“I’ve never seen one. I don’t have the patience to stand there long enough!” says Hazel Wade of the wild Atlantic salmon in the Falls of Shin, the thundering cataracts in the Scottish Highlands up which the fish leap to return to their spawning ground every summer. Or rather, the falls up which salmon used to leap in their tens of thousands before overfishing, climate change and farming reduced their numbers such that to see just one, you’d have to stand there for a long time.
Once so abundant, they came in waves, their huge, iridescent bodies hurling themselves through the rainbow-flecked foam. Now, they’re an endangered species. “Fifty years ago, for every 100 smolts [young salmon] that went to sea, about 25-30 returned as adults. Today, the number is more like four,” reads one of the information boards at the Falls. Game fishing is still allowed, but any salmon caught must be returned; commercial salmon fishing has been banned in Scotland since 2002. In short, any Scottish salmon you’ve eaten in the past 12 years will have been farmed.
This is where Hazel Wade comes in – site manager for one of 12 farms that operate under the Loch Duart label, one of the only independent salmon farming companies in Scotland and a pioneer when it comes to more sustainable farming practices. I’ve come, by way of the Falls of the Shin, to meet her and the salmon she and her team oversee in Loch Laxford, off the northwest coast. It is bitter on the boat that takes us from their small office to the salmon pens, but the grey clouds are high in the sky, and as we set off Wade points out an eagle wheeling above.
The nearby estate has worked hard to restore eagle populations over the last decade, she explains, and have more recently turned their attention to wild sea trout and salmon, with a conservation project aimed at restoring their respective populations. “We support them in collecting data, lending our boats and helping them install kit,” she says. The hope is to track, understand and support their return to the area after a dramatic decline in both species in recent years.
Salmon pens
Though wild salmon populations continue to dwindle, the farmed fish are thriving inside Wade’s pens. “We stocked seven pens at the beginning of October, then transferred half of them last week [early June] to give them as much room as possible.” Each of Loch Duart’s sites typically has ten pens, with each pen containing around 30,000 fish – 300,000 in total. This sounds like a lot until you compare it with a large-scale industrial salmon farm which will have “three million fish, easily,” says their communications manager Adam Grey. He does not wish to speak ill of his competitors, and I’m here to see what Loch Duart do differently. However, it is clear from the research I’ve undertaken that such an intense concentration of fish is a problem on many levels – not least because, ironically, it is one of the factors contributing towards the wild salmon’s demise.
In conventional farms, the fish are densely packed, leading to lice infestations which can infect any wild salmon swimming past. These aren’t like head lice; they eat the fish’s flesh and can prove fatal. Scotland’s weather, not known for its clemency, has resulted in the pens breaking, allowing farmed salmon to escape and interbreed with their wild counterparts. That sounds delightfully Free Willy, but far from bolstering wild salmon populations, they compromise their genetic resilience. “Escaped salmon breeding with wild salmon significantly lowers the survival rates and survivability of wild fish,” says Matt Palmer, once a veterinary surgeon on an intensive Scottish salmon farm, now Campaign Manager at Wild Fish, a conservation charity dedicated to reversing the decline in wild fish populations.
Palmer and I speak some weeks prior to my trip to Loch Laxford about the concerns that continue to plague the more intensive salmon farms, despite concerted efforts by the industry to address them.
“Wild salmon populations have plummeted in the last 20 or 30 years,” he continues. Most farmed salmon in Scotland and Norway are from a limited gene pool and have been selectively bred for specific traits like growth rate, disease resistance and age of maturation; traits which help salmon farms turn a profit, but spell disaster for wild salmon embarking on a 2,000-mile round trip from Scotland to Greenland and back again. Equally concerning to Palmer and the growing number of chefs and consumers who are calling for an end to all salmon farming are the conditions on the farms themselves.
