Glow Worms and the Waitomo Caves

No Cameras are allowed in the caves therefore no  photographs inside by me but a couple emerging from the darkness into the light. Perhaps this all added to the atmosphere.   The photos of the inside are taken from the website.

We entered into the very white cavernous limestone caves with their stalagtites and stalagmites and lit only by an occasional LED light and slowly descended down into a very dark space. At the bottom of steps we felt our way into a  rowing type boat holding circa 20 people, rows of four on a bench.  I could just make out a rope above our heads which the guide, standing behind me,  used to pull us along the river and underneath the gloworms. 

It was totally silent and lit only by the gloworms. They looked somewhat like stars twinkling in a very dark night sky although we were able to discern their movements, a sort of quivering. They were perhaps only 18/20mfeet above our heads. 
 

I immediately thought of stygian caves and Hades travelling down into the underworld.  I was just a little concerned that they might fall on my head knowing that they are indeed very slimy! I also know that some of my fellow travellers were feeling somewhat tense re the concern about earthquakes and being in such an enclosed and deep, dark space. We sat silently as we glided along through the darkness. You could almost feel people holding their breath.

A bit of research unearthed the following which I have added as further info.

“….A radiance became manifest which absorbed the whole faculty of observation—the radiance of such a massed body of glow-worms as cannot be found anywhere else in the world, utterly incalculable as to numbers and merging their individual lights in a nirvana of pure sheen…… To bow the head in adoration of Beauty was but to meet its whole shimmer reflected, unwrinkled, in the quiet river below.” In such eloquent language does a distinguished visitor to New Zealand describe those glittering tabernacles of the underworld, the Waitomo Caves”  E J Barrett.

The Caves lie in the heart of bush-clad hills seven miles from the Hangatiki Railway Station on the Main Trunk Line.

These caves rank high amongst the great natural wonders of the world and every year their popularity as the Mecca of the tourist becomes more firmly established. To how many of the thousands of visitors who have made the boat journey upon the silent underground river which flows through the famous Glow-worm Grotto, has not the question of the “how” of the wondrous radiance of this grotto suggested itself? Stalactites, gorgeous in their mantle of tiny lights stretch down from the roof of this grotto, from which again myriads of similar lights shine down on the tourist. This wonderful radiance is produced by living organisms.

The phenomenon of light production in the animal kingdom is one of very great interest and has occupied the attention of investigators for many years. The glowworms belong to the group of insects which have special light-producing “photogenic” organs. These organs are situated near the apex of the abdomen, or along the sides of the body of the insects in which they exist. The structure of the light emitting organs consists of an outer (light emitting) layer, and an inner (reflective) layer. Delicate trachae (breathing tubes) and nerves connect one layer with the other. The external covering or skin of the photogenic organs is translucent. A microscopic examination of the reflective layer of these organs reveals the cells of which they are composed as containing urate crystals which act as a barrier to the internal dispersion of the light.

Though called glow-worms, they are not, in reality, worms at all. The glow-worms of the Waitomo Caves are the larvae of flies of the fungus gnat family. The larva of this fly (the glow-worm) is a very delicately constructed little creature, which, when full grown, is anything up to 1 ½ inches in length. Like most larva of flies its body is segmented and semi-transparent. The glow-worms attach themselves by a fine horizontal thread to the roof of the caves in which they are found. This thread is tubular in structure, and being adequately lubricated by a substance produced and exuded by the glow-worms, these  little creatures glide backwards and forwards within it as the conditions of safety and danger dictate. From the main thread described, the glow-worms will send out as many as fifty vertical threads measuring up to two feet in length.

You can also view a very short video here about the caves and the gloworms: 

http://www.waitomo.com/glowworm-video.aspx