This gentle New Zealand pastime requires nothing more than a torch and a sense of adventure.
None of the world’s glowworms are actually worms. Mostly they are beetles – there’s roughly 3,000 species of bioluminescent beetles, with the majority being firefly beetles. One notable exception is Arachnocampa luminosa, found only in New Zealand and Australia. These glowworms are the larvae of a species of fly known as a fungus gnat.
Unlike most fungus gnats, arachnocampa luminosa are carnivorous. They congregate in dark, damp spots like caves and forests, where they dangle strands of sticky mucus to trap small insects attracted to the light emitted from their abdomen.
This bioluminescent light is produced through a chemical reaction between an enzyme and oxygen, emitting a blue-green glow. Remarkably, this process is very energy efficient, with 90% of the energy used in the reaction converted to light. Compare this to the latest LED lightbulbs, which convert only 20% of their energy to light.
Cave-dwelling glowworms emit light at any time of the day or night, while outdoor glowworms start glowing shortly after dark and usually shine all night.
When a glowworm is disturbed, its light often disappears as the larva slithers into a crevice to hide its glow. To approach glowworms, be quiet and turn off your torch.
Glowworms can be found throughout New Zealand, but the best way to see them is on a guided tour. Many glowworm habitats are only accessible through these tours, which are led by knowledgeable guides who offer insights into the biology and behaviour of these fascinating creatures.
