By Sophie Holder

Topic: Marine Biology

Wednesday, 8 July 2026, 6:20 am

A bad algal bloom hurt South Australia's coastline and killed many marine animals.

In short:

A type of algae in the bloom is the most toxic of its kind that has been studied.

The algae, called Karenia cristata, was found to make brevetoxins in November 2025.

What's next?

The algae could bloom anywhere with similar water conditions.

The algae that made brevetoxins in South Australia's algal bloom is very toxic.

An Australian team studied the algae and found it was very toxic, even in small amounts.

The team tested the algae in a lab and found it was very harmful to marine animals.

The algal bloom was first seen in March 2025 in South Australia's Fleurieu Peninsula.

'Potent' algae

A researcher, Craig Styan, said the algae was very toxic, even in small amounts.

He said a small amount of the algae could have a big effect on marine animals.

Dr Styan said the testing helped them understand why the bloom was so bad.

He said the algae was very harmful to marine animals, even in small amounts.

Brevetoxins were found in foam on beaches in August 2025.

Dr Styan tested the algae on small animals and found they were very sensitive to it.

He said the algae was very harmful, even in small amounts.

That's much higher than the amounts they tested in the lab.

More research to do

The algae, Karenia cristata, had not been seen in Australian waters before.

Dr Styan said it would be bad if the algae appeared elsewhere.

He said there was still a lot to learn about the algae and its toxins.

The researchers want to understand what makes the algae produce toxins.

The researchers say they need to do more to stop similar bad events from happening.

A spokesperson for the SA Department of Primary Industries and Regions said the new findings would help future research.

The spokesperson said the findings did not change current public health advice.

Wednesday, 8 July 2026, 6:20 am

Wednesday, 8 July 2026, 8:27 am

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