Two Tasmanian commercial fishermen are using rod-and-reel fishing methods to catch sashimi-grade southern bluefin tuna to meet the demand of Japanese restaurants on the mainland.
Ash Garland and Aiden Jackson have started using the recreational fishing methods to bring in commercial quantities of the fish.
Catching southern bluefin tuna is limited by quota, so this duo have been targeting high quality, sashimi-grade fish to get the most value from what they are allowed to catch.
Commercial fishermen have often used longlines to fish tuna that are many kilometres long, with thousands of hooks, and little control over the size and quality of fish caught.
The premium quality fish sells for $30 a kilogram to restaurants in Sydney, Melbourne, and Hobart.
Mr Garland said they use rod and reel with a barbless lure that has allowed them to release the less valuable fish.
They said they have had to learn a lot about how to spot and care for top quality tuna.
"You look for fatness through the tail, a sort of cricket bat-like shape," Mr Garland said.
Out of the water, each fish must be managed "like a baby" to maintain the sashimi quality.
Mr Jackson said he must have every fish cleaned, wrapped, and on ice within three minutes of being caught.
"Every minute after we leave it, it goes up a degree inside and it ends up starting to cook the flesh," Mr Jackson said.
The pair go out for four days at a time and reel in up to a tonne of tuna by hand.
A recovering fishery
Sean Tracey of the Institute for Marine and Antarctic Studies said southern bluefin was overfished in the 1970s and 80s.
"We're now seeing a stock recovery."
The fishery was recently declared recovering.
Dr Tracey said a lot of recreational fishers new to catching bluefin did not know how to care for the meat properly.
"We've got a program at the moment called Tuna Champions, which is an initiative to get the recreational fishers thinking about what they do with the southern bluefin tuna that they catch," Dr Tracey said.
He used Mr Garland's operation as an example of how recreational fishers should treat their catch, in a documentary for Tuna Champions.
"They [Mr Garland and Mr Jackson] are handling each fish like an absolute baby from hook-up to unloading," Dr Tracey said.
"Making sure they're brain spiked so it's a humane killing, icing the fish down, making sure every fish is in its absolute best condition.
High-end demand
Mr Ishii taught the fishermen how to grade and look after the tuna to ensure they get the high price tag.
In Australia these fish sell for $30 a kilogram, but Mr Ishii said the same fish would sell for $50 a kilogram in Japan.
He had bought from the pair before, but came to Tasmania to check the fish were being cared for properly before sending some to Japan.
His main concern was that the rod-and-reel method could affect the quality of the sashimi, because fighting with the fish can release adrenaline into the muscles.
But Mr Garland said struggling with the fish for more than 20 minutes would allow the adrenaline to be reabsorbed, maintaining the quality.
"I just wanted to double-check the quality, but actually [the] tuna is quite good," Mr Ishii said.
Mr Garland said their product was already in high demand at the moment.
Executive sushi chef at Masuya Japanese restaurant in Sydney, Toshihiko Oe, also came to inspect the catch and said he could not get enough of this new product.
"I want to buy them all," Mr Oe said of Mr Garland's catch.
The fishery has only been operating for a few weeks, but Mr Garland said catching tuna like this had been a dream of his for a long time.
"We've had the opportunity to get this boat and we've got some quota and no-one is really doing it down here — the bluefin tuna, especially rod and reel — so we jumped at the opportunity," he said.