Thousands of dead fish, a $37m federal promise and an animal close to extinction: Australia’s ‘salmon war’ gets ugly

As the prime minister cemented his support for Tasmanian fish farming by tucking into grilled salmon and potato salad at a community barbeque in Devonport last weekend, a crisis was unfolding for the industry on the other side of the state.

Salmon pens around D’Entrecasteaux Channel and the Tasman Peninsula in the south-east of Tasmania – each containing up to 100,000 fish – became infected with bacteria last week, killing off more than five to 10 per cent of the fish in what is known in the industry as a “mass mortality event”.

“It’s one of the worst mortality rates the industry has seen in particular parts of the state,” says Luke Martin, chief executive of Salmon Tasmania, an industry group representing the three main salmon companies: Tassal Aussie Seafood, Huon Aquaculture and Petuna Seafood.

Members of the public found chunks of dead fish and greasy balls of fish fat washed up at Verona Sands in Huon Valley and spotted workers from Huon Aquaculture cleaning the beach, later confirmed by the company in a Facebook post. The state’s Environment Protection Authority tested the substances and confirmed their origin was salmon. A few days later, the same thing happened on Bruny Island.

The Bob Brown Foundation, an activist organisation opposed to salmon farming in public waters in Tasmania, captured drone footage of Tassal and Huon salmon workers in Dover hauling thousands of dead fish out of the water and filling multiple skip bins. Photos also emerged of salmon carcasses in landfill at the Copping waste depot near Port Arthur. Martin confirmed the tip had been used to dispose of fish as a “last resort”.

It’s caused a big stink, in both senses of the word.

“This is in no way a normal event,” says Eloise Carr, Tasmanian director of the left-leaning think-tank Australia Institute. “It’s horrific, and it’s the sign of an industry that’s out of control.”

The outrage about the fish kill is the latest salvo in the salmon wars, a political debate as protracted and polarised as forestry or mining.

Salmon is a northern hemisphere fish farmed in protected coastal waters around Tasmania. The industry directly provides about 2000 jobs, many in rural and remote parts of the state, and produces nearly 75,000 tonnes of fish a year, state government figures show.

A number of organisations including the Bob Brown Foundation and Neighbours of Fish Farming oppose salmon farming anywhere in the state because, they say, it is a dirty, polluting industry that releases salmon effluent and antibiotics into the natural environment, harms seals and other wildlife, and unsustainably feeds the carnivorous salmon with other fish including Antarctic krill, a key food source for whales and penguins.

Chunks of salmon fat mixed with sand washed ashore at Verona Sands, Tasmania.Credit: The Bob Brown Foundation

Martin says aquaculture gets more scrutiny than land-based agriculture, but he argues its environmental footprint is “comparable to every other type of protein production anywhere in the world”.

Nowhere is this debate over salmon more heated than in Macquarie Harbour, a huge body of water on the west coast of Tasmania that is home to the endangered dinosaur-era Maugean skate and about 12 per cent of the state’s salmon production.

Since November 2023, federal Environment Minister Tanya Plibersek has been reviewing whether salmon farming needed to be assessed under federal environmental laws because of the threats to the skate.

This month, Prime Minister Albanese pre-emptively declared he would pass special legislation to protect the salmon industry in Macquarie Harbour, badging the move as providing “certainty” and “protecting jobs”. On his previous visit in December, he declared his support for the industry but indicated the legal process should run its course.

Albanese promised the special legislation in a letter to the three salmon companies and then elaborated in media interviews last week. The news prompted outraged condemnation from every state conservation council in the country.

By last weekend Albanese was at the barbeque at Petuna Seafood in Devonport, putting his mouth where his money was by eating salmon, alongside Senator Anne Urquhart, who is running for Braddon. The vast seat, which encompasses nearly all of Tasmania’s west coast and half of the north, is held by Liberal MP Gavin Pearce on a margin of 8.03 per cent.

Anthony Albanese enjoying grilled salmon and potato salad at Devonport last weekend.Credit: Internet

He used the visit to announce $37 million to help the industry improve oxygenation levels in Macquarie Harbour and to improve the captive breeding program for the Maugean skate. “I want jobs, but I also want sustainability,” Albanese told reporters. “That’s what we’re delivering here. And there won’t be a reversal.”

Albanese would be mindful of the salmon vote not just in Braddon but across Tasmania, including in the marginal Labor seat Lyons and the marginal Coalition seat, Bass, both of which contain salmon farms. The Coalition also supports the aquaculture industry.

There are also many opponents – thousands of people show up to rallies against salmon farms and if you believe Australia Institute polling, seven out of 10 Tasmanians want fish farms out of inshore waters. Anti-salmon candidates are running as independents in some seats.

Salmon Tasmania’s Martin rejects the institute’s results as “push polling” and says opposition to the industry is only about 25 per cent statewide. He welcomes the prime minister’s commitment, saying the salmon companies were always confident the science would find them sustainable, but the process “dragged on far too long” and was vulnerable to legal challenge.

This masthead contacted the three salmon companies individually. Tassal, Petuna and Huon nominated Salmon Tasmania to speak on their behalf.

Albanese pointed to the latest research on the Maugean skate from the Institute for Marine and Antarctic Studies (IMAS) at the University of Tasmania to justify legislative protection for the Macquarie Harbour salmon industry.

The Maugean skate was discovered in 1988 and listed as endangered in the early 2000s, though it was only formally described by science in 2007. IMAS scientist Dr David Moreno says the threat to the species includes the fact it is “micro-endemic”, meaning it has a tiny home range. The skate is only known to live in Macquarie Harbour, with less certainty about its presence in Bathurst Harbour further south.

