Preserving the High Country

Forest and Bird, Issue 312, 1 May 2004, Page 24

Preserving the High Country

AINSLIE TALBOT.

The Crown purchase of Birchwood Station opens a huge area of South Island high country for New Zealanders,

writes

ravelling into the Ahuriri Valley in North Otago, it’s easy to understand why conservationists, trampers, climbers and fishers have long enthused about this outstanding high country. There are very few alpine valleys east of the Main Divide which are as scenic and as ecologically significant as this. Or as accessible — by a dusty, shingle, no-exit road that runs off the northern side of the Lindis Pass which links inland Canterbury with Central Otago. The Ahuriri is a delight. The countryside runs from wide, grassy, valley floors, with their mixture of tussock, introduced species, and extensive alpine wetlands, through thousands of hectares of dense beech forest, up to alpine tussock and shrublands and high alpine fellfields. Peaks like Mt Huxley and Mt Barth soar over 2000 metres with permanent snow and large glaciers. Through the centre of this stunning landscape flow the crystalclear waters of one of the best trout rivers in the country, the braided Ahuriri and its tributaries; Canyon Creek, Watson’s Stream, Hodgkinson Creek and Snowy Gorge Creek. The Ahuriri and its glistening mountains are a superb example of a glaciated valley landscape, an iconic part of New Zealand’s natural heritage. It would

have been a great loss if the public had been excluded forever because of private freeholding through the Crown tenure review process. The recent announcement by the Minister of Conservation, Hon Chris Carter, of the decision by the Nature Heritage Fund to spend $10 million purchasing the Birchwood property might be considered by some as somewhat extravagant. But this is a narrow economic view. Although this is the largest-ever

purchase by the Government’s conservation fund, the preservation of this unique alpine environment. with its exceptionally high conservation values, is a forward-thinking decision for New Zealanders. Ron and Jennifer Williamson and other members of their family have leased Birchwood from the Crown for 62 years, although leasehold tenure goes back to 1873. The Department of Conservation’s recommendations under the Crown lands tenure-review process led to Birchwood

being identified as a possible acquisition because of its outstanding ecological and recreational values; in fact it was initially considered in 1991. More recently though, obtaining this extensive 23,783 hectare leasehold property, has been encouraged and supported by Forest and Bird, Federated Mountain Clubs, Fish & Game, the New Zealand Deerstalkers’ Association, Public Access New Zealand and local tramping clubs. The concern of all parties was preservation and

protection of the landscape and ecology of the area, and providing public access — something that has not always been easy in the past, with the road running right through locked gates in the station’s stockyards. Dr Gerry McSweeney, national president of Forest and Bird and a member of the four-person Nature Heritage Fund, was delighted when the Minister of Conservation announced the purchase. ‘Birchwood is one of the crown jewels of the high country — there are very, very few properties like this, he says. "The Ahuriri itself is protected by a Water Conservation Order and is a superb trout fishery, one of the best in the country. This purchase

guarantees access to that, and the preservation of the important wetlands that feed the river. This could all have been under threat if new owners had taken over the place and locked it up. The property was on the market — it’s not a case of DoC gobbling up farmland, and I think it’s great that it has happened. He also makes the point that the money is not coming from DoC’s budget and therefore other conservation initiatives will not be affected. He says the Government is obviously interested in retaining key highcountry properties for the public, as has been shown by its recent decisions on Molesworth, and the Poplars Station in the Lewis Pass.

One of the important effects of the Birchwood sale, which comes into effect in July, is that cattle will no longer be allowed to graze the valley floor. Critically important wetland habitat and vegetation and riverbed will be enhanced for severely endangered species like black stilt, blackfronted tern, wrybill, and banded dotterel. The Ahuriri is also home to many other species such as pied stilt, oystercatcher, marsh crake, scaup, black-backed gull, black-billed gull and shags, which will benefit from enhancing these rare, alpinevalley wetlands. It is an interesting comment on species degradation that former owner Ron Williamson says 50 years ago there were around 70 black stilts on the property, but competition from Canada geese, stock disturbance and predation have seen these cut back to just seven today. DoC will be working hard to boost that population through predator control and its intensive captive-breeding programme based at Twizel in the Mackenzie Country. After all the Ahuriri should be perfect black stilt habitat. In fact the whole 30-kilometre-long valley and its beech forests have a wealth of bird species with at least 52 examples recorded in the last decade. The forests of mountain and silver beech are habitat for a wide range of birds: rifleman, grey warbler, New Zealand falcon, fantail, brown creeper, bellbird, pigeon, tomtit, cuckoo

