The discovery of a mysterious foam on a South Australian beach has led to over 100 surfers becoming ill and the deaths of numerous marine life, including leafy seadragons, fish, and octopuses. Health authorities have closed Waitpinga and Parsons Beach, approximately 80 kilometers south of Adelaide, attributing the foam to a microalgal bloom caused by hot temperatures, still water, and an ongoing marine heatwave. Surfers in the area have reported symptoms of blurred vision, itchy eyes, and respiratory difficulties. Local surfer Anthony Rowland shared images online of dead sea creatures washed up on the beach, including seadragons, indicating anomalies in the water. The foam has formed colorful lines in the sand and some bubbles exhibit a rainbow effect. After encountering the water, Rowland experienced a respiratory reaction. The reaction to his post was overwhelming, as multiple individuals came forward claiming similar illnesses. Furthermore, there are concerns the issue is spreading to other beaches on the Fleurieu Peninsula, with dead fish and octopuses being found in nearby Victor Harbor, Middleton, and Encounter Bay. The state environment department has confirmed the closure of the beaches for safety reasons, while the Environment Protection Authority is investigating the incident. The Epa has taken note of dead fish, seahorses, red staining, and foam on the beaches. Samples of water will be collected to determine the cause of the unusual phenomenon. It is believed that hot temperatures and a marine heatwave have contributed to the microalgal bloom. South Australia is currently experiencing drought conditions and has experienced extreme heat in recent times.

Source: https://www.theguardian.com/australia-news/2025/mar/18/mysterious-sea-foam-on-south-australian-beaches-reportedly-leaves-more-than-100-surfers-ill