Salmon critics say fish farms should be on land. How it works for Murray cod
The pelicans perusing the perimeter and kites circling above see what the untrained human eye cannot – beneath a protective net, the water is teeming with Murray cod.
The ponds are part of the operations of Murray Cod Australia, trading as Aquna Sustainable Murray Cod. Chief executive Ross Anderson explains the colour of the water is by design – it's because the staff promote the growth of beneficial native algae.
Together with the water plants around the ponds' edges, the algae absorbs the nutrients from the fish poo and releases oxygen into the water by night. This results in less water usage and reduced need to mechanically oxygenate the water; an energy saving.
Another benefit: the algae creates a living culture that consumes other byproducts of the fish, preventing the build-up of chemical compounds that change the flavour of the fish.
'It's quite counter-intuitive, but from this muddy, green looking water, you get a clean, white-tasting fish,' Anderson says. 'Whereas in an artificial system in a tank … from that crystal clear water, you'll often end up with a muddy-tasting fish.'
While Anderson refrains from discussing the environmental woes facing the Tasmanian salmon industry, the contrasts are obvious.
Farmed salmon are fed ground-up wild fish – putting pressure on other ecosystems such as Antarctica – and antibiotics. Aquna feeds its Murray cod sustainable fish feed made from crops such as lupin, chickpeas and soybean and offcuts from chicken, beef and lamb – and their water quality control means they don't need to use antibiotics.
Salmon are farmed in open pens in the sea, releasing effluent into the water. In an unprecedented mortality event this summer, thousands of tonnes of dead salmon washed up on beaches in south-east Tasmania. Murray cod are farmed on land in ponds with no connection to natural waterways, using a relatively small amount of water from the Snowy Hydro scheme that later irrigates land including crops.
Salmon is threatening the critically endangered Maugean skate in Macquarie Harbour in western Tasmania. Aquna is helping state governments restock the vulnerable native Murray cod in the Murray-Darling basin.
The mass fish kill in Tasmania was caused by a bacterial outbreak against the backdrop of a marine heatwave, a problem that will probably recur as climate change worsens, unless the industry can adapt. Murray cod have evolved to withstand a wide range of temperatures and swings between drought and flood.
Aquna co-founder Mathew Ryan says he was drawn to aquaculture because the world needs to increase protein production using fewer resources, and specifically Murray cod because he wanted to stay in the Riverina and provide local jobs.
'Aquaculture was something that always fascinated me because the amount of production that you can get from a hectare of land [used for aquaculture] or from a megalitre of water is quite phenomenal,' Ryan says.
Murray cod is technically a perch but has an oily, white flesh like cod – I tried the Aquna product and found it had a delicate flavour and a satisfying meatiness. Some consumers are buying it instead of salmon, while in restaurants it competes with coral trout and Patagonian toothfish.
The company now has multiple properties near Griffith, with hatchlings in indoor tanks, juveniles in nursery ponds, and bigger fish in grow-out ponds. Anderson explains the fish have to be kept with others of the same size otherwise the bigger fish will eat or injure the smaller fish.
At the grow-out site with ponds dug out of the local clay soil, Ryan estimates 100-200 megalitres of water a year will produce 1000 tonnes of fish. By contrast, it takes 3800-4400 megalitres of water to produce 1000 tonnes of almonds, not including the shells, based on figures from the Almond Board of Australia and analysed by this masthead.
The company leans heavily into the sustainability of its operation in its pitch to consumers, marketing its product as fish 'for foodies who care where their fish comes from'. It does have the backing of the Australian Marine Conservation Society's GoodFish guide, which endorses farmed Murray cod from NSW and Victoria as well as farmed barramundi (but not wild caught) from all over Australia.
As the salmon industry grapples with social licence not just in Tasmania but around the world, many critics are calling for the fish to be farmed on land.
Industry group Salmon Tasmania has rejects this as fanciful, saying it would require too much land, water and energy and be five to 10 times more expensive. Independent aquaculture experts confirm there are significant logistical challenges.
'There is no single company with a major salmon farming initiative on land that is profitable, so it is, as yet, an undeveloped concept,' says Professor Tim Dempster, an expert in marine biology and aquaculture at Deakin University.
