Cave Formations

Most New Zealand caves are formed from limestone and marble sediment. Enormous amounts of calcium rich mollusk shells and skeletons of marine life form a thick strata, which over millions of years, compresses and solidifies. Over time, this sediment cements together to become rock beds. As rainwater leaches through the soil, a mild solution of carbonic acid is released through cracks in the limestone, enlarging them. The drips also create other cave formations like stalactites. Over time, some passages erode to a large enough extent to become underground streams or rivers. As a result, a hidden world is created, a world of caves, sinkholes and complex shafts.

The three Abbey Caves formed over 30 million years ago. Organ cave is the largest of the caves where in the main Catacomb you will see the organ pipes. Be prepared to get wet up to your waist! Middle Cave and Ivy cave are smaller but equally interesting where it is possible to enter and exit at different points. In all the Caves you will see magnificent glow worms.

Caving Safety Tips

Getting lost deep underground or dangling from a cliff top with shabby equipment is no way to spend your holiday in New Zealand.

Some tips include:

• Never go caving or climbing alone.
• Make sure all equipment is reliable and in good condition. When caving, carry at least three sources of light - a headlamp, a torch (flashlight) and candles.
• Always Wear a safety helmet
• Never attempt independent climbing and caving without proper training and without first becoming familiar with the site.
• Climbing and caving require a moderate to high level of fitness - get in shape beforehand.

 

Glow Worms ARACHNOCAMPA LUMINOSA.

New Zealand caves, riverbanks and other shady crevices provide a home for New Zealand's most famous fly - the glow-worm. The life cycle of a glow-worm is about a year from larva to fly. During that period it casts the luminous glow for which it was named. The light is often an eerie green and is stronger when the worm is hungry. From the ceiling of a cave, the worm suspends lines of sticky beads to trap prey, which are attracted to the light. Once prey is caught, the glow-worm pulls in the line to feed. Looking at a ceiling of glow-worms is like gazing at the stars on a clear night. A mature adult glow-worm fly has to be careful not to get trapped in a glow-worm line itself, and be eaten!

What makes a glow worm glow?

The blue/green glow of the larvae is the result of a reaction between body products and oxygen in the enlarged tips of the larvae’s excretory tubes. The light is the result of a chemical reaction involving several components:
luciferin (a waste product) luciferase (the enzyme that acts upon luciferin) adenosine triphosphate (the energy molecule) and oxygen. All these combined make an electronically excited product capable of emitting a blue-green light.
 

Not really worms?

The name glow worms is a misnomer as they are larvae, not worms.
Early settlers from the British Isles probably applied the common name 'glow worm' as a substitute for the English glow worm Lampyris noctiluca (actually beetle larvae, so they got it wrong there also)The life cycle of a glow worm involves four stages: egg, larva, pupa and adult fly. Eggs are laid in large numbers directly onto the walls of the site.
Some two weeks later the eggs hatch into tiny larvae that immediately start glowing from their tails.

Glow worms are light sensitive so please don’t use the flash on your camera or shine your torch directly on the glow worms.