During our circumnavigation of the island of Grande Terre, we had wanted to visit one of the rain forests and explore the many plants that are closely related to those that we have come to know so well in New Zealand and Tasmania, as well as Argentina. The Riviere Bleue Provincial Park is only 50 km from downtown Noumea. It contains areas of virgin forest and giant trees, as well as areas that are growing back from damage due to lumbering and mining at the turn of the century.
New Caledonia flora is particularly rich and diverse. There are more than 3,000 plant species, 80% of which are endemic to the country. Thirty-seven species of palms endemic to New Caledonia are currently known, growing at a wide range of altitudes. Tree ferns, Kaori trees and Hoop trees grow to 30 m in height.
Translating from “Fleurs et Plantes de Nouvelle-Caledonie”:
“The flora of New Caledonia is some of the most extraordinary in the world. … “The ultrabasic soils in some areas are poor in phosphorus, potassium and calcium, elements which are considered indispensable to plant life. In addition the soils are rich in metals such as nickel and manganese which are toxic to plants.”
Maquis minier, otherwise known as ultrabasic scrub, consists of shrubby vegetation growing on ultramafic soils and the growth-form of which is not influenced by altitude or rainfall. These plants are able to withstand the high concentrations of nickel in the soil by neutralizing it as organic acid complexes, thus reducing its toxicity. Long isolation has enabled the original ancient plant families to develop without the threat of being replaced by pioneering plants.
The maquis flora contributes significantly to the overall richness and distinctiveness of the new caledonian flora. The level of plant endemism (89%) is higher in maquis than in any other vegetation type and it is exceptionally diverse since it contains a third of all new caledonian species. Some of our favorites are the carnivorous pitcher plants and tiny sundews. The spring flowers were on display, showing their diversity and bright colors.
New Caledonia bird species are also numerous and varied. We heard constant bird song during our visit to the park. One of the most endangered is the Kagu, a beautiful flightless bird with powder blue feathers and crest. The driver of the van which took us to see the sites located north side of the river assured us that we would see a Kagu. About half way along the road, she stopped the van, got out, and began to quietly call, “Coco, Coco, Coco.” After a short while, she smiled and nodded towards the forest. Coming out from the underbrush was a perfect Kagu. The driver scattered a few bits of nourishment on the ground, and the Kagu walked cautiously out onto the road where we were able to admire it and photograph it. The Southern Province has been successful in captive breeding this bird, so the Park Riviere Bleue contains the largest number of Kagus of any area of New Caledonia. It was a rare treat for us.