Macquarie Harbour is no stranger to epic environmental battles – it sits at the mouth of Franklin-Gordon Rivers, famously saved by Bob Hawke in 1983, and the King River. About a third of the harbour is in what is now the Tasmanian Wilderness World Heritage Area. It is six times larger than Sydney Harbour, with a narrow opening to the sea.

In 2023, IMAS sounded the warning on a calamitous decline in Maugean skate numbers in the harbour. Later the same year, the government’s conservation advice warned the skate population was expected to decline between 89 per cent and 99 per cent by 2041, putting the animal on the path to extinction. The warning came with a recommendation to either radically reduce the number of farmed salmon in the harbour or environmental remediation strategies to increase the amount of oxygen in the water.

If the skate becomes extinct, it would be the highest profile extinction for Tasmania since the Thylacine or Tasmanian tiger in the 1930s. The Albanese government famously promised there would be “no new extinctions” on its watch.

Concerns over the skate prompted the Australia Institute, Bob Brown Foundation and Australian Marine Conservation Society to write to Plibersek requesting the review of the decision that salmon farming did not need to be assessed under the Environment Protection Biodiversity Conservation Act. The minister initiated the review but has not completed it 14 months later.

As soon as the Maugean skate was discovered it was declared endangered.Credit: Dr Neville Barrett

Last October 30 scientists including 14 professors and five fellows from the Australian Academy of Science wrote an open letter to Plibersek urging her to listen to the science. More recently the Australia Institute wrote to UNESCO asking for a delegation to review the threats to the World Heritage Area.

An FOI in January produced documents showing the Australian government is still deciding whether to list the skate as critically endangered.

The latest research from the IMAS was published earlier this month, reporting positive news for the skate with the estimated population back to 2014 levels.

IMAS scientist Dr David Moreno says there have been a couple of good years environmentally, with natural water flow from the ocean refreshing the oxygen levels in the harbour, and this correlated with good years for the skate. The salmon industry has been trialling oxygenation technology, but Moreno says most of the replenishment of oxygen was through natural processes.

Despite the good news, Moreno says the scientists are cautious, noting Maugean skates live about 10 years and do not reach sexual maturity for five years, so a rough year could set things back. “It’s still a little bit too early to absolutely declare that we’ve turned the point and that everything is fine,” Moreno says.

IMAS also has two adult Maugean skates and a clutch of “incredibly cute” baby skates that hatched from eggs collected from the wild or laid by the adult female that was already pregnant when caught. Moreno says the breeding program will start once the scientists understand the genetics and the intention is to eventually release them back into the wild.

If the idea behind the special legislation is to protect jobs, how do the economics stack up?

Tasmanian government figures suggest there are 1789 full-time and 379 casual jobs across the state. Salmon Tasmania’s Martin estimates about 120 people are employed directly on the salmon farms in Macquarie Harbour, about half of whom live in Strahan and the other half who drive in and out from towns in the north-west such as Burnie, Devonport and Launceston.

Deloitte analysis, commissioned by the salmon industry, estimates there are 5000 jobs across the state if you include indirect jobs in the supply chain. Martin says about 400 are in the north-west.

Carr says 80 per cent of the jobs in the salmon industry are in Hobart or south of Hobart, and it would be affordable to help the small proportion employed in Macquarie Harbour to transition to different industries. “This is totally urgent, the skate remains on the brink of extinction and nothing that has happened since then has changed that,” Carr says.

Beyond Macquarie Harbour, Carr says government money would be better spent supporting companies to move aquaculture operations on shore.

Martin describes this as “Alice in Wonderland stuff” given the logistics, including the water demand. Yet, Washington state in the United States, British Columbia in Canada and Tierra del Fuego in Argentina have banned aquaculture in the sea, with some moving instead to closed systems for farming salmon on land.

As waters warm, scientists warn that Tasmania’s oceans will become increasingly unfriendly for salmon farming.Credit: The Bob Brown Foundation

The three salmon companies were once Australian enterprises, but are now owned by multinationals. Petuna is owned by New Zealand’s Sealord, Huon Aquaculture by Brazilian giant JBS and Tassal by Canadian company Cooke.

This year’s mass fish kill won’t help the bottom line for Huon and Tassal and last year all three companies were affected by a similar event in Macquarie Harbour.

Martin says the industry always has some mortality, especially in summer when the waters are warm, but this year a “severe” outbreak set in before the companies could vaccinate the fish. Usually, dead fish are rendered into fertiliser or fish feed, Martin says, but this time the “scale … and urgency” meant approved landfill sites had to be used. He expects the mortality event to be over in a few weeks.

Fish expert Culum Brown, associate professor in biological sciences at Macquarie University, says fish get stressed when water temperatures are high, which hampers their immune system’s capacity to fight infections. Wild fish might swim to cooler waters, but fish trapped in pens cannot escape.

“If something goes wrong, it tends to go horribly wrong, and you can lose a lot of fish in a very short period of time,” Brown says.

Alex Sen Gupta, a climate expert at the University of NSW, says the Tasman Sea was considered a “warming hotspot” because it was heating two to three times faster than the global average ocean temperatures over the past few decades. This summer’s marine heatwave is two degrees warmer than the 1991-2020 average in some parts of the sea.

Martin says the salmon industry understands the threat of climate change and is investing in resilient fish stocks. But Brown says Australian waters are not cool enough and are becoming less so for a cool water fish from the northern hemisphere. “Salmonids in Australia have a bleak future,” he says.

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