Fears of ‘catastrophic’ decline of giant Australian cuttlefish after only 44 counted in dive survey

Each year, tens to hundreds of thousands of giant Australian cuttlefish assemble off the coast of Whyalla, in the upper Spencer Gulf, to breed – the only place globally where cuttlefish gather en masse.

In surveys dating back to 1998, populations ranged from a low of 13,500 in 2013 to a high of 247,000 in 2020. More than 63,000 were recorded in 2025.