Your salmon fillets could be driving a rare, ancient species to extinction

The salmon fillets you’re buying at the supermarket could be driving one of Australia’s rarest and most ancient animals to extinction.

There are between 40 and 120 remaining adult Maugean skate – a fish endemic only to western Tasmania – on the planet.

The Maugean skate is on the brink of extinction. It has a flat, disc-shaped body between 70 centimetres and 90 centimetres long and a thorny tail. Credit: Neville Barrett

Scientists on the federal government’s threatened species committee last week said the best way to save the endangered fish is to eliminate or at least dramatically cut back on salmon farming in its habitat.

Farms are located around the Tasmanian coastline, and Macquarie Harbour is not the main source of salmon supply. But that’s where the most controversial leases are because it is the only place on earth where the skate lives.

Salmon farming began there in the late 1980s and all three of Tasmania’s salmon companies, Tassal, Huon Aquaculture and Petuna, operate in the waterway.

The species is more than 60 million years old but it is so elusive – spending its life hunting crustaceans on the bottom of the harbour – that it was only discovered in 1988.

Since the discovery the population has crashed.

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.

Greens Tasmanian Senator Peter Whish-Wilson said shoppers should be aware that when they buy salmon at the supermarket, it could contribute to the skate’s extinction.

“I encourage people to question whether eating farmed salmon is worth contributing to the extinction of a prehistoric native species found nowhere else on earth.”

“For years the writing has been on the wall about the dangers of farming salmon in Macquarie Harbour … and now there’s a very real chance the ancient Maugean skate will go extinct in the wild because of it.”

Whish-Wilson said supermarkets bear responsibility for the species’ plight.

“They can simply say no to selling Tasmanian salmon products sourced from Macquarie Harbour and in turn do their bit to protect a species on the edge of extinction.”

Salmon Tasmania chief executive Luke Martin said his organisation would review the committee’s report.

He warned that scaling back farming would cost valuable jobs and argued multiple factors affected water quality, not only farming, like climate change and disruption from hydroelectric dams to river flows into Macquarie Harbour.

“The salmon industry, state government and federal government are all taking action to improve the harbour which incidentally is now at near its healthiest in a decade,” Martin said.

“There are absolutely no guarantees that simply ending salmon aquaculture in the harbour will save the skate. But it is 100 per cent certain reducing aquaculture in Macquarie Harbour will cost hundreds of jobs and devastate communities.”

The committee’s report serves as advice to federal Environment Minister Tanya Plibersek about the skate’s status, which it recommended being downgraded from endangered to critically endangered.

Critically endangered means that the probability of extinction in the wild will to be greater than 50 per cent in 10 years or three generations, whichever is longer.

The population of adult skates halved in the past 10 years and is projected to fall by 25 per cent in the next generation.

Plibersek will consider the committee’s advice, as well as public submissions that are open until September 26.

Plibersek is also reviewing licences for the salmon farms in Macquarie Harbour, under a separate process.

The government has set aside $5.7 million to improve the health of the harbour, including $2.1 million for a captive breeding program which last week announced the world’s first baby Maugean Skate hatched from a captive-laid egg.

Wilderness Society policy and strategy manager Tim Beshara said the government must act now to protect the species as extinction would be a unique example of a commercial industry’s role in biodiversity loss.

Atlantic salmon pens in Macquarie Harbour.Credit: Getty

“The science shows a direct connection between the industry, the commodity and the companies and the imminent extinction of a species,” Beshara said.

“The Maugean skate is a stupendously unique creature and its extinction would be the equivalent of losing the Wollemi Pine or the African elephant.“

Woolworths and Coles say they are closely monitoring the situation.

“We are aware of ongoing stakeholder concerns regarding the environmental impact of salmon farming at Macquarie Harbour, and it is an issue we are taking very seriously,” a Coles spokesperson said.

“We take this matter seriously and are actively engaged with interested parties,” a Woolworths spokesperson said.