That's not the case for other species. Land-based aquaculture is the dominant form of fish farming globally, practised for centuries, especially in Asia. But is it more sustainable?
The main knock-on effect of farming salmon in the sea in Tasmania is the effluent that pollutes the marine environment. Dempster says New Zealand only avoids this problem because the industry is much smaller and more spread out.
In the salmon-producing countries of the northern hemisphere, such as Canada, Norway and Scotland, the main environmental concern is lice from farmed fish infecting wild salmon and reducing stocks, Dempster says.
Canada has decided to remove open-net salmon farming from British Columbia by June 2029 and told the industry it must transition to land-based systems.
Dempster doubts this will happen – he says the industry will probably move elsewhere.
Norway is experimenting with farming salmon onshore, but it is not a model for Tasmania because it is releasing the untreated seawater back out into the fjords, with the goal to direct the water to places where lice are least likely to infest wild fish.
There is also a fully self-contained approach – a 'recirculating aquaculture system' where the water is treated and reused. Atlantic Sapphire has spent $US1 billion ($1.55 billion) since 2011 pursuing this in Florida and is still bleeding money.
Farming salmon on land removes some environmental harms, but it is vastly more carbon intensive – both to build the tanks, and maintain the cool, clear water with high oxygen levels that salmon require.
Dempster says a salmon pen in the ocean in Tasmania might contain 50,000 cubic litres of water and produce 500 tonnes of fish. Salmon production in the state is 75,000 tonnes a year, according to Salmon Tasmania, so the volumes of water are vast.
Dempster says there are about 200 species globally that are farmed on land – mostly freshwater fish that can cope with lower water quality and higher temperatures, and don't require wild fish in their diet. (Marine fish need a source of Omega 3).
In Australia, there are several native fish that are suitable. Besides Murray cod there is the perennial pub favourite barramundi, which is both wild caught and farmed in tanks, ponds or occasionally the ocean, throughout Australia and Asia. Dempster says the environmental impacts are small.
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Globally, most land-based aquaculture around the world is done in tanks, and some of it is not environmentally sustainable at all.
'In some countries, say in China, where they are farming a lot of carp, they pour a lot of fertiliser in to fertilise those water bodies because the carp [eat plankton], and that then leads to that a lot of those nutrients exiting into the environment,' Dempster says.
'It depends on the species, the location and the farming system as to how good that system is for the environment.'
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The Advertiser
3 days ago
- The Advertiser
Apology for diesel pollution as Kurri power plant fires-up for next round of testing
Snowy Hydro has apologised for allowing diesel fumes to spew across the Lower Hunter communities during the first round of testing of the new $2 billion Hunter Power Project. But it has warned there may be more foul odours to come when it starts testing with gas this week. Residents from Kurri Kurri to Belmont, Newcastle and West Wallsend said they smelt a strong, burning diesel-like smell on July 8 and 9. Some reported burning eyes and breathing issues. Testing was stopped following the widespread complaints. "We sincerely apologise for not meeting community expectations regarding providing information about the testing more broadly across the region," Snowy Hydro said in a statement. Gas, the 660-megawatt plant's primary fuel, will be used for the next round of testing, which will commence on Monday. Snowy Hydro warned there may be a potential plume and associated noise and odour when the turbine starts up again. "While these impacts will only last a short period and will be dependent on weather conditions at the time of testing, we have also increased the level of air monitoring outside the site boundary," the company said. "The nature of turning on a brand new generator for the first time means there is uncertainty regarding how it will perform as we fine-tune the turbines so they operate efficiently when we switch to full operations." A NSW Environment Protection Authority spokesman said the agency's investigation into the first pollution incident was ongoing. He said the EPA was finalising a review of Snowy Hydro's additional control measures to manage emissions and ensure the community was adequately consulted. "We are pleased Snowy Hydro has committed to increasing the amount of monitoring and has strengthened community engagement," he said. "As part of its Environment Protection Licence for the site, the power station is required to conduct continuous emissions monitoring, including during this commissioning phase, where emissions are usually higher than normal operation." EPA officers will monitor the commissioning work, including conducting odour surveys in the area while the commissioning is undertaken. Once fully tested, the efficiency of the turbines will result in