|
Arthur's Pass National Park was created in 1929, the third
in New Zealand
|
Specific
references for this page:
Gerald
Cubitt and Les Molloy 1994: Wild
New Zealand. New Holland.
Craig
Potton 1998: National
Parks of New Zealand. Craig Potton Publishing.
The
Story of Arthur's Pass National Park 1986. Arthur's
Pass National Park.
Wild
New Zealand 1981. Reader's Digest
New
Zealand National Parks, 1979. Collins Nature Heritage
Series.
|
after Tongariro and Egmont. It covers approximately 100,000
ha (250,00 acres) in the central Southern Alps, straddling both
sides of the main divide although most of the land is on the
eastern side.
Arthur's Pass itself is the main crossing of the Southern Alps
by road and railway, linking Canterbury and Christchurch to
the West Coast. Completion of the railway line in 1923 made
the area easily accessible, and it became popular with excursionists
from urban centres in these regions. The creation of the national
park followed soon afterwards, in part motivated by fears that
such popularity would result in damage to the local environment.
Today Arthur's Pass National Park remains an easily accessible
alpine area with beautiful fields of alpine flowers, native
forests, and wild mountains. It is a special haven for trampers.
See below: Activities - What to see and do in Arthur's Pass National Park
Geological
setting
The rocks in Arthur's Pass National Park are primarily
greywacke and argillite (the Torlesse Supergroup), with the
transition to the Haast Schists well to the west of the main
divide.
See also Rocks
of the New Zealand mountains
The mountains are generally below 2000 m (6562')
east of the main highway (except for Mt Franklin 2145 m/7037',
and Mt Oates 2054 m/6739'). West of the highway 14 summits rise
above 2000 m, the most well-known being Mt Rolleston (2271 m/7451'),
Mt Harper (2240 m/7349') and Mt Murchison (2400 m/7874').
East of the divide the landscape shows some of the
classic features of the eastern Southern Alps: extensive scree-covered
slopes, and wide braided river-valleys (Waimakariri, Poulter
rivers).
The mountains and valleys of Arthur's Pass National
Park were heavily glaciated during the ice ages, and the land
has retained many distinctive glacial features, such as tarns,
cirques and hanging valleys. Nowadays, only about ten small
glaciers remain, mostly in the headwaters of the Waimakariri
River. All are smaller than 1 square kilometre (0.38 square
mile), and they are the northernmost glaciers in the South Island.
See also mountains
of New Zealand
The park does not stretch far enough westward to be in contact
with the Alpine Fault. However it is crossed on its north-western
boundary by the Hope Fault, a major component of the fault system
that links the Alpine Fault to the Kaikoura coast. The valleys
of the Taramakau, Hurunui, Hope, and Waiau rivers are aligned
in a straight line from south-west to north-east on the path
of the Fault. The area is tectonically active and earthquakes
have left their mark in the landscape. A fairly recent example
is the major landslide that occurred at Falling Mountain at
the head of the Edwards Valley, triggered by the Arthur's Pass
earthquake of 1929.
See also Tectonics
in New Zealand/Active faults
Climatic
conditions
New Zealand lies at the northern edge of the belt of low pressures
that circle the southern oceans (the Roaring Forties) from west
to east. This sets the general weather pattern in the Southern
Alps and the South Island, with a succession of low pressure
systems that bring strong westerly winds and bad weather, and
high pressure systems that generally bring gentler winds and
fine weather.
Cold and warm fronts can pass in close succession
and this results in a very changeable, unpredictable weather.
However this pattern does not preclude the occurrence of longer
periods of either good or bad weather.
The actual weather in the park results from the
effect of the mountains on the general weather pattern. The
Southern Alps force the moist air to rise and condense. Accordingly
on the western side of the mountains precipitation increases
from sea level to the summits of the main divide.
East of the divide the precipitation rate falls
sharply, due to the rain shadow created by the mountains.
Total annual rainfall is about 5000 mm (197 in.)
in Otira on the western side, 4000 mm (157 in.) in Arthur's
Pass Village on the divide, and down to about 1500 mm (59 in.)
at Bealey, 10 km (6 miles) south of Arthur's Pass Village, east
of the divide. As well as being drier, the eastern valleys have
also greater temperature extremes.
Daily temperatures may vary from above 30 degrees
C in summer to below freezing point in winter. Snow falls mostly
between June and September, but falls may occur at any time
of the year. Snow cover varies markedly from year to year, accupying
the ground above 1000 m (3280') between 3 and 5 months.
See also The
climatic influence in the New Zealand mountains.
Forests
The eastern valleys and mountain slopes up to about
1300 m (4265') to 1500 m (4918') are extensively covered in
beech forest. Mountain beech is the dominant species, but red
beech and silver beech are also common in places. In the larger
valleys the forest stops at the valley floors, which consists
of gravel with a sparse vegetation of tussock and the prickly
shrub matagouri. Generally the beech forests are fairly open
in the drier south-eastern parts of the park, with little undergrowth.
In the wetter areas close to the divide the beech forests are
more complex, with a variety of shrubs, ferns, mosses, lichens
and liverworts. Missing forest on eastern hillsides are usually
the result of fires from both Maori and European times.
As elsewhere in the Southern Alps the forest is
very different on the wetter western side of the main divide.
