In a stunning display of marine underachievement, a dive survey off the coast of Whyalla, South Australia, has counted only 44 giant Australian cuttlefish, prompting fears of a 'catastrophic' decline. Scientists and divers are now demanding the state government release official population estimates, presumably so they can officially panic.

Each year, tens to hundreds of thousands of these cephalopods gather in the upper Spencer Gulf for a breeding bonanza - the only place on Earth where cuttlefish throw such massive parties. Historical surveys since 1998 show populations ranging from a low of 13,500 in 2013 to a high of 247,000 in 2020, with over 63,000 recorded in 2025. This year, however, the numbers are expected to be the lowest on record, thanks to the devastating effects of a toxic algal bloom that has turned the local marine environment into a bit of a downer.

The intrepid team of four divers from ecological not-for-profit Eyrelab, who braved the waters in July, also counted only 440 eggs where millions would typically be. 'This is by far the lowest abundance that we've had on record,' said Manny Katz, diver and Eyrelab director, adding that the few dozen cuttlefish they saw were 'not out and about - they're hiding.'

Stefan Andrews, a marine biologist from the Great Southern Reef Foundation, is calling for the state government to release the official figures. 'It's clear that it's going to be bad news,' he said. 'People need to know just how bad the situation is. Let's see it, and not sit on it too long because the clock is actually ticking.'

The historically low numbers have already led tourism and dive operators in Whyalla to cancel their cuttlefish season in June. On 1 July, the state government introduced temporary restrictions on recreational activities like swimming and snorkelling, to give the breeding cuttlefish some peace and quiet and protect their eggs and hatchlings.

At a press conference on 30 June, Prof Mike Steer, the SA Research and Development Institute's executive director, said 'less than 50 animals' had been observed earlier in the season, but those were 'raw counts' requiring further monitoring and analysis before a population estimate could be provided. A state government spokesperson said surveys have now been completed, and 2026 estimates will be released after review. They noted that 'cuttlefish numbers naturally rise and fall from year to year' and that while the algal bloom likely impacted numbers, researchers are working to determine if it's the culprit.

Assoc Prof Zoe Doubleday, a cuttlefish and octopus expert at Adelaide University, suggested the bloom may have killed cuttlefish directly or altered the availability of their food supply - or their predators' food supply. Cuttlefish live short lives and adults usually die after breeding, making the population heavily dependent on the success of each breeding season.

Australia's first bloom of toxic Karenia cristata algae, which began in March last year, is still present along parts of the South Australian coastline. It's the largest and most destructive algal bloom in the nation's history. Latest testing shows elevated levels of Karenia algae at seven of 32 sites on the Eyre peninsula, and two of 19 sites on the Yorke peninsula.

Andrews said the federal government should also consider listing the species as threatened under the Environment Protection and Biodiversity Conservation Act, given the 'catastrophic decline.' While giant cuttlefish are found along the Australian coast, the animals in the upper Spencer Gulf are genetically distinct. They also display unique behaviours, like female mimicry - 'males pretending to be female, to get up close to the other females so then they can sneak mate with them.' Because nothing says desperate like wearing a disguise to get a date.