Whyalla wipeout fears: cuttlefish usually gather in their thousands, but few have appeared since a massive algal bloom (opens original article in a new tab)

Giant Australian cuttlefish populations in Whyalla have dropped dramatically this year, with only a few dozen observed instead of the usual thousands, likely due to a prolonged toxic algal bloom that began in 2022. Elevated levels of the toxic algae Karenia cristata were found in multiple locations, raising concerns about the health of the cuttlefish population and the impact on local tourism and the ecosystem.

• Giant Australian cuttlefish numbers are drastically lower than usual in Whyalla, South Australia, with only a few dozen observed instead of thousands
• A massive algal bloom of toxic Karenia cristata, ongoing since March 2022, is suspected as the cause of the cuttlefish decline
• Elevated levels of Karenia algae were found at 8 out of 32 testing sites, with concentrations up to 432,899 cells-per-litre in some areas