There are stands of beech forest in the Otira, Otehake and Taramakau
Valleys, especially red and silver beech. But on the lower hillsides
and valley floors podocarp forest is dominant, with rimu, kahikatea,
miro, matai, mahoe, kamahi, putaputaweta, broadleaf, pate at
lower altitude, and kamahi, rata, mountain toatoa, cedar, brodleaf
and ribbonwood at higher altitudes. The understory is rich,
including several species of Coprosma, several species
of tree ferns, vines, and epiphytes.
A particular feature of the vegetation in the park, especially
on the western side, is the zone of shrubland that makes the
transition between the forest and the alpine grasslands. There
the plant communities include dracophyllums, snow totara, mountain
toatoa, several species of Olearia (tree daisy), and
mountain flax. That vegetation can form a dense, interlaced,
closed mass, and pose difficulties to trampers. However the
shrub zone is more narrow and discontinuous on the eastern side.
The alpine
zone
Arthur's Pass provides easy access to a good sample of the rich
New Zealand alpine flora (New Zealand has more species of alpine
plants than forest plants, although 75 % of the land at least
was forested prior to human arrival, and most of them are endemic).
The lower part of this zone is dominated by species of tussock
(Chionochloa), especially snowgrass (the common name
for the taller varieties, including C. rubra, C. pallens,
C. flavescens). In between the tussocks there are a variety
of smaller plants. Among the best known and most conspicuous
flowers are the daisies (Celmisia), buttercups (Ranunculus),
gentians, spaniards (Aciphylla).
Birds
New Zealand has only one species of truly alpine bird, the rock
wren, which spends its entire life above the bush line, and
is found in Arthur's Pass National Park.
Keas are also found in the park above the bush line, but equally
in forested areas and down to Arthur's Pass Village where they
are attracted by human activity.
The forests provide habitat for a diversity of birds. Tuis,
kakas and New Zealand pigeons are more common in the western
forests, but other species such as yellow-crowned parakeets,
yellowheads and riflemen may be more numerous on the eastern
side. Other species of forest birds present in the park include
bellbirds, grey warblers, silvereyes, brown creepers, tomtits,
and moreporks. New Zealand falcon exists in the park in small
numbers, and the great spotted kiwi is present on both sides
of the divide.
Riverbeds provide habitat for a variety of species. Pipits,
paradise shelducks and Australasian harriers live there throughout
the year. In addition, the riverbeds attract migrant birds such
as South Island oystercatchers, black-fronted terns, banded
dotterels and Canada geese.
Birds of the streams and lakes include grey ducks, black teals
and black shags. Blue ducks exist in small numbers in the remoter
mountain streams.
Introduced
animals
Red deer, chamois and opossum are established in the park, while
Himalayan thar is rarely seen. Great efforts are being devoted
to control their numbers, as their browsing has a severely destructive
impact on the alpine and forest vegetation.
Short
and day walks
The road over Arthur's Pass gives
easy access to an alpine environment rich in interesting landscape
features, mountain scenery, forests, alpine grasslands, and
flower fields in season. From the vicinity of Arthur's Pass
Village there is a good choice of short walks, of various durations
(ranging from half an hour to a full day) and degrees of difficulty.
Among the shorter walks both the Devils Punchbowl
Falls and Bridal Veil tracks lead to spectacular waterfalls.
Dobson Nature Walk passes through alpine grasslands of tussock,
shrubs and, in season, alpine flowers. Cockayne Nature Walk
loops through some podocarp forest typical of the western side
of the divide.
Walks up to one day long lead into the alpine valleys
and to summits surrounding Arthur's Pass Village, such as the
Otira and Bealy valleys, and Avalanche Peak, Mt Bealy, and others.
Features of interest include high alpine vegetation, glacial
landforms (moraines, tarns) and fault scarps in places.
Some of these longer walks may involve river crossings,
and include steep or difficult sections.
Tramping
The mountainous terrain of Arthur's Pass National
Park, with long wild valleys linked by high passes, make it
an favourable area for tramping. The proximity of major urban
centres, ease of access by road and rail, and a good array of
hut and bivouacs, all contribute to its popularity among trampers.
A number of the main routes involve a crossing of the main divide.
Some of the easier routes, such as the Casey Saddle-Binser Saddle
and the Mingha-Deception, have tracks for most of the way, and
do not require potentially difficult river crossings. Most of
the tramping routes, however, have difficult sections, often
due to steep terrain, difficult or impossible river crossings
during heavy rain or avalanche danger in winter.
Mountaineering
The mountains of Arthur's Pass may not
stand among the best mountaineering places in New Zealand, but
they provide a range of opportunities and act as a good training
ground for mountaineers. The most popular summit
is Mt Rolleston (2271 m/7450'), which is close to the road and
can be climbed in one day from Christchurch. Most
other areas involve an approach of long tramps up valleys or
through bush and scree. The most serious climbing is located
in the upper Waimakariri River (on Mts Murchison, Harper and
Carrington, as well as Mts Temple and Rolleston), and on Mts
Franklin and Oates east of the Mingha-Deception valleys.
The rock is mostly greywacke, usually shattered
and loose, although there are good areas on buttresses on Mts
Temple, Philistine and Speight.
In winter there is good ice climbing in gullies
on Mt Temple, and on the Crow face of Mt Rolleston. The easier
slopes of Avalanche Peak and Mt Bealy are popular ground for
snow and ice practice.
Fishing
The braided bed of the Waimakariri
river does not provide good habitat for trout but there are
some large brown trout in its upper reaches. There is also good
back-country fishing in the Poulter River. In both cases tramping
experience is required.
|
