Locals on Sydney's Northern Beaches flocked in droves to witness a spectacular natural phenomenon over the weekend, with dozens gleefully watching on from the shore at Manly as glittering bioluminescence transformed the surf into a sparkling sea of neon blue.
The incredible, natural display is a result of a chemical reaction within an organism's body — commonly seen in jellyfish, bacteria, squid and crustaceans — that produces a glowing light energy.
Certain conditions, ranging from an algae bloom of plankton to changes in the sea's temperature, create large amounts of bioluminescence, with the "glowing" look appearing when the ocean is disturbed by a wave breaking or splashes in the water at night.
Manly residents took to social media on Saturday night to post images of the dazzling display, with shots showing dozens of locals dotting the beach to admire the spectacle.
Bioluminescence also seen recently at Manly
It's not the first time the region was treated to the magical sight, with photographers capturing a similarly spectacular show along the same stretch in August.
Jervis Bay, on the NSW South Coast, is also an area well-known for hosting incredible bioluminescence.
Bioluminescence, sometimes referred to as “sea sparkle” thrives in still, warm sea conditions and often can go totally unnoticed until it concentrates on the surface and creates the sparkling effect.
On land, the stunning phenomenon is seen most notably in fireflies.
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