Between September 2023 and March 2024, over a 7 month period, Tasmania’s Macquarie Harbour experienced a significant salmon mortality event, with approximately 1.15 million kilograms of dead salmon removed from the waters. This equates to roughly 10% of the farmed salmon stock in the area during that period.
The EPA data released this week confirms that 10 million kilograms of salmon have died in the 2 months of February and March 2025.
This is an estimated 2.5 million dead salmon.
This equates to roughly 13% of the entire annual statewide production of Atlantic salmon.
In early 2025, the salmon industry faced a bacterial outbreak of Piscirickettsia salmonis in southern Tasmania, where over 5,500 tonnes of dead salmon were dumped at waste facilities in February alone. This mass mortality event was also attributed to the warmer summer waters and it also followed an influx of salps and jellyfish. The March data has been recorded at 3,395 tonnes, with some onlookers suggesting this is understated with increasing suspicions around the possible dumping of morts (dead fish) into the waterways.
These events have intensified debates over the sustainability and environmental impact of salmon farming in Tasmania. Calls for greater transparency, stricter regulations, and even the relocation or reduction of fish farms have been voiced by environmentalists, some political figures and everyday members of communities around this state.
Media Statements below.
Media Release —Rosalie Woodruff MP, Tasmanian Greens, 6 May 2025
Ten Million Kilograms of Salmon Dead In Just Two Months
Horrific figures released by the EPA has confirmed what we all feared – in just two months, ten million kilograms of industrial farmed salmon have died from an insidious disease.
At least thirteen percent of the entire annual statewide production of the Atlantic salmon industry has suffocated and starved in sea cages in our once-pristine bays and estuaries, in just two months. That figure doesn’t include the fatty and fleshy remains of fish that washed up on our shores, ruining the summer for southern Tasmanians.
Ten million kilograms of dead fish equates to around 2.5 million mature Atlantic salmon that have suffered a cruel death at the hands of Huon Aquaculture and Tassal – an animal welfare catastrophe.
However, the EPA can’t or won’t provide an accurate breakdown of which leases these deaths occurred within, or even which region of Tasmania they occurred in.
The unchecked outbreak of disease throughout Tasmania is a biosecurity disaster of unprecedented scale in modern history. The Rockliff government has failed to explain how the disease has become endemic throughout Tasmanian waters – the only conclusion that can be drawn is that the biosecurity plan has been a failure.
Weak biosecurity conditions and self-regulation by the multinational salmon companies has created this obscene situation and yet the Rockliff government continues to back in an industry gone rogue that is destroying our marine environment.
The EPA has also published results from sampling to test antibiotic levels in wild fish following the dumping of oxytetracycline on the Zuidpool lease in the D’Entrecasteaux Channel, but the sampling was done over two kilometres from the lease and no testing of wild fish within the lease has been made public.
Tasmanian anglers can have no faith in these results. It is clear the EPA is hindered from doing robust and independent monitoring and desperately needs reform and additional resourcing.
The Greens once again call for this reform of the EPA, and demand the industrial salmon industry be reigned in and made accountable through a comprehensive parliamentary inquiry into this disaster.
Media Release — Ian Sale, Friends of the Bays, 6 May 2025
The Unprecedented salmon emergency is over, so say the EPA
Friends of Bays is a community group first formed at Clifton Beach two years ago with a specific aim to oppose the further spread of salmon pens into Storm Bay.
It has been a wild ride since then, and we now find ourselves one of several community groups holding a shared concern regarding the relentless expansion of the industry, aided and abetted by our two major political parties competing to be more supportive of the industry than the other.
Other than politics, the summer in southern Tasmania has been dominated by what has been described as an unprecedented salmon mortality event in the south-east. We are told that this was caused by a rickettsia bacteria that has been living in Tasmanian waters for some time.
Compared to other problems such as amoebic gill disease, rickettsia had not been a major concern.
Until now! This summer saw a mortality event that easily outstripped the 2021 Macquarie Harbour incident. Decomposing fish fragments washing ashore on several beaches after the salmon companies were overwhelmed by the scale of the kill.
Well, according to the EPA, the emergency is over.
We certainly welcome the news of a reduction in salmon deaths over the month of March. This was predictable if only because there were now far less fish available to die. Nonetheless, according to the EPA 3,395 tonnes of fish died during March. Assuming a weight of around 4kgs, this translates to around 850,000 fish deaths.
