By Mike Foley
Tasmania’s $1 billion salmon industry will supply thousands of Australian households this Christmas, its fresh and smoked fish fillets a relatively cheap alternative to many seafood options.
But what is the environmental cost?
Salmon farming in Tasmania. Credit: Adam Gibson
Tasmania’s big three salmon producers – foreign-owned companies Huon, Tassal and Petuna – promote the industry as sustainable, with low environmental impacts. But the industry’s critics warn it is poorly regulated, environmentally harmful and expanding at an unsustainable pace.
Seafood shoppers face a difficult task in deciding who to trust, especially with political leaders gearing up for an election stoush over the future of the industry.
Fishy issues
Salmon farms have been blamed for environmental degradation around the Tasmanian coastline, antibiotics leaking into the food chain, algal blooms, dead seals and introduction of hundreds of thousands of escapee fish into the environment.
However, Salmon Tasmania chief executive Luke Martin, who heads the peak body for the industry, said the farms were a good fit for the Tasmanian environment.
“We know millions of Australians will have salmon on the menu this Christmas lunch, and by doing so, they are supporting the livelihoods of 5000 Australians living across regional Tasmanian communities,” Martin said.
“Salmon is also a responsibly sourced seafood farmed under the highest environmental regulatory conditions of any farmed protein in Australia.
“Aquaculture also eases demand pressure on our wild fishing stocks.”
A salmon farm in Tasmania.Credit: Getty Images/iStockphoto
Salmon Tasmania’s website states the regulations strike a balance between growing a vital protein source, which is produced with minimal environmental impacts due to careful management.
The industry states its physical footprint on the water is 4000 hectares, compared to 426 million for agriculture on land.
“Tasmanian waterways are not, and never can be, overrun by salmon pens,” it said.
Green gripes
However, environmental groups paint a different picture.
“The industry puts into the sea more pollutants than all of Tasmania’s sewage outfalls combined,” said Australian Marine Conservation Society sustainable seafood program manager Adrian Meder.
The organisation’s GoodFish sustainable seafood guide told shoppers to reject Tasmanian farmed salmon this Christmas, warning that the huge expansion of the industry’s footprint “could lead to high environmental impacts”.
Wild fish kilometres from salmon farms have been found with antibiotic residue in their flesh. There are strict health guidelines around food containing antibiotics, due to the potential for uncontrolled use to lead to the creation of so-called superbugs in the human population.
Farmed salmon are sometimes treated with antibiotics to prevent infections that can kill fish or hurt production levels. The Salmon Tasmania website said only its veterinarians can prescribe antibiotics.
Meder said nutrient-rich salmon waste is churned out from salmon pens, disrupting the marine ecosystem. It has been linked to algal blooms that have, in some instances, clogged inshore reefs in several locations near farms.
A Tasmanian parliamentary inquiry completed in 2022 warned that the industry’s rapid growth had been facilitated by the state government, which is “an enthusiastic promoter and supporter of the industry”.
It included several scientific expert submissions that warned about algal outbreaks and issued a recommendation for “ceasing operations in sensitive, sheltered and biodiverse areas” – a call Meder said had been ignored.
Salmon Tasmania rejected these claims.
“We do not know who the Australian Marine Conservation Society is, what their agenda is, or who funds them, but we are very confident in the sustainability of our operations across Tasmania,” Martin said.
Harbouring doubts
Macquarie Harbour on Tasmania’s west coast is not the main source of salmon supply, producing around 13 per cent of annual production.
But it is where the most controversial leases are, because it is the only home for the incredibly rare and ancient relic, the Maugean skate, of which there are only 40 to 120 adults left in the wild.
Salmon farming began there in the late 1980s, and all three of Tasmania’s salmon companies, Tassal, Huon and Petuna, operate in the waterway. They have recently scaled back the size of their operations as concerns about the industry’s impact on the critically endangered fish grew.
The federal government’s threatened species committee said in August the best way to save the endangered fish was to eliminate, or at least dramatically cut back on, salmon farming in its habitat.
The committee said there was a “significant correlation” between low oxygen levels and an increase in salmon farming. Farmed fish suck up a lot of the oxygen in the water, while fish food and faeces that enter the water via the salmon pens feed oxygen-consuming bacteria.
Salmon farmers are trialling mechanical systems that push micro bubbles of oxygen to the bottom of the harbour.
“No fish farming should ever pose an extinction threat to an endangered species, and no other fish farming industry in Australia does,” Meder said. “It’s actually really easy to do fish farming better than this.”
Salmon Tasmania has warned that scaling back the industry could cut the 260 local jobs that it generates and claimed that multiple factors affected water quality, not just farming, including climate change and disruption from hydroelectric dams to river flows into Macquarie Harbour.
Political fallout
Federal Environment Minister Tanya Plibersek has on her desk a request from environment groups to revoke licences for farming in Macquarie Harbour, but a decision is not expected before an election due by May.
Opposition Leader Peter Dutton has accused the government of seeking to shut down the salmon industry. “The government’s prepared to hang the local community out to dry,” he said this month.
Macquarie Harbour is in the Braddon electorate, which the Liberal Party won from Labor at the 2019 election.
Prime Minister Anthony Albanese has hopes to win Braddon back. He visited on December 14 and declared he would not pre-empt Plibersek’s legal responsibilities as environment minister, but nevertheless guaranteed the industry would continue under his leadership.
Prime Minister Anthony Albanese visits salmon farms in Macquarie Harbour, on Tasmania’s west coast.
“As long as I’m prime minister, there will be support for jobs here in Tasmania because I understand how important it is for the Tasmanian economy,” Albanese declared. Plibersek was absent from his visit.
However, Plibersek said on December 19 that she welcomed the prime minister’s presence in Tasmania and echoed his support for the industry.
But it was far harder to interpret her position on the future of the industry, which she said must be weighed against environmental concerns.
“We know that the salmon industry is important for local jobs in Tasmania, but we also know that Tasmanians really value their natural environment … I’m not going to comment on any decision that is before me at the moment.”
Cut through the noise of federal politics with news, views and expert analysis. Subscribers can sign up to our weekly Inside Politics newsletter.