TOURISM AND CONSERVATION AT WAITOMO CAVES, NEW ZEALAND
INTRODUCTION
The Waitomo Caves (Figure 6) are located in a series of Oligocene limestone underlain by a Mesozoic greywacke basement. Step faulting has resulted in repeated limestone outcrops in which numerous caves have developed. More recent Quaternary volcanic ash covers much of the area and has resulted in the infilling and burying of many cave systems. The climate is warm temperate with a mean annual temperature of about 13°C with few extremes. Rainfall averages around 2000 mm with a winter maximum. The topography of the Waitomo stream catchment varies from 462m (1500ft) at the steeply dissected headwaters of the Waitomo stream to around 60m (200ft) above sea level at Waitomo village. The approximate area of the catchment is 43 square kilometres. The original vegetation of which less than 25% remains was mixed podocarp - broadleaf temperate rainforest. Most of the natural vegetation was converted into exotic grassland pasture at the beginning of the century. Pre-European Maori knowledge and use of the caves was limited by spiritual and mythical fear of the unknown. Glowworm Cave, the main tourist attraction, was first explored in 1887 and surveyed in 1889. Its attraction was soon recognised and the large numbers of visitors and resulting damage to the cave prompted the Government of that time to acquire the caves from the Maori owners in 1904. After the construction of steps and walkways through the cave guided tours commenced around 1907. The main attraction of the caves is the large number of the bioluminescent insect Arachnocampa luminosa better known as the New Zealand Glowworm. Ruakuri Cave 3km past Glowworm Cave has a long history as a burial site and is the second longest cave in New Zealand with a total length of around 12 kilometres. It was acquired from the Maori owners in 1904 together with a large amount of native bush reserve. Aranui Cave was found in 1910 in the same reserve, it is the shortest of the tourist caves but undoubtedly the most attractive, its value was immediately recognised and guided tours commenced within 12 months of its discovery. Aranui Cave and Ruakuri Cave are separated by an assembly area and about 300m of bush walks.
TOURIST OPERATIONS TODAY
Waitomo Caves village is 8km off the main north-south highway and about 2 hours from New Zealand's largest city Auckland and the same from New Zealand's tourist capital Rotorua. Its geographic location allows easy "call-in" access to most North Island travellers. Over 250,000 people visit the caves annually with the vast majority touring Glowworm Cave only (86%) and only a small proportion (14%) visiting all three caves. 51% of all visitors are independent travellers, 49% on organised coach trips. Around half of all visitors are from New Zealand. Tours of up to 50 people are guided through the caves at regular times except during busy periods when tours commence as numbers total 50. Tours average 45 mins in each cave. Eight permanent guides are employed, these either live-in at the Waitomo Hotel or live locally. Another five temporary guides are employed over the summer holiday period. Adjacent to Glowworm Cave is the Waitomo Hotel, an old and impressive building originally built in 1908 to cater for caves visitors at a time when most visits meant an overnight stay. The hotel today caters to the luncheon trade and the overnight visitor wanting more elegant accommodation. The overall administration of the caves and hotel is vested in the Tourist Hotel Corporation, a body set up by the New Zealand Government in 1957 to foster tourism in New Zealand. Much advice and assistance in the running of the caves and reserves is given by other government departments and interested bodies such as the New Zealand Speleological Society.
WAITOMO CAVES RESEARCH PROGRAM
By 1974 it was apparent that 70 years of almost constant use as well as severe modification to the natural environment of the Waitomo district was having an adverse affect on the caves. In that year the Waitomo Caves Research Program was instigated with up to $15,000 a year budgeted for research. Paul Williams, Professor of Geography at Auckland University and President of the New Zealand Speleological Society was appointed Director. Other members of the group came from various governmental and university departments and representatives from the Tourist Hotel Corporation including the Corporation Secretary. The majority of members had a speleological background. The first task of the Research Group was to identify the conservation problems affecting the caves. Post graduate scholarships were then established and researchers recruited from U.S.A., Britain, Australia and New Zealand. Research is directed at both cave restoration and continuing preservation with the ultimate aim of providing a comprehensive scientific foundation to base future management and planning. In the five years since the beginning of the Research Study Group much work has been done and recommendations implemented often with impressive results, new areas of research are also being investigated.
Figure 6: Waitomo Caves Reserves
SPECIFIC RESEARCH PROJECTS
- Control of CO2
It is now well established that CO2 exhaled by cave visitors causes corrosion of speleothems when concentrations reach more than 2,400 ppm or around 7 times the CO2 content of cave atmosphere. This problem occurs in the Organ Loft of Glowworm Cave following a rapid build-up of CO2 when visitor densities exceed 100 persons per hour. Recordings have been made of CO2 well above corrosive levels and reaching concentrations dangerous to visitors. Ventilation of the Organ Loft by drilling a shaft to the outside and by mechanical means were investigated and ultimately rejected, it was found the easiest solution to the problem was to close off the Organ Loft before the CO2 accumulated.