Altogether, using the February and March EPA figures, around 2.5 million fish deaths are known to have occurred. We believe this to be an underestimate of the carnage.
The EPA does not make the count. They rely on figures supplied by the companies, and they have an incentive to be conservative in their reports. Furthermore, in an overwhelming incident how can you count the many fish that have died, decomposed and then washed on to various shores several kilometres away.
Our organisation is also suspicious that some dead fish may have been dumped at sea.
Friends of the Bays had hoped that the EPA might adopt a more independent and open line following changes at the top. We were naive. The current media release looks like it was probably run past Salmon Tasmania before being released to the public.
And what now? The event is over so move on, nothing to see here?
The infectious agent is similar to one that has caused havoc to the salmon industry in Chile over many years. Vaccines have been of limited value there, and as a result antibiotics have been used in vast amounts to control infection outbreaks.
Is this the future for Tasmania? Why will things be any different next summer, or the summer after that.
Any thought of industry expansion must be put on hold. The antipathy to the industry in coastal communities is evidenced by the strong vote for salmon campaigners in Sandford, Middleton, Dodges Ferry and so on all around the South East coast. And that unrest has now arrived to the north coast.
The patronising and dismissive tone of Salmon Tasmania utterances only fuel that antipathy, as does the willful impotence of the EPA.
An event being unprecedented does not mean it will not happen again. It did in Chile. Climatic changes affecting sea temperatures will steadily increase.
What will Salmon Tasmania say next year when more fish die? And what will the EPA say? Probably the same thing.
We say that there needs to be a moratorium on salmon farm expansion together with an independent public enquiry with powers similar to a royal commission to better understand what happened this year and why, will it happen again, and what other adverse effects are arising from this odious industry.
Media Release — Bob Brown Foundation, 6 May 2025
Fish farms must be shut down after EPA figures reveal 2 million salmon deaths in 2 months
Figures released today show that at least 10,000 tonnes, a minimum of 2 million salmon*, died as a result of the catastrophic disease that spread throughout Tasmanian factory salmon farms in February and March of this year.
Bob Brown Foundation is calling for the complete removal of factory salmon farms from Tasmania’s waterways and a full independent investigation into the mass mortality event.
“These horrifying numbers of fish deaths confirm that the toxic salmon industry is out of control,” said Alistair Allan, BBF Antarctic and Marine campaigner.
“The images of rotting, dead fish floating in pens shocked the Australian public. To learn the true scale of this disaster, months later, that at least 2 million fish died due to the greed of foreign-owned corporations, is more proof that fish farms must get out of Tasmania’s waters.”
“What happened this summer is just the start. Every year, as waters get warmer, these disasters will get worse and more frequent. We must act now to protect Tasmania’s unique waters and prevent such large-scale cruelty and death in these factory farms of the sea.”
*Figure based on average harvest weight of a Tasmanian Farmed Salmon (4-5kg).
Media Release, Environment Protection Authority, 5 May 2025
March data shows decline in fish deaths and one hundred percent of salmon mortality waste beneficially reused
Mortality weight data submitted to the Environment Protection Authority (EPA) for the month of March shows that fish deaths declined by almost half compared to February 2025.
“The EPA can report that 100% of the salmon mortality material was beneficially reused through rendering, composting or use as fertiliser on agricultural properties,” said CEO, Catherine Murdoch.
“Water temperatures are falling and there has been a significant decline in the number of pens above the mortality reporting thresholds in April.”
Data provided to the EPA indicates that the unprecedented mortality event is over. The EPA will continue to receive and monitor mortality data.
Independent environmental monitoring conducted by the EPA of water quality and beach sediments at four beaches in the southern D’Entrecasteaux Channel found all samples to be below the detection limit for the antibiotic oxytetracycline.
“As part of this program the EPA collected water samples in the last 2 weeks of March at 10 offshore locations and a significant number of wild fish at four locations within the southern D’Entrecasteaux Channel for analysis and none of these samples detected any antibiotic residues.
“The EPA considers the presence of antibiotics in the southern D’Entrecasteaux Channel to be back to background levels,” said Ms Murdoch.
Huon Aquaculture is continuing a mandatory antibiotic sampling program at its Zuidpool lease and reports will be published on the EPA web site in due course.
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