At least 1 million salmon died at Tasmanian fish farms and were dumped at landfill sites and rendering plants in February in what authorities and the industry described as an “unprecedented” mass death triggered by a bacterium outbreak.
The revelation that waste facilities in Tasmania’s south received more than 5,500 tonnes of dead salmon last month – equivalent to about 1.07 million full-grown Atlantic salmon, or 8% of total annual production in the state – followed weeks of reports of fatty chunks of fish washing up on beaches in the Huon Valley and on Bruny Island.
The figures do not include the number of salmon that died from the outbreak in earlier months.
Fresh questions about the treatment of salmon were raised on Thursday when environment organisation the Bob Brown Foundation released drone footage from above a salmon farm appearing to show workers pumping writhing live salmon into a tub carrying dead salmon and then sealing it. It sparked accusations of cruelty and calls for the RSPCA to stop certifying Huon Aquaculture.
On Saturday the RSPCA said in a statement it had suspended certification for 14 days while it investigated further, saying the “inhumane handling of live, sick or injured fish as shown in the video being circulated is completely unacceptable”.
The acting chief executive of the state Environment Protection Authority (EPA), Cindy Ong, told ABC radio the mass mortality was “the largest event we have ever seen” and “not quite past the peak yet”.
“It’s correct to say it’s unprecedented,” she said. “We expect that it will be ongoing for a little while yet, but how long? I don’t know.”
Authorities said the deaths were primarily caused by an endemic bacterium, Piscirickettsia salmonis, that had been found in Tasmania’s east and south-eastern coastal waters since at least 2021. They said the death rate was exacerbated by warm summer water temperatures.
Ong said fish deaths were “a known aspect of salmon farming worldwide”. She said the EPA was investigating how what she described as “congealed fish oil” had washed up on shorelines, starting with a beach at Verona Sands in the Huon Valley on 16 February.
Conservationists said the deaths at farms operated by Huon Aquaculture and Tassal showed that the state’s salmon farming industry was “an animal welfare nightmare”. It follows previous criticism from scientists and activists about the industry’s impact on the environment and particularly the endangered Maugean skate in Macquarie Harbour on the state’s west coast.
The Bob Brown Foundation campaigner Alistair Allan said the latest drone footage taken at a Huon Aquaculture farm in the D’Entrecasteaux Channel, south of Hobart, that appeared to show live fish being placed and sealed in a dry tub with dead fish meant the RSPCA had “no choice but to drop their certification of this toxic and cruel industry”.
“This is the reality of factory-farmed salmon. Our waterways and beaches are covered with rotting chunks of diseased salmon, the Maugean skate has been pushed to the edge of extinction, reefs and sea floors are covered in sludge and slime, and communities are completely fed up with the corporate takeover of their waters,” he said.
The Neighbours of Fish Farming campaigner Jess Coughlan said: “Live animals suffering from disease that are left to suffocate to death absolutely should not earn the RSPCA badge that is displayed inshore alongside Huon Aquaculture farmed salmon.”
In its statement announcing the 14-day suspension of certification, the RSPCA said: “As the public response to this incident shows, animal welfare in farming is incredibly important to Australians, and this is no different when it comes to aquaculture. Fish are sentient animals capable of pain and suffering, which is why the RSPCA Approved Standard exists in the first place.”
Huon Aquaculture said it had launched a “full investigation” into the video footage, that it was “extremely disappointed” and that the actions shown did not represent “standard operating procedures”.
The chief executive of industry group Salmon Tasmania, Luke Martin, said the mass mortality event was an “unprecedented, first-of-its-size” event, and the EPA had confirmed the bacterium was of no risk to Tasmanians or the environment.
“It’s been a concerning time for our surrounding communities and we apologise for the impact and want to assure everyone that we are doing everything to fix this and make changes for the future,” he said.
The deaths this summer follow more than 1,000 tonnes of salmon dying in fish farms in Macquarie Harbour over seven months in the 2023-24 spring and summer. Aquaculture companies are required to report to the EPA when more than 0.25% of fish in a cage die on three or more days in a row. Dead fish are often rendered for use in pet food, fish oil and agricultural fertiliser. The industry says dumping in landfill is used as a last resort.
The Tasmanian premier, Jeremy Rockliff, this week told parliament that the deaths were “very concerning” and he expected the industry to be transparent with the community.
Interviewed on the ABC, Ong said site inspections of facilities receiving dead salmon had found some were not complying with the law and were likely to face “enforcement action”. She refused to name the facilities that had received fish carcasses or faced potential penalties.
The Greens MP Vica Bayley accused the EPA of “keeping Tasmanians in the dark”. “The EPA continues to withhold information from the public,” he said. “They need to stop with the secrecy and be upfront with Tasmanians.”
The deaths in the south of the state come amid a political fight over the future of the salmon industry in Macquarie Harbour. The harbour is the only known home of the Maugean skate, a ray-like species that has been affected by water deoxygenation caused by fish farm expansion.
The prime minister, Anthony Albanese, last month wrote to salmon companies promising Labor would legislate to guarantee “sustainable salmon farming” could continue in the harbour despite an ongoing legal review of a 2012 decision allowing the industry to expand. Albanese’s intervention followed the release of a new scientific report suggesting the skate’s plight had slightly improved after crashing last decade.
The independent Tasmanian senator Jacqui Lambie this week said she supported salmon farming but called for it to stop in the harbour.
