Landscape Analysis, Southern New Caledonia – by Gary

First light on our approach to Noumea found us gliding slowly through Canal Woodin, the narrow passage between the southern end of the big island of New Caledonia and the much smaller Ile Ouen.  Steep hills, thin vegetation, many bare eroding gullies, the exposed soil and rock glowing orange – we were threading a remarkable landscape, reminiscent of the hills round Queenstown, Tasmania.  Natural or man-made?  This was our point of debate as we sailed through.

The red lines and dots show our route around the southern end of the big island of New Caledonia en route to Noumea.

One of the more striking aspects of this landscape - no people!  Almost no direct sign of the activities of humans, apart from glimpses towards the head of Baie Du Prony of large scale mining activity.  And no sign of grazers; sheep, cattle, goats – so no culprits there. We knew New Caledonia to be highly mineralised; iron, copper and most particularly nickel, a key ingredient of stainless steel are all found here.  The mine we could vaguely discern in the poor light and distance was a huge new nickel ore extraction, concentration and export facility.  Could old mining and prospecting activity have created this landscape?  Could fire, that key tool of the old prospectors be causal?  Or perhaps it was just natural?.  Soil development was obviously highest at the bottom of slopes where vegetation was thickest, tallest and most luxuriant.  Higher up the thin soils are most obviously capable of supporting only light, windswept heathy looking vegetation that likely dries out quickly between rainfalls.  Could lightening strikes and subsequent hot fires have stripped vegetation and seedbeds, with erosion quickly following?

The soils were obviously deepest at the base of slopes, with pockets of luxurient growth, featuring the distinctive pines of New Caledonia (Araucaria columnaris).

A high speed ferry distracted us from our morning cogitations – we clocked it at 36.2kn on the AIS as it screamed past.

But back to our puzzle...  its not difficult to imagine fire being a major factor in the development of this landscape.

Up slope, lacking vegetation, erosion of the loosely consolidated substratum would be rapid.

We sought answers on arrival in Noumea, heading for the local library (itself a wonderful piece of history).  Piecing together our bits of French, English and more than a few hand waving gesticulations we were shuffled past a phalanx of shoulder shrugging librarians – those answers were looking elusive!  But miraculously we were rescued – a fellow standing in line behind us over-heard us and stepped in to help.  A miner by profession and a 'Caldosh', that is, a descendent of the original French settlers, Jacques' depth of knowledge of his island's history, landscape evolution and current practices was impressive.

In search of information, we headed for the local public library.  Itself a fascinating piece of history, this building commenced life as the New Caledonia Pavillion in the 1900 Paris 'Exposition Universelle', and was dismantled and relocated to Noumea afterwards.

As Jacques pointed out, the library site boasts a collection of  large, old trees, including on the left, a fine Kauri (same as grow in NZ).  It was the Kauri, along with many other prized forest trees, that apparently grew prolifically around the southern end of the island.  Jacques indicated that the first settlers, 150 to 200 years ago, rapidly harvested the trees for construction lumber.  As we speculated, fire, high rainfall and erosion did the rest.

Meanwhile most of the southern part of the island has been declared a national park and is quietly repairing itself.  It is in fact much, much greener than when I first saw it 30 years ago.

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