CAVE DESTRUCTION THROUGH MANAGEMENT - CRYSTAL CAVE, YANCHEP
INTRODUCTION
Crystal cave (YN 1) was discovered in 1903 by Henry White. It was developed as a tourist cave and opened to the public in 1933. Extensive works have been carried out in the cave over a long period of time. Unfortunately much of this work has been to the detriment of the cave. The cave has been managed by a series of government departments since it was developed as a tourist cave and their lack of management expertise is evident by the number of man made structures in the cave.
CAVE MORPHOLOGY
Over the years a number of small rocks have fallen from the cave roof and several rocks have been declared unstable by mining engineers called in to inspect the cave after minor rockfalls. It must be stated that the Yanchep Cave is developed in aeolian calcarenite, one of the 'softest' limestones in the world. Furthermore the cave contains a flowing stream which is obviously still altering the cave. These two factors together with mining engineers poking the roof with a long pole to determine cave stability have insured that some very unusual structures have been built in Crystal Cave.
MAN-MADE STRUCTURES
The first man made structures are encountered in the entrance chamber. Two large (about 0.5m x 0.5m x 2m high) concrete pillars, with the name of the cave emblazoned upon one of them in broken cave formations, are the first sign that major construction work has been undertaken in the cave. These two pillars are obvious in the cave map (Figure 1) as is the next even larger concrete column that dominates the exit from the entrance chamber to the wooden and concrete pillared passage that follows. Passing six wooden pillars and two concrete pillars on the concrete floor to the wooden staircase the visitor is surrounded by man made structures apparently ensuring their safe passage. It is almost certain that the pillars are not holding the roof up! The enlarged tunnel that follows enters an area that has a complete wooden roof with eight pillars along the walls. This structure provides entry to the large lake chamber in the cave.
This chamber has been severely altered by cave managers over the years. A large tree root dominates the view as the lake chamber is entered but unfortunately this is despoiled by the two concrete pillars and two wooden pillars that are also adjacent to the tree root. The quantity of man made structures in this chamber is overwhelming. Almost every wall in the chamber has been 'built'. Handrails stop visitors failing in the lake and a large rock staircase lifts them to the top of the chamber. The water flow in the 'lake' is directed through pipe beneath the walkway.
The visitor leaves this chamber through a man made tunnel which is full of concrete and wood. This tunnel leads to the largest chamber in the cave. At the eastern end of the large lake chamber a beautiful view of stalactites over a small lake (the Jewel City) awaits the visitor. A large rock staircase with concrete pillars is the 'holding area' for this view, as generally the entire party cannot view the Jewel City at one time.
Leaving the Jewel City visitors are confronted by the most amazing construction. An earthquake shelter! This structure consists of a concrete floor and an arched roof of corrugated iron covered in small boulders. The effectiveness of such a structure is almost zero. If an earthquake occurred while visitors were in the cave the possibility that they were close enough to reach the shelter would be low. If large boulders fell from the roof then it is unlikely that the structure could withstand the rockfall. All in all the structure is an eyesore.
Proceeding through the shelter visitors pass the wishing well where visitors throw money into a small 'pool' beside the pathway. This pool is 'protected' by an alarm system to stop visitors stealing coins from the pool. After the wishing well visitors pass another concrete and wooden pillar while returning to the entrance chamber before exiting the cave.
CRYSTAL CAVE - THE MINE
The cave has been so severely modified by man that its overall person is one of a mine rather than that of a 'natural' cave. Visitors to the cave do not appear to be concerned by the considerable modifications to the cave. However cave managers need to be constantly evaluating management practices and their impact on the cave they manage. In the case of tourist caves it is important that they convey a strong awareness of the sensitive nature of the cave resource to visitors. If managers do not convey this message to visitors they cannot expect visitors to respect the cave environment.
Managers must be held accountable for their actions. It is clear that the turning of Crystal Cave into a mine has taken place over a long period of time at the hands of many managers. The current managers, the Department of Conservation and Land Management (CALM), need to address this problem with strong management decisions.
CONCLUSION
If Crystal Cave is to continue as the highest profile cave educational facility closest to the Perth metropolitan area, management should ensure that visitors are shown management practices that protect the cave while displaying the caves natural beauty. Come on CALM, take some advice from Australia's foremost cave management authority, the Australian Cave & Karst Management Association (ACKMA) and remove some of the man made structures in the cave and attempt to 'un-mine' the cave and return it, as close as possible, to its original state.
Figure 1: Map of Crystal Cave