Lucky beachgoers were treated to a spectacular show last night, as the water in St Kilda Beach glimmered with bright blue flashes of light. According to Professor John Beardall from the School of Biological Sciences at Monash University, this stunning natural wonder was likely caused by a non-photosynthetic dinoflagellate alga, known as Noctiluca scintillans. You might know it by its more common and romantic name, ‘sea sparkle’. The light occurs when the organism is agitated, creating the neon glow. And last night, visitors in St Kilda got to see the bioluminescence first-hand, as the breaking waves transformed the dark waters into a glittering canvas.
Bioluminescence in St Kilda
Bioluminescence has been known to happen around Port Phillip Bay, including St Kilda, Hampton and Aspendale, as well as in coastal waters elsewhere, such as Jervis Bay in New South Wales.
“Bioluminescence is particularly noticeable when the populations of Noctiluca build up,” said Professor Beardall. In other words, they form a bloom. These blooms are triggered by a combination of factors, such as calm conditions, the right temperatures and even the level of salt. “Often they are associated with warmer weather and around river outlets after rain.”
And with the wet weather we experienced over the weekend, we’re not surprised to see bioluminescence in our neighbourhood.
The organisms are also quite buoyant, and a nice gentle breeze into the bay means that they get concentrated along the shore.
Finding bioluminescence in Melbourne
You can’t really predict when and where you’ll see bioluminescence around Melbourne. Sea sparkle can easily be disturbed by the wind or the tides, so just because it’s visible on one night does not mean that you will see it again the next night. Generally speaking, try to look out for it on a calm night after rain.
If you’re keen for updates or alerts, check out the Facebook group Bioluminescence Australia, which posts photos and helpful information. Then, once you know where to go, bring your camera along and feel free to walk through the water to see the glow. Just don’t swallow it or put it on your face or in your eyes.