Massive algal bloom threatens South Australia's seafood exports

The bloom, about 6 times the size of Singapore, may have killed over 14,000 marine animals

- Jonathan Pearlman

SYDNEY - In April 2025, Mr Steve Bowley, an oyster farmer in a small fishing town in southern Australia, noticed that the waters around his oyster farm, which are typically pristine, had turned dirty brown.

He knew immediately what the problem was. A massive bloom of algae—it now covers 4,500 sq km, about six times the size of Singapore—had been spreading along the coast of South Australia state, and finally arrived in his home town of Stansbury.

Shortly after, state authorities advised Mr Bowley, whose Pacific Estate Oysters farm has more than 1.5 million oysters, that he could not sell his produce due to fears they could contain toxins.

Mr Bowley, 68, who is unable to sell his oysters for 82 days from July 25, told The Straits Times that he is considering giving up oyster farming and is looking for another job.

"It will be months before we open again—I am virtually bankrupt," he said from Stansbury on the Yorke Peninsula. The town is directly opposite Adelaide across the St Vincent Gulf.

"The sea here is sick. There is nothing alive under the water. It will take years to recover," added the oyster farmer of 19 years.

The spread of the algal bloom has not just ruined businesses such as Mr Bowley's, it is also affecting more than 450 species of marine life and threatening the region's exports of high-quality seafood.

So far, the algae are believed to have killed more than 14,000 animals off the coast of South Australia, including fish, dolphins, eels, sharks, rays and crabs. At beaches across the state, fish, octopuses and other marine life have washed ashore, while damage to seagrass and reefs poses a long-term threat to marine ecosystems.