A fillet of Loch Duart salmon
In February this year, the Fish Health Inspectorate revealed that mortalities on Scottish salmon farms reached 17.4 million in 2023, exceeding those the year before. The majority of these came from two of Scotland’s largest salmon producers. Pesticides, antibiotics and other chemicals used to treat the lice and other diseases responsible for these mass mortalities have been known to drift along the coast and damage lobsters, crabs, mussels and other coastal wildlife; equally concerning has been the build-up of faecal matter and uneaten food below the salmon pens.
The Scottish Environment Agency has made concerted efforts in recent years to improve conditions across salmon farms, with some success. Antibiotic use has plummeted, and each new pen must meet strict criteria to limit the risk of escapees and the build-up of organic matter. Yet no farm or government agency has yet been able to address the biggest barrier to long-term sustainability, which is the amount of wild fish that must be caught and killed to feed the farmed salmon, around 2 to 3kg, producing just 1kg of salmon meat. Substituting a proportion of this with plants – as many organic salmon farms do – hasn’t helped much because of the environmental cost of growing, transporting and processing that into something that offers the nutrients required for pelagic fish, and it has resulted in fillets that have far lower levels of omega-3.
Which is partly why I’m at Loch Duart. I’ve not eaten salmon for two years on account of reading endless damning reports about the ethical and environmental issues dogging the industry. Many of these issues apply to livestock farming, of course – often to a far greater degree – but at least on land, I’ve been able to find farms adopting a regenerative approach; that is, not taking more out of the environment than they are putting back in. With salmon, I didn’t think this possible until Ben King, the founder of online fish market Pesky Fish, introduced Loch Duart as “the very first farmed salmon that we can qualify as regenerative. At Pesky the objective is to accelerate regenerative fishing. The term regenerative is overused, but we judge against three criteria, no matter what the species.”
“They must be net producers of fish; feed must come from certified abundant stocks, and there should not be lasting damage to the surrounding marine environment,” he explains. Against these criteria, every other salmon farm would fail miserably. “We worked with Loch Duart for a year and a bit in order to validate all the data, and that gave us confidence that they’ve moved away from a commoditised industrial process that delivers quantity to one that delivers quality. They have massively engaged with local fishing associations to measure stock levels of existing species and measured marine vegetation around the farm to ensure no signs of degradation.” By regularly leaving pens fallow for a year, they ensure the health of the seabed is restored, and they have systems in place to avoid a build-up of food and faecal matter. All this and more means “They produce 43% less carbon than the industrial standard,” says King. “They are not perfect – but in a murky environment, they are a single beacon.”
King urges me to go and see for myself – “Don’t just take my word for it!” – which brings me back to the boat on Loch Laxford. We pull up just as the salmon are about to be fed – “You can see them through the dark water,” says Wade – and as if on cue, an electric feeder starts scattering fish meal in a circular motion around the pen. “The fish meal is our big sustainability story this year,” Grey explains. After years of development, the industry created a feed that boasts both a low carbon footprint, a high proportion of marine content and a low Foraged (Wild) Fish Dependency Ratio (FFDR).
“FFDR quantifies the environmental impact of aquaculture feed and is calculated using the feed conversion ratio plus the inclusion level of forage (wild) fish marine ingredients in the feed and their yield ratio,” he explains. “We want to feed the fish as naturally as we can, which means a high marine diet. In the past, that meant taking too much wild fish from scarce resources – but we’ve managed to reduce our dependency on wild stocks by sourcing 51% of the marine content from industry trimmings from MSC-certified fisheries.” This makes their FFDR just 0.33: an industry-leading score, which makes for three times the industrial levels of omega-3 and means they qualify for the Label Rouge in France – “which as a measure of quality is super-impressive,” Gray says.
“It smells like what you used to feed your goldfish,” he concedes – but feeding here entails far more than flinging flakes into a fish tank. Behind the scenes, his colleague is monitoring a series of cameras to see how much feed is falling to the seabed. “We follow the feed down to make sure it’s getting picked up by the less dominant salmon as well as the dominant ones – so we start at the top, then check the cameras below the surface. The bottom camera will show any mortalities too, so it’s the first port of call for any issues. The wrasse is loving that camera,” he laughs. “See?”