Caves Cleaning
- Lampenflora
Artificial lighting inside caves enables primitive photosynthetic plants (algae mosses and ferns) to grow. This lampenflora was both environmentally and aesthetically unacceptable and had to be removed. Various forms of lighting were investigated as was the use of chemical sprays, the latter, particularly a 3-5% solution of calcium hypochlorite, was found to be the safest and most effective means of controlling the problem. Naturally occurring plant communities around cave entrances have been preserved along with some lampenflora communities for future reference or study. It was found that the growth of plants inside caves is directly proportional to light intensity and duration and it is now a general policy of cave management to use the minimum amount of light for the least amount of time.
- General Cleaning
Every visitor to the caves carries in small dust particles which accumulates along with airborne dust from roads and paths. Residues from the early use of candles, kerosene lamps and magnesium flares are still evident on horizontal ledges in the cave. Experimental cleaning with variable pressure steam jets has produced spectacular results and the planning of a major clean up of Glowworm Cave has now commenced. The major clean-up will be followed by regular and frequent cleaning of walls and formations. Any cleaning operations have to be consistent with glow-worm ecology and cave fauna in general.
- Lampenflora
- Sedimentation and Hydrology
The most serious impact of human modification to the natural environment of the Waitomo district has been the sediment build-up within Glowworm Cave. The natural rate of sediment build-up has been increased sharply by the widespread deforestation of the upper Waitomo valley in the last 80 years. An even greater build-up has occurred following major roadworks in recent years. This causes several present day problems.
Flooding which destroys glow-worms and closes the caves to visitors, has probably increased in frequency and duration since the turn of the century. Summer low levels causes boats to ground in summer necessitating expensive and possibly damaging desilting. Hydrological studies when completed will provide information on the long term effects of sedimentation.
- Glowworm Ecology
A detailed study of glowworm ecology is now under way. The conditions which encourage glowworms to inhabit caves are being identified preserved and enhanced where possible. Techniques of population counting, glowworm transplanting and increased food supply are being developed and used where necessary. Other cave operations such as cleaning and desilting have to be consistent with glowworm ecology.
RESERVES AND NON TOURIST CAVES
The Tourist Hotel Corporation at Waitomo administers around l0 sq km of Reserve Land most of which is classified as Scenic Reserve. The main feature of the reserves are the temperate rainforest natural vegetation in rugged limestone topography dissected by streams and waterfalls. Walkways total about 3.5km and give all types of visitors including caver's access to various features in the reserves. Preservation of the reserve is not only important for scenic values but for erosion control and to speleothem formation within caves. The biggest single threat to the reserves is from over-grazing by domestic and feral animals. Sheep and cattle from adjacent farmland often wander into reserves and are herded out or in some cases shot. Goats both wild and domestic are the biggest problem, efforts are being made to control goats by culling and fencing. The damage done by grazing animals in the lower forest levels is complemented in the upper levels by introduced oppossums, these animals are classified under law as "noxious animals" and are controlled by shooting, trapping and cyanide poisoning.
The indigenous fauna in the Waitomo district has suffered greatly at the hands of man particularly since the turn of the century. The larger fauna was dominated by many species of birds many skeletons of which are found in the caves. Many species have become extinct and others face extinction as the forest cover continues to diminish. The very rare long-tailed bat is occasionally seen in the reserves. Of special interest in the reserves are the many caves including sections of New Zealand's longest cave Gardners Gut. The conservation of these caves has in the past been left to individual caving groups and although there have been some damage the caves generally have not suffered from the severe destruction experienced overseas. The Tourist Hotel Corporation is willing to cooperate with the New Zealand Speleological Society to control and encourage the enjoyment of these caves by conservation minded cavers. It is interesting to note that by law the public is guaranteed right-of-access to scenic reserves and caves at all times subject to any restrictions or conditions which may be necessary for the preservation of natural features.
MANAGEMENT PLAN
Under the Reserves Act 1978 all controlling bodies of reserves are bound to produce a management plan for those reserves. The scope of this plan has been extended to cover a much greater area specific to the caves. The important basic principle is that the management plan is not a definitive design document but a statement of objectives and policies by which specific proposals are assessed. It is hoped to involve other government departments, interested bodies and the public in general in the planning process. A classification system is to be developed to identify the resource and conservation needs of every tourist and non-tourist cave.
SUMMARY
Over a period of seventy years Waitomo Caves have developed into one of New Zealand's most popular tourist attractions. Changes within the caves caused by tourism and modifications to the natural environment of the greater Waitomo district resulted in noticeable deterioration of the caves. A research program was set up in the early seventies and the management of the caves put on a more scientific foundation. Progress has already been made and with the formation of a comprehensive management plan a future based on the optimum balance between conservation and tourism is assured.
BIBLIOGRAPHY
JOHNSON, K.A. Botany Department, Auckland University. "Studies on Control of Lampenflora in the Waitomo Caves. "
MCCABE, B. Chemistry Department, Waikato University. "The Geochemistry of Cave Water."
PUGSLEY, CHRIS. Zoology Department, Auckland University. "The Ecology of the N.Z. Glowworm. Arachnocampa luminosa in the Waitomo Caves."