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by Colin Cardwell
18 January 2024
Associate Feature: Swimming against the tide

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Associate Feature: Swimming against the tide

Stewart Hawthorn is clearly someone with strong convictions. The overriding one, he explains, is that business as usual isn’t good enough anymore. “Given the climate emergency and the major challenges regarding the environment we all face, we need to act now and embrace change on all levels – whether it’s the way we produce energy, the way we produce power, transport people and goods or in our case the way we produce food, allowing sustainable access to low carbon, animal protein sources for human health.”

Hawthorn (right) is managing director of Loch Long Salmon, the company that is seeking to bring semi-closed containment salmon farming technology to Scotland for the first time – a technology that is already being successfully deployed in Norway, Canada, and the Faroe Islands.

Traditional, open-net salmon farming is an industry that isn’t without its critics, something that Hawthorn acknowledges. “The reality is that, due to a combination of factors, the existing way of doing things results in a mortality rate that is far too high,” he explains. 

Among these factors are sea lice but there are others such as micro jellyfish, known as hydrozoans, which cause some previously unexplained gill health challenges and have become an international concern for producers, possibly due to the slightly warmer waters associated with climate change, he says. 

Semi-closed containment, as Hawthorn describes it, is also known as “closed containment” or “containment at sea” and has several major advantages. 

It works by totally surrounding the pen with a specialist membrane barrier that allows greater control of the environment and water within it, where the salmon are kept.

This addresses the main concerns around existing farming pens by preventing sea lice and fish escapes and eliminating predation by seals while also improving fish health and welfare.  
The technology, says Hawthorn, will also capture more than 85 per cent of solid waste and uneaten food, bringing it onshore where it will be treated to be used as a fertiliser or in biofuel or other green projects. 

Importantly, capturing the waste means that a site using this technology can produce more salmon than an open net farm with less organic discharge and no chemical use for treatment for sea lice or discharge of treatment chemicals into the water.

“Companies in Norway have been using and developing this technology since early 2014 and have been awarded full commercial licences since 2018,” he says.  “It’s now ready to be deployed in Scotland on a commercial scale and Loch Long Salmon will be the first to do it here.

“Commercial deployments overseas report better standards of welfare, significantly lower mortality rates and improved growth and survival rates. We believe that record, backed up by independent evaluation by a Norwegian government-funded research consortium, addresses many concerns that people have about the sector in Scotland. Our approach will be transformational.”

In simple terms, a closed containment farm viewed from shore appears very similar to a conventional open-net farm. “We surround and protect the net below the surface with a flexible, impermeable membrane, a specialist marine membrane which separates the farmed environment inside the membrane from the outside environment, stopping sea lice from getting in,” says Hawthorn, who adds that the impermeable membrane also prevents seals from seeing the fish, eliminating the need for anti-predator nets to keep them away. 

“That’s good for the environment and good for the fish. We pump deep water into the nets which is why we avoid the sea lice as they live in the top few metres and it also reduces the numbers of plankton and jellyfish getting into the farm. Pumping in deeper colder sea water means always having full salinity and is cleaner and much more stable in terms of its chemistry and temperature.

 “The membrane also acts as a settlement chamber: rather than going into the environment, faeces are captured at the bottom of the enclosure and can be pumped ashore, concentrated and used in green energy production, or as an ingredient in fertiliser for land farmers. The Loch Long development would be the first example in Scotland where marine waste is captured and used as a resource,” says Hawthorn. 

The company’s Beinn Reithe project on Loch Long in the Loch Lomond & The Trossachs National Park is its first proposed site. As with many developments, the company – a joint venture between Simply Blue Aquaculture and Golden Acre Foods – has found that obtaining permissions is frustratingly slow.

“We went through a process with the National Park’s planning team and ultimately, despite them initially being very encouraging and helping to find the best location for the development, the Park took a contrary view at the last minute.

‘‘The first project would represent an inward investment to Scotland of £35m.’’

“While we were obviously disappointed with that, we have appealed it to the Scottish Government because we think it’s important to get on and do things rather than just talking about doing them,” he says.  