significantly reduced emissions. Testing will be undertaken at night and is expected to take six to eight weeks. Improvements to noticeable emissions and odour are expected each week as the commissioning process progresses. The Hunter Power Project was originally intended to be built in time for the closure of the Liddell coal-fired power station in April 2023. It is expected that the peaking plant will be used for only about 5 per cent of the time once it is fully operational. Prime Minister Anthony Albanese, along with Hunter MPs, committed an additional $700 million towards the green hydrogen project on the eve of the 2022 federal election. Labor had hoped to start running the plant on 30 per cent green hydrogen from day one and ramp up to 100 per cent by 2030. While the plant's open-cycle gas turbines have been designed to allow for a 15 per cent hydrogen-gas blend, it quickly became apparent that the green hydrogen dream was technically impossible within the proposed timeframe. Snowy Hydro has apologised for allowing diesel fumes to spew across the Lower Hunter communities during the first round of testing of the new $2 billion Hunter Power Project. But it has warned there may be more foul odours to come when it starts testing with gas this week. Residents from Kurri Kurri to Belmont, Newcastle and West Wallsend said they smelt a strong, burning diesel-like smell on July 8 and 9. Some reported burning eyes and breathing issues. Testing was stopped following the widespread complaints. "We sincerely apologise for not meeting community expectations regarding providing information about the testing more broadly across the region," Snowy Hydro said in a statement. Gas, the 660-megawatt plant's primary fuel, will be used for the next round of testing, which will commence on Monday. Snowy Hydro warned there may be a potential plume and associated noise and odour when the turbine starts up again. "While these impacts will only last a short period and will be dependent on weather conditions at the time of testing, we have also increased the level of air monitoring outside the site boundary," the company said. "The nature of turning on a brand new generator for the first time means there is uncertainty regarding how it will perform as we fine-tune the turbines so they operate efficiently when we switch to full operations." A NSW Environment Protection Authority spokesman said the agency's investigation into the first pollution incident was ongoing. He said the EPA was finalising a review of Snowy Hydro's additional control measures to manage emissions and ensure the community was adequately consulted. "We are pleased Snowy Hydro has committed to increasing the amount of monitoring and has strengthened community engagement," he said. "As part of its Environment Protection Licence for the site, the power station is required to conduct continuous emissions monitoring, including during this commissioning phase, where emissions are usually higher than normal operation." EPA officers will monitor the commissioning work, including conducting odour surveys in the area while the commissioning is undertaken. Once fully tested, the efficiency of the turbines will result in significantly reduced emissions. Testing will be undertaken at night and is expected to take six to eight weeks. Improvements to noticeable emissions and odour are expected each week as the commissioning process progresses. The Hunter Power Project was originally intended to be built in time for the closure of the Liddell coal-fired power station in April 2023. It is expected that the peaking plant will be used for only about 5 per cent of the time once it is fully operational. Prime Minister Anthony Albanese, along with Hunter MPs, committed an additional $700 million towards the green hydrogen project on the eve of the 2022 federal election. Labor had hoped to start running the plant on 30 per cent green hydrogen from day one and ramp up to 100 per cent by 2030. While the plant's open-cycle gas turbines have been designed to allow for a 15 per cent hydrogen-gas blend, it quickly became apparent that the green hydrogen dream was technically impossible within the proposed timeframe. Snowy Hydro has apologised for allowing diesel fumes to spew across the Lower Hunter communities during the first round of testing of the new $2 billion Hunter Power Project. But it has warned there may be more foul odours to come when it starts testing with gas this week. Residents from Kurri Kurri to Belmont, Newcastle and West Wallsend said they smelt a strong, burning diesel-like smell on July 8 and 9. Some reported burning eyes and breathing issues. Testing was stopped following the widespread complaints. "We sincerely apologise for not meeting community expectations regarding providing information about the testing more broadly across the region," Snowy Hydro said in a statement. Gas, the 660-megawatt plant's primary fuel, will be used for the next round of testing, which will commence on Monday. Snowy Hydro warned there may be a potential plume and associated noise and odour when the turbine starts up again. "While these impacts will only last a short period and will be dependent on weather conditions at the time of testing, we have also increased the level of air monitoring outside the