Algal Bloom Update

7 July 2025


Algal Bloom Update


Clean Seas Seafood Limited (“Clean Seas” or “the Company”) (ASX: CSS, OSE: CSS), refers to recent extensive media coverage of the significant harmful algae bloom (“HAB”) of the species karenia mikimotoi which has been ongoing for some months in the waters of South Australia, and which has been affecting marine life across the region.

On Friday, 4 July 2025, Clean Seas detected the presence of karenia mikimotoi in the Company’s Arno Bay hatchery for the first time which coincided with elevated mortalities of fish contained in the hatchery.

The Arno Bay hatchery currently holds both Kingfish broodstock and the first of four planned intakes of Clean Seas’ Year Class 26. At this stage, mortalities have been most concentrated among the smallest fingerlings, while the broodstock appear to be less impacted.

Clean Seas has long-established contingency plans in place, including additional broodstock held in sea cages in Port Lincoln. The Company also retains the operational flexibility to increase both the size and number of future Year Class 26 intakes to ensure ongoing stocking levels and, ultimately, harvest numbers.

At this stage the Board of Clean Seas are of the view that with the current number of viable fingerlings in the hatchery and the contingency plans in place, there will be no material reduction in future harvests or sales. Accordingly, there is no change to the Company’s previously provided guidance.

Authorised for release by the Board of Clean Seas Seafood Limited.

For further information on Clean Seas Seafood, please contact:
Rob Gratton
CEO
rob.gratton@cleanseas.com.au
+61 434 148 979