The project has been “called in” by Scottish ministers for a final decision after that initial refusal by the National Park Board with the Scottish Government recognising that this first site is “strategically important”.

As well as addressing the issues and opportunities within Loch Lomond & The Trossachs National Park, the National Park Partnership Plan also sets out national priorities to achieve benefits for Scotland beyond the park’s boundaries.

This means a unified approach to managing and improving the condition of natural assets on a landscape scale and to promote, test and implement innovative solutions to rural issues that will widen the range of benefits that the national park’s environment can provide to Scotland’s people and visitors.  

As part of this initiative the company intends to establish an ‘open-door’ policy, inviting a wide range of stakeholders including academics, industry colleagues and community groups to learn from what it is doing. “We believe that by rolling this out further across the sector that we can get the industry to grow – but with less environmental impact,” Hawthorn says.

And Hawthorn is convinced this type of sustainable growth is crucial. Scottish salmon, he points out, is not only Scotland’s largest food export but the largest in the United Kingdom.  “Salmon consumption around the globe is growing and this is a real opportunity for Scotland to continue to be an important player in global food production.”

This has important implications for the country to which Hawthorn returned after gaining international experience in the farmed salmon sector after graduating with an MSc with distinction from the internationally recognised Institute of Aquaculture at Stirling University.

He smiles: “I’ve been fish farming since the 1980s in Scotland, in Canada, New Zealand, then back to Canada and returning to Scotland – with the benefit of having a very patient family who have come along with me on all these adventures, living in coastal communities. 

“So, for me, keeping this activity rooted in rural communities on our own west coast is extremely important. We enjoy an immensely competitive, natural advantage in our ocean, and we should use that to ensure we have our future economy rooted in productive, responsible industries such as this.”

Which, he believes, involves a wider vision for the industry: “Getting the site up and running at Loch Long will demonstrate its potential and then have other people adopt it – because there’s a stated ambition by the sector to double production by 2030 based on 2016 production levels.

“Production last year however was no higher than it was in 2016 so there’s been no progress made over the past five or six years in terms of growing the sector in Scotland. That strongly suggests we need to innovate and bring positive new approaches so that the industry can not only keep operating but positively thrive.”

He’s encouraged by support on several levels including MSPs such as Fergus Ewing, Angus Robertson, Pam Gosal and Jenni Minto. “We also have the support of bodies such as Sepa, Forestry and Land Scotland and NatureScot plus the local MP, councillors, the nearest community council and a cross section of local people and groups who all believe that it’s time to do something positive and make a change. 

“A range of environmental groups, including the Atlantic Salmon Trust, the Marine Conservation Society, the Scottish Wildlife Trust and the Sustainable Inshore Fisheries Trust also support using this technology because they recognise the benefits it can bring.”

Hawthorn stresses the need for swift action: if the project was to be approved in the first part of this year, he says it would still take some 18 months to build. “We would expect to have fish in the water sometime in 2025 or 2026 so it’s important that this project is approved quickly. If it isn’t, the next opportunity for this technology to come to Scotland may not be for four or five years,” he warns.

The company is planning a second project, Lurignish near Appin on Loch Linnhe, which is currently at the pre-planning phase and the company has so far held a total of five public consultations, though this site is several years away from commercial development and not likely to be operating until 2028.

“That would be the earliest before the Loch Linnhe proposal could be up and going if it were to get through the various stages of approval. That’s why it’s important for Scotland to grasp this opportunity for change that will address environmental concerns while improving fish health, welfare and survival,” he says. 

“So, my current focus is emphasising to the Scottish Parliament and government the importance of this technology beacause this is the quickest way to make a difference.

“And while people talk about being in a crisis, we hear less about them taking real action and making a difference – not just in food production but across the board. We need champions who want positive innovation and change to address climate and environmental concerns now, to make their voices heard. There is no time to lose. 

“We have a new technology in a crucial sector that’s proven and sustainable.  It can be adopted in Scotland – and we must get on with it.” 

This article is sponsored by Loch Long Salmon


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