site boundary," the company said. "The nature of turning on a brand new generator for the first time means there is uncertainty regarding how it will perform as we fine-tune the turbines so they operate efficiently when we switch to full operations." A NSW Environment Protection Authority spokesman said the agency's investigation into the first pollution incident was ongoing. He said the EPA was finalising a review of Snowy Hydro's additional control measures to manage emissions and ensure the community was adequately consulted. "We are pleased Snowy Hydro has committed to increasing the amount of monitoring and has strengthened community engagement," he said. "As part of its Environment Protection Licence for the site, the power station is required to conduct continuous emissions monitoring, including during this commissioning phase, where emissions are usually higher than normal operation." EPA officers will monitor the commissioning work, including conducting odour surveys in the area while the commissioning is undertaken. Once fully tested, the efficiency of the turbines will result in significantly reduced emissions. Testing will be undertaken at night and is expected to take six to eight weeks. Improvements to noticeable emissions and odour are expected each week as the commissioning process progresses. The Hunter Power Project was originally intended to be built in time for the closure of the Liddell coal-fired power station in April 2023. It is expected that the peaking plant will be used for only about 5 per cent of the time once it is fully operational. Prime Minister Anthony Albanese, along with Hunter MPs, committed an additional $700 million towards the green hydrogen project on the eve of the 2022 federal election. Labor had hoped to start running the plant on 30 per cent green hydrogen from day one and ramp up to 100 per cent by 2030. While the plant's open-cycle gas turbines have been designed to allow for a 15 per cent hydrogen-gas blend, it quickly became apparent that the green hydrogen dream was technically impossible within the proposed timeframe. Snowy Hydro has apologised for allowing diesel fumes to spew across the Lower Hunter communities during the first round of testing of the new $2 billion Hunter Power Project. But it has warned there may be more foul odours to come when it starts testing with gas this week. Residents from Kurri Kurri to Belmont, Newcastle and West Wallsend said they smelt a strong, burning diesel-like smell on July 8 and 9. Some reported burning eyes and breathing issues. Testing was stopped following the widespread complaints. "We sincerely apologise for not meeting community expectations regarding providing information about the testing more broadly across the region," Snowy Hydro said in a statement. Gas, the 660-megawatt plant's primary fuel, will be used for the next round of testing, which will commence on Monday. Snowy Hydro warned there may be a potential plume and associated noise and odour when the turbine starts up again. "While these impacts will only last a short period and will be dependent on weather conditions at the time of testing, we have also increased the level of air monitoring outside the site boundary," the company said. "The nature of turning on a brand new generator for the first time means there is uncertainty regarding how it will perform as we fine-tune the turbines so they operate efficiently when we switch to full operations." A NSW Environment Protection Authority spokesman said the agency's investigation into the first pollution incident was ongoing. He said the EPA was finalising a review of Snowy Hydro's additional control measures to manage emissions and ensure the community was adequately consulted. "We are pleased Snowy Hydro has committed to increasing the amount of monitoring and has strengthened community engagement," he said. "As part of its Environment Protection Licence for the site, the power station is required to conduct continuous emissions monitoring, including during this commissioning phase, where emissions are usually higher than normal operation." EPA officers will monitor the commissioning work, including conducting odour surveys in the area while the commissioning is undertaken. Once fully tested, the efficiency of the turbines will result in significantly reduced emissions. Testing will be undertaken at night and is expected to take six to eight weeks. Improvements to noticeable emissions and odour are expected each week as the commissioning process progresses. The Hunter Power Project was originally intended to be built in time for the closure of the Liddell coal-fired power station in April 2023. It is expected that the peaking plant will be used for only about 5 per cent of the time once it is fully operational. Prime Minister Anthony Albanese, along with Hunter MPs, committed an additional $700 million towards the green hydrogen project on the eve of the 2022 federal election. Labor had hoped to start running the plant on 30 per cent green hydrogen from day one and ramp up to 100 per cent by 2030. While the plant's open-cycle gas turbines have been designed to allow for a 15 per cent hydrogen-gas blend, it quickly became apparent that the green hydrogen dream was technically impossible within the proposed timeframe.


