Australia usually hosts the world's biggest cuttlefish mating event - not this year

Every winter, South Australia's Cuttlefish Coast is the site of the world's largest mating event for giant cuttlefish. However, this year's turnout was the lowest on record, prompting concerns about a catastrophic decline in the species. Official estimates indicate that only 1,811 cuttlefish arrived to mate this year, a 97% drop from last year's 63,000.

The state government attributes this decline to a toxic algal bloom that has affected the coastline for over 18 months. With adult cuttlefish only living for 12 to 18 months and the success of each breeding season determining the population's future, the sharp decline is alarming. During a recent dive survey, only 440 eggs were found along a five-mile stretch of coastline, whereas millions of eggs usually appear.

Divers noted that the remaining adult cuttlefish were acting skittish and hiding under rocks due to the scarcity of their peers. This year's mating season was impacted by the algal bloom, which has severely affected marine habitats. Stefan Andrews, co-founder of the Great Southern Reef Foundation, is advocating for the giant Australian cuttlefish to be listed as endangered due to the catastrophic decline.

Researchers are still investigating whether the algal bloom directly contributed to the population decline, but there are positive signs that the population may recover in the coming years if conditions improve.