the Noumea Zoo and Nature Center will help more people realize how special their island home truly is. “This is New Caledonia’s real wealth,” he says, leaning against a lofty grey ebony some 60 feet tall. “And it’s a heritage every one of us here must protect.”