The Advertiser
14-07-2025
- The Advertiser
Cultural and cool burn workshop to benefit koala habitat in Port Stephens
WITH a focus on enhancing koala habitats, biodiversity and fire management in the region, a cool burn educational workshop will be held in Port Stephens. Delivered by Port Stephens Council and the Worimi Green Team, the workshop will round out a successful three-year project aimed at cool burn land management techniques and their benefits. A cool burn, also known as a low-intensity burn, is a controlled burning technique that removes undergrowth and dry debris, while limiting the spread of invasive weeds without significantly impacting vegetation. The project is part of a number of on-ground burns in collaboration with Worimi Local Aboriginal Land Council, Bindelong Aboriginal Corporation Cool Burn Fire and Ecology, Hunter Local Land Services, and local members of the Rural Fire Service. Port Stephens Council mayor Leah Anderson said seeing the community and agencies come together to improve the koala habitat and promote cultural practices was special. "When we use culturally-informed cool burns alongside our fire management practices, it really gives our ecosystems a boost," she said. "These carefully planned burns are a valuable tool for looking after our land, helping to make our ecosystems stronger and supporting all the amazing plants and animals we have here in Port Stephens." She said it was amazing to see the use of traditional Aboriginal land management practices. "It's tapping into generations of wisdom, and it helps us get the best possible results for our local environment," she said. The culturally informed cool burn demonstration and educational workshop will be held on Saturday, July 19 at the Mallabula Community Centre. "This is a unique opportunity for the community to come and learn about the benefits of these practices in a truly special way," mayor Anderson said. WITH a focus on enhancing koala habitats, biodiversity and fire management in the region, a cool burn educational workshop will be held in Port Stephens. Delivered by Port Stephens Council and the Worimi Green Team, the workshop will round out a successful three-year project aimed at cool burn land management techniques and their benefits. A cool burn, also known as a low-intensity burn, is a controlled burning technique that removes undergrowth and dry debris, while limiting the spread of invasive weeds without significantly impacting vegetation. The project is part of a number of on-ground burns in collaboration with Worimi Local Aboriginal Land Council, Bindelong Aboriginal Corporation Cool Burn Fire and Ecology, Hunter Local Land Services, and local members of the Rural Fire Service. Port Stephens Council mayor Leah Anderson said seeing the community and agencies come together to improve the koala habitat and promote cultural practices was special. "When we use culturally-informed cool burns alongside our fire management practices, it really gives our ecosystems a boost," she said. "These carefully planned burns are a valuable tool for looking after our land, helping to make our ecosystems stronger and supporting all the amazing plants and animals we have here in Port Stephens." She said it was amazing to see the use of traditional Aboriginal land management practices. "It's tapping into generations of wisdom, and it helps us get the best possible results for our local environment," she said. The culturally informed cool burn demonstration and educational workshop will be held on Saturday, July 19 at the Mallabula Community Centre. "This is a unique opportunity for the community to come and learn about the benefits of these practices in a truly special way," mayor Anderson said. WITH a focus on enhancing koala habitats, biodiversity and fire management in the region, a cool burn educational workshop will be held in Port Stephens. Delivered by Port Stephens Council and the Worimi Green Team, the workshop will round out a successful three-year project aimed at cool burn land management techniques and their benefits. A cool burn, also known as a low-intensity burn, is a controlled burning technique that removes undergrowth and dry debris, while limiting the spread of invasive weeds without significantly impacting vegetation. The project is part of a number of on-ground burns in collaboration with Worimi Local Aboriginal Land Council, Bindelong Aboriginal Corporation Cool Burn Fire and Ecology, Hunter Local Land Services, and local members of the Rural Fire Service. Port Stephens Council mayor Leah Anderson said seeing the community and agencies come together to improve the koala habitat and promote cultural practices was special. "When we use culturally-informed cool burns alongside our fire management practices, it really gives our ecosystems a boost," she said. "These carefully planned burns are a valuable tool for looking after our land, helping to make our ecosystems stronger and supporting all the amazing plants and animals we have here in Port Stephens." She said it was amazing to see the use of traditional Aboriginal land management practices. "It's tapping into generations of wisdom, and it helps us get the best possible results for our local