Rock Hounding and Glow Worms

Hokitika is known for its situation on the west coast very close to a very rich source of New Zealand greenstone (also known as New Zealand jade, also known as nephrite), properly known as pounamu. This type of gemstone is unique to New Zealand and tourists buy it by the ton in Hokitika and nearby Punakaiki. It’s a gorgeous dark green, much deeper than emerald, than has a slightly translucent quality. And even when found on the shoreline, its surface is smooth.

The Maori treasured it for centuries before Europeans even arrived in New Zealand. They would trek across the mountains of the central South Island from their settlements on the east side on quests for the green stone. Then they would use it as an edge for tools (its only match for hardness is diamond) and the material for jewelry. When Europeans arrived they took to the habit of collecting and selling the stuff. Now there’s a thriving industry of gem cutting and jewelry sales in the Westland. (They don’t use it for tools much; it turns out stainless steel is a good replacement for cutting and grinding implements.)

The river that has the greatest quantity of pounamu is just north of Hokitika. While white folks can visit there and go swimming, they can’t take any of the greenstone. Only Maori can do that. There are some places where the old treaties still hold.

But beaches are fair game. Something we discovered here in Hokitika is walking down the beach and admiring the vast variety of stones that splay across the shore. They are the size of a fist and smaller, ground smooth and round by the beating waves. There are pure white ones that look like quartz or soapstone; there are striated grey ones; there are reddish-brown stones that resemble beryl; there are light green stones with black flecks of iron oxide; there are jet black pebbles; and there are stones that mix and match every colour in streaks, specks, and stripes. It’s amazing to walk along on the edge of the lapping surf and take in the stunning array of colour and texture in these stones. It’s also fun to walk along and search for pounamu. We found a few that, while not pounamu proper, are a deep dark green that we don’t often seen in rocks back in the States. I restrained myself, and only took one. (A local artist and rock hound told me that it’s semi-nephrite; the stuff of pounamu, but not completely transformed to the gem by geologic processes.)

There’s also glow worms here in Hokitika and—bonus!—they don’t charge admission to see them! Glow worms are the larvae of a species of fly native to New Zealand. The short-lived flies lay their eggs in inaccessible locations: forested cliffs and cave walls and ceilings, especially. The first larvae in a field of eggs hatch and—here’s the Wild Kingdom part—consume their unhatched brothers and sisters in order to get their first dose of energy for life. After that, they have to hunt their own food.

They do this by exuding a string of mucus beads that hang down from wherever they are perched. Then, once the sticky substance is dangling and drifting in the breeze, they turn on the charm. When the sun goes down, these larvae emit a green glow from their behinds which attracts small flying insects like midges. When the flying insects get stuck on the mucus beads, the larvae eat them up. It’s a bug-eat-bug world, after all.

In order to see glow worms it’s gotta be dark. That means going for a trek at night (no flashlights, people) into a secluded patch of forest away from the edge of town. Yes, it sounds like the setup for a horror film. But this is New Zealand, so it’s OK. And the Department of Conservation has been so kind as to install handrails by which to walk so you don’t kill yourself in the jungle. They’re very hospitable here.

So we walk into this deep, dark dell, our eyes adjusting all the time to less and less light, and suddenly we’re surrounded by a galaxy of pale green stars. They’re on the walls next to us and high above us. The trees and ferns block out all ambient light from the sky, so really all you see are the insectoid constellations. Gorgeous! We took some photographs, but we’ll see how they turn out. The glow worms are so small that even at maximum zoom, all you see through the lens is a prick of green light.

Speaking of photographing glow worms, I’d like to make a public service announcement. If you’re ever at a glow worm dell—or any other natural wonder that requires viewing in the dark—please mind the hundred signs on your way in that instruct you not to turn on any lights. Not only does it perturb the worms, but it irritates photographers trying to operate in the low-light conditions. And it’s just plain rude to those whose eyes have adjusted to the darkness. It doesn’t bother me if you climb over the handrails above ocean cliffs; if you fall, you won’t take me with you. But spoiling the effect of a natural wonder for others around you—definitely off-limits. Please mind the signs. Cheers.

~ emrys