South Australia is currently experiencing a harmful algal bloom (HAB) of unprecedented scale, with impacts extending across ecosystems, industries, coastal communities, and Sea Country. The event is the largest recorded in South Australia and ranks among the most extensive and consequential HABs documented in Australian waters.
A coordinated, cross-government response—supported by universities, industry, national research organisations, and engagement with First Nations partners—has mobilised scientific capability at pace. Integrated observations from satellites, in situ monitoring, hydrodynamic modelling, and laboratory analyses have informed risk-based decision-making across fisheries, aquaculture, environmental management, and public health. Scientific delivery, led in large part by SARDI, has been central to this response, alongside Department for Environment and Water investigations into impacts on marine mammals, seabirds, and ecosystem health.
Drawing on leadership of the scientific response and public communication, key lessons are emerging in managing risk communication, maintaining public trust, and responding in a dynamic and complex environment. Focus is now turning to understanding drivers and improving preparedness and forecasting. The recently established Office of Algal Bloom Research will foster national collaboration and address critical knowledge gaps.