A feast of nature in our newest national park

Forest and Bird, Issue 280, 1 May 1996, Page 9

A feast of nature in our newest national park

JUDITH DOYLE

The creation of a new national park is rare enough in New Zealand so the opening this month of our 13th park Kahurangi is a

significant event.

goes tramping

in the Kahurangi high country.

AHURANGI is a wilderness — one of the largest unbroken, least modified landscapes in New Zealand. Most of it is derived from the former North-West Nelson Forest Park and extends from Farewell Spit to the Buller River. Here, some of our rarest birds can still be seen on the mainland. Biological curiosities such as giant snails and New Zealand’s largest native spiders live here and an incredible 1,000 or so native plant species — about 40 percent of all the native plant species in New Zealand and 80 percent of all our alpines. Kahurangi covers some 452,000 hectares and its geology is amazingly varied. In the west, there’s the granites. Then there are very old sandstones and other sedimentaries such as slates and shales. The central sedimentary belt is composed of conglomerates and debris from volcanos 500 million years ago. Further east, the marbles and limestones shape the land dramatically. This geological diversity leads to the extraordinary range of plants and variety of birds. We started a four-day tramp into the marble and limestone region of Kahurangi at the Flora carpark. A sharp-eyed member of our party soon spotted the rare blue duck, the whio. They are usually in pairs but this one was solo. It kayaked the Flora Stream for a bit, the splashing water drowning out its strange breathy whistle. Later we watched another rare bird — the kaka — using its strong, curved beak to hoist itself up the trunk of a beech tree, in search of honeydew. The kaka has to contend with wasps seeking the honeydew and possums eating the foliage. Perhaps our strangest encounter was Powelliphanta, the giant snail. Rated by scientists with the kiwi and the tuatara in biological importance, it has a shell like polished mahogany and the size of a toddler’s fist. But as we emerged from the

filtered light of the beech forest into the open country of the Arthur Tablelands, it was the flora that more and more demanded our attention. At first, it is the sculptural curves of the Astelia, their silver leaves glinting in the sun. There is a myriad of different hebes in this area, too, and the tracks are often lined with scarlet snowberries. As we climbed higher, clumps of gentians appeared. We were in Kahurangi in mid-February and this is the gentians’ time of glory. Their waxy-white flowers are luminous against the tussock. Climbing the shale and rock slopes of Mt Peel, we met little heaths; willowherbs growing on bare stones and a great variety of cushion plants clinging to the rocks. And then there is the exquisite South Island edelweiss, growing on the slopes of Mt Peel. Its tiny "cottonwool" petals are grouped round a furry gold centre with light grey leaves, the exact colour of the rock. Anyone who tramps in our high places is familiar with the mountain daisy (Celmisia). In fact the daisy family are kingpins in this area. The tree daisy can reach two metres in height. Then there is the showy snow Margue-

rite; the golden groundsel; the other Celmisia (there are 50-plus species); the little rock Haastia; the tiny edelweiss and even the famous vegetable sheep cushion plant — all members of the daisy family — New Zealand’s biggest family of alpine plants. Plants were at their most varied on the track from Lake Peel to the beech forest above the Cobb Reservoir. It is to this area that foreign botanists, interested in alpine plants, are often brought to see the widest variety in the one compact area. Deer and goats have taken their toll on the park although numbers have been reduced. We saw masses of hare droppings right up to the higher altitudes — another introduced animal. Animal pest control over the enormous area of the national park is a colossal challenge. Much of it is too inaccessible for trappers or hunters to be used. In the forest areas, aerial control is used against possums. "We have concentrated our wild animal control on the marble and limestone areas which have the greatest concentration of plant species," said Shannel Courtney, DoC’s senior botanist in the Nelson office. "We need to look at hare control as we suspect they have a

major impact on the alpine environment,’ he said. The tremendous plant diversity is due to the region being a meeting place of north and south. The North Island alpines can survive in the region and it is the northern extremity of the South Island alpine plants as well. There is also a weak botanical link between Taranaki and north-west Nelson. Some species, such as the coastal carrot, Oreomyrrhis minutiflora, are found only in the two regions and not in the Wellington area in between. "The two areas share other species which are also absent from the Wellington area," said Courtney. "The northern cedar; kauri grass; the wonderfulsmelling, large-leaved Alseuosmia and the trunked hardfern are found in Taranaki and also pop up again in northwest Nelson." This could be best explained by a former land bridge. Kahurangi has about 100 plant species which do not occur anywhere else at all. Some of these plants have a very specific habitat and this makes them extremely vulnerable. "The moonwort, for instance, a small alpine fern. At present, only 22 plants have been found, all in marble depressions," said Courtney. There has been momentum for a national park in northwest Nelson since the 1970s. It is now five years since the Conservation Authority set in train a national park investigation, and the proposed park has had to face court action from disgruntled electricity companies, Treaty claims and determined political lobbying before it could be gazetted. It is certainly cause for celebration that Kahurangi National Park, after a long and tortuous battle, has now become a permanent refuge for our unique bird and plant life. Judith Doyle is a freelance journalist from Wellington.