There are several places in New Zealand to see glowworms – or rather, the beautiful lights they create on the walls and roof of the caves they live in. But how much do you know about the tiny little insect creating these amazing displays? Let’s find out more about glowworms in New Zealand.

What are glowworms?

Our glowworms are the larvae (grubs) of a species of gnat called Arachnocampa luminosa, which is unique to New Zealand.  Their scientific name means ‘spiderlike (arachno) ‘larva’ (campa) ‘that produce light’ (luminosa).

Glowworms spend most of their life as larvae and can grow to about the size of a matchstick. You’d probably be disappointed if you saw one without its light on, because it looks a lot like a maggot! It’s better just to enjoy the beautiful effect they create.

Why do glowworms glow?

The pretty light that you see when you visit Waitomo Caves comes from the glowworm’s tail. It’s bioluminescent, so the chemicals it secretes react with oxygen in the air and create light. This attracts the glowworm’s prey, which then gets trapped by the sticky threads the glowworm spins. This is why their scientific name includes ‘spiderlike’– because they catch their food like spiders do, just with an added light show!

What do glowworms eat?

Glowworms catch and eat small flying insects, like moths and flies.

Why do glowworms live in caves?

Caves are dark, damp and sheltered, creating an ideal environment for glowworms to live in. The darkness ensures the glowworms’ lights can be seen, and there’s no wind to dry out or blow away their sticky threads. They’re particularly attracted to the Waitomo Caves because it has an underground river flowing through it, which helps bring them plenty of insects to catch. 

Where to see glowworms in New Zealand

The most famous place to see glowworms in New Zealand is the Waitomo Caves. These caves in the central North Island have lots of the little critters living in them. Part of a Waitomo Caves tour includes a boat ride through a grotto filled with glowworms. The effect is spellbinding – it’s like gliding along underneath a beautiful blue galaxy.

You can also see glowworms in the Kawiti Caves in the Bay of Islands, in Te Anau and in the Waipu Caves in Northland.

Why can’t I take pictures in the Waitomo Caves?

The conditions inside the Waitomo Glowworm Caves are carefully monitored to make sure the glowworms are being looked after. Flash photography isn’t good for the insects, so no photos are allowed inside the caves. Luckily the spellbinding sight of a twinkling galaxy of lights overhead is so unforgettable, you’ll remember it without any pictures!