environment," she said. The culturally informed cool burn demonstration and educational workshop will be held on Saturday, July 19 at the Mallabula Community Centre. "This is a unique opportunity for the community to come and learn about the benefits of these practices in a truly special way," mayor Anderson said. WITH a focus on enhancing koala habitats, biodiversity and fire management in the region, a cool burn educational workshop will be held in Port Stephens. Delivered by Port Stephens Council and the Worimi Green Team, the workshop will round out a successful three-year project aimed at cool burn land management techniques and their benefits. A cool burn, also known as a low-intensity burn, is a controlled burning technique that removes undergrowth and dry debris, while limiting the spread of invasive weeds without significantly impacting vegetation. The project is part of a number of on-ground burns in collaboration with Worimi Local Aboriginal Land Council, Bindelong Aboriginal Corporation Cool Burn Fire and Ecology, Hunter Local Land Services, and local members of the Rural Fire Service. Port Stephens Council mayor Leah Anderson said seeing the community and agencies come together to improve the koala habitat and promote cultural practices was special. "When we use culturally-informed cool burns alongside our fire management practices, it really gives our ecosystems a boost," she said. "These carefully planned burns are a valuable tool for looking after our land, helping to make our ecosystems stronger and supporting all the amazing plants and animals we have here in Port Stephens." She said it was amazing to see the use of traditional Aboriginal land management practices. "It's tapping into generations of wisdom, and it helps us get the best possible results for our local environment," she said. The culturally informed cool burn demonstration and educational workshop will be held on Saturday, July 19 at the Mallabula Community Centre. "This is a unique opportunity for the community to come and learn about the benefits of these practices in a truly special way," mayor Anderson said.

ABC News
10-07-2025
- ABC News
Snowy Hydro apologises for burning diesel smell from Kurri Kurri power plant
A controversial Hunter Valley power station has caused a stink in its community, with the operator apologising for a pungent smell of fuel in the air. Snowy Hydro's plant at Kurri Kurri, which has just started its testing phase, is designed to run on gas, but can also be powered by diesel as a backup source. CEO Dennis Barnes said in the past week, testing took place on one of two turbines, which included testing it on diesel. "That caused some emissions and some odour, which we're deeply regretful for," he told ABC Newcastle Breakfast. "We weren't expecting it, and therefore we've stopped [testing]." Witnesses reported seeing plumes of smoke coming from the plant, while others more than 30 kilometres away in Newcastle reported the smell. Resident Marlie Forde said when she first noticed the smell, she thought it was a failing electrical appliance in her home. "It was just eye-watering, I've never smelt anything that bad," he said. "Even with all the windows shut, it just made me feel really sick and nauseous." Mr Barnes said the company was working with the NSW Environmental Protection Authority (EPA) in its investigations. "At the plant itself, the emissions were within our environmental limits, but that doesn't make any difference to the local community when they're smelling and seeing smoke," he said. Environmental advocate and former local Greens candidate Janet Murray has campaigned against the plant since it was first announced. "I heard the guy from Snowy Hydro saying that emissions were within their allowable limits," she told ABC Newcastle Mornings. "If that's allowable, that is ridiculous." In a statement, an EPA spokesperson said the plant was required to conduct continuous emissions monitoring, including during any testing in the commissioning phase. "Before commissioning works recommence, we will review Snowy Hydro's updated commissioning plan and discuss additional control measures," the statement read. "Our investigation into the recent emissions and odours is continuing, including checking whether the station's emissions limits have been breached." Ms Murray said communication from Snowy Hydro about the testing has been "woeful". "I have a friend who lives very close to the plant and he was given no advice whatsoever," she said. Mr Barnes conceded the company could have communicated with the wider Hunter region better. "We did do local communications and our near neighbours, but I think we've stuffed up by not going more broadly on social media and on the radio to warn people that we were doing this," he said. He said commissioning phase testing has stopped, but will eventually need to resume. "We'll figure out how we do that without impact between now and when that happens," he said. 'Until we can do that, we won't test it." The plant is designed to bridge electricity supply in times of peak demand, with the former Morrison government commissioning it to cover the gap as coal-fired power stations wind down and more renewable generators are developed.