Overview

• First detected off the Fleurieu Peninsula in March, the Karenia mikimotoi bloom has split into Spencer Gulf, Coorong wetlands and reached Gulf St Vincent shores
• Researchers link the rapid proliferation to a marine heatwave since September 2024 and flood-driven nutrient runoff
• Tens of thousands of fish, sharks, rays and other gill-breathing animals from nearly 400 species have died, prompting fears of local extinctions
• Local fishing communities report empty nets and growing economic distress as stocks vanish
• South Australia’s environment department is monitoring water quality while opposition parties push for federal aid under a declared national disaster