Honeymoon Day 6 - Glowworm Caves

After a lovely breakfast at the B&B of museli, farm fresh eggs, bacon, etc. we hit the road towards Waitomo, where we had three cave tours lined up, including a famous gloworm cave. Unfortunately, we slightly underestimated the NZ roads and construction and arrived a few minutes late for our first tour. The thing about NZ roads is that they are almost universally windy, two lanes, and without many passing zones. So even if you wanted to zoom along like a crazy person on the windy roads, if you get stuck behind someone slow, you are out of luck for a while at least. Luckily the company was flexible and re-booked us on the tours, so they lined up okay. We had a little time to wait around though, so we had a picnic lunch and Charlie busted out the yo-yo for a while.



The first cave we toured was the Ruakuri cave. This is the only wheelchair accessible cave in the Southern Hemisphere (NZ sure does have a lot of the largest, smallest, only things in the Southern Hemisphere...). It starts with a really impressive spiral ramp leading down into the cave. The name of this cave is related to wild dogs, because the cave was discovered thanks to wild dogs making its entrance their home. The indigenous Maori people used part of the cave as a burial site a few hundred years ago, so that portion has since been closed off due to it being a sacred place.



Once we made it down into the cave level, and our eyes adjusted to the dim light, we embarked on our tour through a series of mostly natural but some man-made tunnels. They have done a nice job with ramps and walkways to make it easier to navigate and also to protect the delicate natural structures of the caves. We learned all about stalactites (from the top) and stalagmites (from the bottom), and how they are formed when calcium suspended in groundwater seeping in from rain re-crystallizes at the point the water exits the ground in the cave. There were some really impressive structures, which you can more clearly see in the later pictures in this post.



The main attraction for these caves were the glowworms. There were no pictures allowed in the big glowworm cave, so I tried to snag a couple in this first cave. The picture above shows the strands of web-like material that the worms drop to catch their prey.  The glowworms are the larval stage of a fly, and they attach themselves to the ceiling of caves, or sometimes to the dirt beside streams and such. Anywhere it gets dark with water that breeds other small insects, the glowworms might make their home. According to our guides, when insects hatch on the water, they look for light to fly towards to make their way out of caves. Because the glowworms look like stars, the insects get confused and fly right into their traps.



The glowing material is actually the glowworm poop.  The light it produces is continuous steady, unlike the blinking of the firefly, for example.

Being the super nerd that I am, I had to wonder if it would be possible to cultivate glowworms and harvest the bio-luminescent material from them in a non-lethal way. Currently fireflies have to be crushed and jellyfish cut apart. They are such a pretty blue, wonder what wavelength that is...



The caves were full of delicate rock structures like these. Back when the caves first opened and conservation wasn't quite as important, people used to break them off to keep as souvenirs, which is obviously not cool, particularly since they regenerate very, very slowly. In a year of growth, you might see the thickness of a fingernail added to the structure!



There are miles of these caves underneath the hills in the Waitomo area, but the three that we visited are the most popular currently, and certainly very well maintained and set up for tours. The tour company we went with also runs more intense caving tours, that include abseiling, climbing, and tubing on the river that runs through the largest cave. We even saw them way down in the cave at one point in our tour. I was happy to be up in the dry part of the cave though, it was cold enough in there and even though they were wearing wet suits it seemed a little too intense for me.



There were some low ceilings and tight spots in the caves, as one might expect. Sometimes it's nice to be short! This is the entrance to the second cave we explored - The Aranui cave. This one was smaller than the other two, but had some really gorgeous structures. Our guide was a little quirky for this trip, and we spent a lot more time listening to him in the dark before he had one of the kids "hit the lights", but it was still pretty awesome.




The second cave was also home to some interesting insects. The long legged insect in this picture is a cave weta. They are big, about a hands width with the legs included, but are basically like crickets, so they won't hurt you. It was a little creepy to see the guide shine the light up at them in the crevices above our heads though, even though we knew they weren't about to jump down on us or anything.

The tour company has done a nice job adding lighting to show off the cave features. The lights are all on timers since leaving them on all the time would heat up the cave and potentially cause problems with the chemistry of the rock formations. There were a couple times when the timers weren't quite timed correctly with the group, which was a bit startling but also pretty cool. When they turn the lights off you get the idea of just how dark it is down there and can imagine what it must have been like being the first person to get into the cave, with just a headlamp to show them what it looked like.



We also learned that they carefully monitor the CO2 levels in the caves, and need to cancel a tour on occasion when the levels are too high.  This is to protect the stone, not the people- the limestone gets extremely soft and can essentially melt if the CO2 concentration is high enough.

The last cave we toured was the Glowworm cave, so named because of the amazing lights display at the end. The picture below isn't mine, because we weren't allowed to take pictures in there, but it's a good representation of what it looked like.

The first part of the tour was basically the same as the others, but the cave is much larger so that was kind of cool. Large enough that they hold concerts in the main hall of the cave sometimes to take advantage of the awesome acoustics. Then at the end, you are loaded into a boat and everyone is asked to be silent as the guide pulls along a series of ropes to float the boat through still waters underneath a galaxy of glowworms. It was really a unique sight, and I'm so glad we were able to get there while we were on our travels.



From the caves, we drove a few hours back to Auckland, and stayed in a hotel near the airport so we were ready for our flight to Christchurch on the south island the next day.