South Australia’s recent environmental emergency—marked by widespread marine life deaths and over 100 people reporting flu-like symptoms after visiting the beach—has been linked to a toxic algal bloom caused by Karenia mikimotoi. This microalga, while usually harmless in low concentrations, can explode in number under certain conditions, such as warming ocean temperatures and nutrient runoff. These blooms are known to clog fish gills, reduce oxygen levels in the water, and release irritants that can cause respiratory and skin issues in humans. Although the toxins dissipate after the bloom subsides, the incident has exposed significant gaps in understanding how such harmful blooms arise and their potential links to climate change. Scientists are calling for further research and monitoring, as such events could become more frequent, threatening both marine biodiversity and public health.

Full The Conversation article by Professor Shauna Murray and Dr Greta Gaiani can be found here: https://theconversation.com/mystery-solved-our-tests-reveal-the-tiny-algae-killing-fish-and-harming-surfers-on-sa-beaches-252810