Why do glow worms glow?

Uncover the science behind the magical glow worms.

Most people may squirm at the thought of the creepy crawlies of Australia, but one small worm has climbed up the charts in the country’s popular animals. This is all due to its ability to glow in the dark.

Imagine you are deep within the Springbrook National Park, trekking through the lush greenery as the sun sets behind you. You arrive at the arched caves, stepping into their shadowy entrance until you are completely immersed in darkness. Except you realise, you have not been swallowed up by the dark. There is light dotted across the ceilings of the caves, almost like stars in the sky. These blue lights illuminate the rocky walls, creating an enchanting spectacle for all to see.

These are in fact, not man-made lights, but completely natural lights made by the famous Glow Worms. Thousands of travellers visit these caves yearly, watching in fascination at this enchanting display of nature. But how do these small creatures create this mesmerising glow?

About the Glow Worms  

Despite the name, glow worms are in fact not worms at all. They are the larvae of a primitive fly called the fungus gnat. The larvae, which are similar in size to a caterpillar, spend nine months within these caves. They feed and transform until they eventually become adults, resembling a large mosquito in appearance. The larvae stage is actually a lot longer than their adult period, which only lasts a couple of days before they perish.

The Science

Its natural blue/green light that has made these worms famous is all due to a chemical reaction. It occurs all inside the creature’s bodies, with a waste product, an enzyme, an energy molecule and oxygen. All of these products react together to create this natural glow. When you’re seeing the glow, it’s actually coming from the tail of the larvae.

The Reason They Glow

These glow worms don’t light up just for our amusement, but instead, have a completely justifiable reason why they produce the glow. Basically, it is all for food!

They use the light as a way to draw in prey, similar to a bug light zapper. The bugs become spellbound, slowly drifting closer and closer until they are caught in the worm’s web. These webs differ from a spider. A glow worm’s web is a long silk thread that hangs from the ceiling of the cave, comparable to a long dangling drool. The sticky residue on the silk thread traps the insects, leaving them hanging there as the worm drags up the thread to devour their prey.

How to see the glow worms

If you are travelling around the tropic lands of Australia, you can easily see these creatures within their natural habitat. A great place to spot these creatures is nestled deep within one of the World Heritage Listed National Parks named the Springbrook Park.

A simple drive from the Gold Coast can have you instantly within the lush greenery of the rainforest. You’ll find yourself surrounded by ancient trees and unique wildlife. Immerse yourself in nature, walking deep within the forest until you reach the arched caves of the national park. These dark and dreary caves come to life after sunset, with the ceilings sprinkled with blue lights, similar to stars in the sky.

Join a glow worm tour

One of the best ways to experience this phenomena is with an evening glow worm tour. You’ll be venturing into the forest at nighttime, but you’ll be in the hands of an experienced guide!

The evening begins as you head to Mount Tamborine National Park and enjoy a tasty evening tea along the way. We will then embark on a leisurely stroll through the rainforest, making our way to the glow worms. During the rainforest walk, you’ll learn all about the precious ecosystem. Make sure to keep an eye out for any nocturnal animals that may come out of hiding while you’re on your stroll.

The stroll will end at Curtis Falls. This majestic waterfall is located near the glow worms. Once your guide leads you to the glow worms, you’ll be amazed as they light up the caves like a starry night sky!

Related article: Things to do on the Gold Coast when it’s raining

Cameron Ward

Managing Director at Sightseeing Tours Australia

Cameron Ward turned his travel passion into a thriving Australian tourism business. Before he co-founded his own business, Sightseeing Tours Australia, he was enjoying being a Melbourne tour guide. Even now, Cameron delights in helping visitors from all around the world get the most out of their incredible Australian trip. You’ll see Cameron leading tours or writing about his favourite Australian places where he shares his local insights.