Blue Dragonflies

Of all the glittering insects that patrol our creeks and ponds, few are as eye-catching as the blue dragonflies. A flash of electric blue zipping across the water or a sapphire jewel resting on a reed is a classic sight of an Australian summer.

When you spot a bright blue dragonfly, you are almost certainly looking at a mature male. In the dragonfly world, the males are often the show-offs, using their brilliant colours to hold territories and attract a mate.

A Trick of the Light

The vibrant blues you see on these insects are rarely caused by pigment, like a paint or dye. Instead, the colour is often structural. It’s created by microscopic structures on their body that scatter light, reflecting only the blue wavelengths back to your eye.

In some species, the blue is actually a dusty, waxy coating called pruinescence that develops as the dragonfly matures.