Environmentalists have given the green tick to just one brand of canned tuna as industry heavyweights threaten dwindling fishing populations and other marine life.
For the first time, the Australian Marine Conservation Society has evaluated the nation's most popular tuna brands and classed them as green, amber or red based on their sustainability credentials.
Safcol's No Net Tuna is the only fully green-ranked product, with the society ranking it a "better choice" than others.
Most products received amber rankings due to their use of purse seine nets.
Brands have largely stopped using fish aggregating devices (FADs), which are designed to cast a shadow in the water to attract fish with less effort.
The devices, which have a higher chance of entangling sharks and turtles, had been replaced by the purse seine devices, the society's sustainable seafood guide manager Adrian Meder said.
"While better than FAD, purse seine can impact endangered marine life such as manta rays," he said.
"There are still major issues in the tuna industry."
Safcol's No Net Tuna only uses fish taken by pole and line methods, while others were given mixed green/red ratings for their sourcing.
Sirena and Aldi's Ocean Rise tuna received mixed ratings because some of their tuna is sourced from healthy populations, but they also use yellowfin tuna from overfished stocks in the Indian Ocean.
Mr Meder said a number of brands only listed the fishing zones on the cans, meaning little to the consumer.
Cans with FAD57 or FAD51 stamped on top come from the overfished yellowfin tuna populations.
The Check Your Tuna guide was based on scientific evidence from international regulations and monitoring organisations, independent from government, fishing industry or retailer sources, the society said.
The organisation's imports lead, Kimberly Riskas, said labels on all seafood cans should include specific information about the species contained within, where it was caught and how.
"We were pleased to see that every canned tuna product we examined stated the species in the can, something conspicuously missing from a lot of the seafood sold in Australia," she said.
"We have a right to know what we're eating, but instead we're being left in the dark."
Dr Riskas said more needed to be done to address issues with other seafood sold in Australia, but the tuna industry was making a good start.
The organisation's 2025 Check Your Tuna criteria will incorporate an assessment of illegal fishing, including labour abuses on boats.
