The latest scientific survey of cuttlefish numbers at Point Lowly has recorded a record high population size of over 240,000.
The annual survey was conducted by the South Australian Research Development Institute (SARDI) in June to coincide with the peak of the cuttlefish season.
The current population sized is estimated to be 247,146.
It comes after the state government announced a lifting of the ban on fishing cuttlefish in the Upper Spencer Gulf, a move which has drawn criticism from the community.
Many have called for the Marshall Government to reverse the decision, including $100m Whyalla Foreshore Hotel developer Barrie Harrop, who says the breeding ground for the cuttlefish at Stony Point should be heritage-listed.
But Primary Industries Minister David Basham says the latest survey results backed the state government's actions.
"This is fantastic news and a welcome reflection of how our government has used the best available scientific information to inform our decisions to ensure healthy fish stocks and benefit all South Australians," he said.
Minister Basham said continued population growth of the Great Australian Cuttlefish since the lifting of the fishing ban proved there were no longer sustainability concerns for the cuttlefish.
"This is wonderful news and should be celebrated by all South Australians and in particular the local Whyalla tourism industry who can expect to have another big year in 2021," he said.
"We have population data now which should give everyone confidence that this species has rebounded back to healthy levels."
However Shadow Primary Industries Minister Eddie Hughes isn't convinced, saying it's still too risky to allow the fishing of cuttlefish.
"The logic that's being used is that the protection has worked, now let's reduce the protection," he said.
"It's like saying whale numbers have gone up, let's now start hunting whales again. This is the only place in the world where this type of breeding aggregation occurs, so it's not a normal fisheries issue.
"We should be doing all that we can to protect the cuttlefish population in the Northern Spencer Gulf."