and yellow-crowned parakeet, with kea and rock wren at higher altitudes. Nonetheless, according to Dr McSweeney, the forest margins have been badly damaged by cattle and grazing, with a distinct absence of young beech trees and undergrowth. There is also a lack of mistletoe up to two metres above the ground, again because of cattle which, like possums, love eating the species with its brilliant red flowers and succulent leaves. But with the removal of cattle this year, sheep within five years, and with few deer or rabbits, there should be rapid regeneration of forest margins over time. Birchwood and the Ahuriri Valley are important for other ecological reasons too. Professor Alan Mark, an expert on tussock land and alpine landscapes and also a member of the Forest and Bird national executive, extols the area as ‘highly significant’ because of its unbroken spectrum of high-country plant species and habitat, preserved from valley floor to mountain top. The Ahuriri is the closest thing we have to an untouched preEuropean alpine ecosystem in New Zealand. The valley floor is a mixture of short tussock, exotic grasses, mosses and lichens including the Mackenzie Basin’s only lowaltitude area of hard tussock Festuca mathewsii, with matagouri and other shrub species on shingle fans. Extensive and impressive swathes of mountain and silver beech forest meet the park-like valley floor on the western side in the lower Ahuriri, and cover both eastern and western slopes above the confluence of Watson’s Stream in the upper valley. Fire has destroyed much of the beech from the eastern slopes below

Watson’s Stream. The same has happened in the adjoining upper Dingle Burn Valley, also a part of the purchase, where burnt logs can still be seen in the grassland on the eastern slopes. In other areas there is a diverse range of natural subalpine shrublands, above the bushline, and in those places inaccessible to stock, or where forest cover has been destroyed by fire. The threatened Pittosporum patulum has been

identified in the Dingle Burn, Canyon Creek and Hodgkinson Creek. Above the bushline tall tussock and snow tussock dominate, sometimes reaching down to the valley floor, but again interspersed with scattered shrubs such as Dracophyllum longifolium. Surveys have shown that slimleaved snow tussock has all but disappeared in some areas because of grazing. In the high alpine areas cushion vegetation is found along with a range of other hardy species. The Ahuriri also contains three species of skink (spotted, McCann’s, and common) and two geckos (common and jewelled) and a range of invertebrates including eight species of butterflies. The river is a nationally important fishery for brown and rainbow trout, in a stunning high country landscape. Native fish recorded include several species of galaxias and upland bully.

The Director-General of the Department of Conservation, Hugh Logan, a mountaineer himself, says the Ahuriri area is a superb addition to public conservation land adjacent to the Ohau Conservation Area. This purchase, along with adjacent land obtained through the process of tenure review means there will be an additional 82,665 hectares of contiguous public recreational land in this area. Along with the Ohau Conservation Area, this points to the eventual formation of a new High Country Conservation Park. ‘The Birchwood purchase is a wonderful conservation asset for New Zealand and one of the great recreational areas in the South Island, enthuses Hugh Logan. ‘It has a superb range of opportunities, from short walks, to demanding alpine ascents, to wonderful fishing, and it’s all so accessible. On a fine day it’s quite superb; you've got mountains, big glaciers, and

beech forests, with a magnificent river running through, and five accessible huts. There was definitely overseas interest in this property, but in their hearts the Williamsons wanted it to stay in New Zealand. ‘We’re now in a transition phase and have got to take it step by step — you can’t just go from one regime to another on a property like Birchwood which has been farmed for 125 years, he says. "We’re committed to keeping it weed free and we'll do that, but the Department of Conservation has to watch how the place changes, and adapt to those changes as they come about. — AINSLIE 1 ’ prepared this article on behalf of the Nature Heritage Fund. See more of G\8! work on the website www.cleangreen.co. nz