Beachgoers in Melbourne have been treated to a rare natural phenomenon as bioluminescent algae turned the waters off St Kilda beach an electric blue this week. The spectacle, caused by the algae noctiluca scintillans, was first spotted on Sunday by marine biologist Richard Pensak of local environment group Earthcare St Kilda.
Pensak described the sight as a 'bucket list' experience, noting that the algae, also known as 'sea sparkles' or 'red tide', can be irritating to fish due to high ammonia levels and reduced oxygen. He acknowledged that the algae's expanded range is linked to rising ocean temperatures.
Local author and illustrator Ryan Abramowitz visited the beach on Monday evening and described the experience as 'awe-inspiring' and 'cosmic and magical'. He said the iridescent blue rippling on the water's surface looked like 'shimmering galaxies whirling and swirling across the shore'. Abramowitz had seen bioluminescent algae before in Sydney and Bali, but never in Melbourne.
First documented in Sydney Harbour in 1860, the phenomenon has become more common in Australian waters since the 1990s, particularly in Sydney and Tasmania. Professor Shauna Murray, an algae expert at the University of Technology Sydney, explained that the algae contains proteins called luciferase that enable it to glow at night, and that warming waters due to the east Australian current have expanded its range southward.
