Professional fishers in the South Australian Marine Scalefish Fishery are worried amateur catches are rising and skewing efforts to protect stocks in the state.
In 2021, a major industry reform reduced the fishing fleet by a third to 200 licences in a buyback scheme.
Individual transferable quotas (ITQ) were also introduced on key species like whiting and calamari, to make the profession more viable and help protect fish stocks.
However, professionals say the reforms mean nothing if the catch of the recreational sector increases and is not accurately counted.
Marine Fishers Association chief executive Pat Tripodi said there were concerns about calamari and whiting stocks in localised areas, including Port Lincoln and Wallaroo.
"There are certain areas that we need to monitor closely and investigate why we are seeing lower numbers at the moment," he said.
Jarrod Day's grandfather also fished in the fishery. (ABC News: Jodie Hamilton)
Professional Port Lincoln and Yorke Peninsula fisher Jarrod Day said a lack of recreational data created uncertainty.
"Unfortunately, a lot of commercial fishermen believe that the King George whiting and the calamari are in just as bad a state as the snapper were before the shutdown of the snapper," Mr Day said.
"That's a real worry when we're not getting listened to."
"I just want to see it sustainable. I just want to see an even playing field."
The professionals record their exact catch details on an app while the recreational sector is managed by daily catch limits on different species.
There were 356,700 recreational fishers in South Australia, according to the South Australian Research and Development Institute's (SARDI) 2020/2021 telephone survey of 1,000 amateur fishers.
It was an increase of 23 per cent from the previous survey seven years earlier.
The Marine Scalefish Fishery is the biggest and oldest fishery in South Australia, established 188 years ago. (Supplied: State Library of South Australia and Jarrod Day)
The recreational sector caught 305 tonnes of whiting from March 2021 to February 2022.
Mr Tripodi said this figure did not include the catch by interstate visitors.
For the same period the commercial sector caught 168 tonnes.
More data needed
Professional fisher Hugh Bayly said the key to healthy fisheries was knowing the total biomass and total catch.
"They're [the phone surveys are] totally inadequate, they're not proper science at all and because of that SARDI have no idea of what the recreational catch is," Mr Bayly said.
He said a recreational fishing licence would provide accurate figures.
"With a recreational licence, attached to boats, boat fishermen, then at least they'd have a list of people that actually go fishing and hand in hand on that should be a mandatory phone app to report your catch when you come in," he said.
"That would give PIRSA [Department of Primary Industries and Regions South Australia] and SARDI more information than they've ever had."
South Australia and Queensland are the only states without some form of recreational fishing licence.
Graham Harrowfield is a third-generation fisherman. (ABC News: Jodie Hamilton)
Whyalla fisher Graham Harrowfield was frustrated there was no accurate count of the total number of fish taken from state waters.
"All we want is for PIRSA to sustainably manage the fishery and it's a requirement that they have the number of fish that each sector catches," he said.
"It's just been a guess by the scientists on what the figures are."
No new licences
The State government has previously ruled out a recreational fishing licence.
"The recreational fishing survey has been in place for many years and provides a good snapshot of where the recreational sector is at," Fisheries Minister Clare Scriven said.
"If there are other ways to improve that data I'm always happy to look at them."
Ms Scriven said the state's fishing resources were sustainable, with the exception of the snapper industry, which was under a six-year closure.
Shane Hodgens says recreational fishers should need a licence. (ABC News: Jodie Hamilton)
The state's leading recreational body RecFishSA is open to a fishing licence or permit system if money goes back into recreational infrastructure but is not supportive of mandatory reporting.
"There's a growing number of recreational fishermen now that do want to contribute, and they do want to a licence," RecFishSA board member Shane Hodgens said.
"The only way we can see much better management of the fish stocks is through a licence and raising more money for that management purpose."
Mr Tripodi said the reform brought hardship for many fishers.
The new ITQs have a fee per kilogram, before a fish is even caught, with some professionals now paying almost 400 per cent more in licence and quota fees.
The South Australian government has provided an interim subsidy for the quota fees to help during the transition period.
Mr Tripodi said the government's management structure also needed reform to reduce costs.
"We've got a lot of stressed people now that are very worried from stress financially about how they're going to be profitable into the future," he said.
"Some people are facing $20,000, $30,000, $40,000 bills, when previously the most expensive license fee was about $10,500."
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