The Maugean skate might be gone before you even knew it existed.
A rare and ancient species of ray, it lives only in Tasmania’s Macquarie Harbour, an area of just 300 square kilometres. It goes about its business quietly in the tannin-stained waters, where it feeds on a single species of crab on the harbour floor.
So quietly does it go about its business that it was only discovered in 1988.
Scientists have been unravelling the mystery of this fish ever since, but one thing they’ve concluded is that the Maugean skate is a ‘relic’ species from tens of millions of years ago, and as continents have shifted its former Gondwanan range has shrunk until it finds itself today confined to a tiny harbour on the West Coast of Tasmania.
But after surviving millions of years, the Maugean skate is in real danger of extinction and the reason is hard to miss if you travel down to Macquarie Harbour.
For well over a decade, the harbour has been the flashpoint for the aggressive expansion of salmon farming in Tasmanian waters. The industry had been operating at a modest scale since the 1980s, but by 2011 all three major Tasmanian salmon farming companies had pens in Macquarie Harbour, and the Tasmanian government was green lighting a massive expansion of the industry.
In the years following, as the number of salmon stocked in the harbour increased radically, the harbour edged toward environmental collapse as dissolved oxygen levels dropped and the accumulated waste under the fish pens created ‘dead zones’. In the summer of 2017, over 1.3 million fish died from low oxygen levels and disease… but that was just the farmed fish. The impacts on the wild fish populations – including the Maugean skate – was only just being realised.
Turns out it was dire. The Maugean skate population is estimated to have almost halved between 2014 and 2021, and today it’s thought there are just 1000 individuals left in the wild.
Regardless, the Tasmanian government has just renewed the permits of the three major aquaculture companies operating in Macquarie Harbour, all of whom are now owned by multinational companies with dubious environmental records. And while the previous owners had blamed each other for the environmental mess, the new owners and the salmon lobby are in complete denial, blaming other industries entirely for the demise of the skate.
“The foreign-owned Tasmanian salmon farming industry and our state's Premier are on the warpath, determined to let nothing, not even the extinction of a wild and endangered marine species, get in the way of their corporate profiteering,” Tasmanian Greens Senator, Peter Whish-Wilson told federal parliament recently.
“Macquarie Harbour is the last place on earth you will find the ancient and critically endangered Maugean skate. The salmon industry has claimed they don't support or believe the best scientific advice showing that salmon farming is a key contributor to poor dissolved oxygen levels in the harbour, which are pushing the skate to extinction, or the recommendation that salmon biomass must be significantly reduced to give the skate the best possible chance of survival. Apparently, it differs from the industry's own science – presumably paid for by the salmon industry – but you'd expect them to say that, wouldn't you?”
“How sad is it that it has gotten to this? A critically endangered species is being pushed to the brink of extinction by an introduced, invasive species, the Atlantic salmon. It was totally avoidable, and it was all because one industry had too much power over government and the regulator – and it still does. It seems like the story of Tasmania. What is next – the swift parrot? Is it the handfish? This is one of the great moral challenges of our time, and we can't afford to fail. The world is watching. I implore the federal government to continue their efforts to save the skate.”
The fate of the Maugean skate hangs in the balance. Last year federal Environment Minister, Tanya Plibersek famously made a pledge of ‘zero extinctions’ under her watch, but that now looks set to be challenged. In response, the feds have stumped up $2.1 million to begin a captive breeding program for the skate and opened a three-month consultation period about the future of salmon farming in Macquarie Harbour.
But in the meantime, the industry powers ahead, polluting the harbour and slowly bringing to an end a species – and a story – millions of years old. Scientists believe the skate is one extreme weather event away from extinction.
“The Maugean skate must not be allowed to go extinct,” says Bob Brown Foundation Marine Campaigner, Alistair Allan. “The science is clear; fish farms must be removed from Macquarie Harbour.”
Take action to protect the Maugean skate. Make a formal submission to the Federal Environment Minister and ask her to reconsider the decision to allow salmon farming in Macquarie Harbour.