New Zealand has been the backdrop for many a movie and TV show thanks to its epic landscape. Among snowcapped mountains, deep lakes, and stunning Pacific beaches lie even more breathtaking spectacles if you just look a little deep... literally deeper, as in underground. The Waitomo Caves are known for their intricate rock formations and natural caverns but these caves hold another secret: glowworms.
With so much to see on the surface of the earth, it's not surprising that these caves go unbeknownst to many who visit this beautiful country. Even so, it's a popular attraction for the locals and anyone interested in plant biology and geology, especially when there's so much to know, learn, and love about these natural wonders. In the dark space of each cavern, these insects glow nearly as bright as the stars above each emitting their own luminosity in an unexpected and beautiful way. The science behind why these worms glow and why they've made the cave systems their homes is fairly simple, but still quite fascinating.
There Are Hundreds Of Caves But Those In Waitomo Are Free
Throughout New Zealand, there are hundreds of caves and many of them are home to glowworms and other insects that are adept to live in damp, humid conditions such as those in caves.
However, in Waitomo, there are places you can visit for free! For a more in-depth look at the inside of one of ten caves that are open to the public for tours, visitors can opt to pay for them, and this will take people through a select cave system so they can see the glowing worms - and the cave formatoins - up close. For anyone seeking a more casual, free way to see the same glowworms is to head down to Ruakuri Bushwalk at night with a flashlight. Visitors should be able to see them right from the trail!
Despite The Name, Glowworms Aren't Exactly 'Worms'... Yet
Glowworms are a cuter way to refer to these small, glowing creatures, however, according to biology, they're not actually worms yet. The long strands of 'worms' that visitors can see when touring the Waitomo Caves are actually in the larvae stage, making them closer related to maggots rather than fully-grown adults. As adults, these worms become gnats and go by the scientific name of Arachnocampa Luminosa. This doesn't make them any less admirable, though, as walking through an entire cave cavern full of these is quite an otherworldly and beautiful experience.
The Caves Themselves Are Millions Of Years Old
Most caves around the world span back centuries if not thousands of years and the caves in Waitomo actually span back 30 million years, to be exact. The process of how the caves and the sedimentary rock were formed is really quite incredible, as the base of this rock started with fossilized remains of marine life.
The tectonic plates that shifted underneath New Zealand brought the sedimentary rock up from below and as the exposed earth was subjected to various weather patterns, eventually cracks in the sedimentary ground formed, creating the cave systems.
Why Are The Glowworms So Luminescent?
There's actually a very good reason as to why these worms glow so brightly and it's not just so that they look pretty. Their glow is actually a signal to other worms during mating season and, similar to how a bird might sing to attract others or a flower attracts bees with pollen, glowworms attract mates with their light.
The process of glowing happens when chemicals in the tails of the worms come into contact with oxygen and the result is quite natural and predictable. When a mate is nearby, it's the long, sticky strand these glowworms hang down on that essential lures in and traps another worm.
No Photos Are Permitted In The Caves
While it might be tempting to try and catch this glow in action, there are no photos permitted in the Waitomo Caves or anywhere there might be glowworms. It's almost an instinct nowadays to reach for our phones or cameras to immortalize a memory on film but this must be respected, as the flash from a phone or camera can be incredibly harmful to both insects and the interior of the caverns.
The quality of life for these glowworms is so well-looked-after that even the cave conditions are monitored to ensure that the species is thriving. Additionally, the cave walls and the rock formations should be left alone; the environment within the cave is so sensitive that even one touch from a human hand can alter its natural chemistry.