He points and, sure enough, a funny, colourful fish is rivalling a minor celebrity for playing up to the camera. These are the cleaner fish – the chemical-free approach to managing lice infestations. They feed on salmon lice and supplementary feed and “they are not easy to come by,” Wade explains. One of the arguments against using wrasse is that they themselves must also be caught, with potential implications for the ecosystems that they are fished from. Loch Duart limits this by sourcing their wrasse solely from regulated wild fisheries and are at the forefront of researching the possibility of farming wrasse. Where the more intensive farms tend to cull the wrasse along with the salmon at the end of each harvest, for ease, Loch Duart is meticulous about removing the wrasse from the pen.
A salmon from the farm
“We believe we have the highest cleaner fish reuse rate in the global aquaculture industry,” says Gray. Sourcing wrasse from carefully regulated fisheries makes them “a huge investment for the company, and it makes sense to look after them correctly.” Were the salmon as tightly packed into their pens as is standard in the industry, this would be impossible to manage, but stocking density is another key distinguishing feature of Loch Duart. “We aim for 98.5% of water to 1.5% of fish. That is very low compared to most farms,” says Wade.
What they lost in quantity, they make up for in quality – and in a marked reduction in disease, the spread of which increases when fish are crammed in, just as it does through humans in a packed tube carriage. It means the fish have room to shoal and swim – not a given, as anyone who has seen undercover footage of intensive salmon farms will recall – and that they receive an industry-leading ratio of animal husbandry. The fish are health-checked at least twice a week. “We take ten fish out of each pen, anaesthetise them, and do a visual check for lice or gill issues,” says Gary. Any issues are swiftly addressed by transferring the pen to a freshwater bath, a closed pen on a boat, through which fresh water is pumped for four to six hours. “Any lice will come off, and any disease on the gills will clear without us having to use medicine, antibiotics or chemicals.”
Critics of this practice say physical handling stresses the salmon – something they try to reduce by choosing a time when the salmon haven’t eaten for a while, so are lacking in energy. This is true whenever they have to handle the fish: for breeding, moving them to different pens or culling. “If they aren’t trying to digest food whilst something is happening, they are less stressed,” Wade explains. Whilst she accepts that handling causes some stress, she points to the practice of catching wild salmon and then returning them to the river, something game fishermen pay handsomely to do year after year.
“That is stressing the fish.” There are issues which still need addressing – their packaging post-production is not recyclable, for example, and the endlessly adaptive seals still threaten to push and grab, or leap up and over into the nets – but they’re working on them, and hope the industry will follow their lead. “Fish farming is a huge industry, but as a small-scale business, we feel like a research lab for making fish farming better. That’s an exciting place to be.”
Her comments point to some of the complexities and contradictions inherent in salmon consumption in general. Humans in this part of the world have eaten salmon for centuries and in abundance. Even into the early 1990s, some netting stations were hauling in 5,000 wild salmon. They have been an integral part of the Scottish diet and culture for at least 2,000 years. A Burns Night menu without salmon in some capacity is impossible to conceive; likewise, the Scottish economy, which earns £760 million from farmed salmon each year.
At a time when the British diet lacks both nutritional value and self-sufficiency, it seems mad to reject a home-grown source of essential fatty acids and vitamins – and yet, for many, farmed salmon feels so different as to be irreconcilable with the legendary creature from which it takes its name. There is the genetics, of course, and the devastating crossover between the two, though Loch Duart is ahead of the game.
Loch Duart, Scotland
“Our brood stock can be traced back for a good 30 years, and they were originally taken from local rivers,” says Wade. Were any to escape, they would be almost indistinguishable from the wild salmon they might meet – though Loch Duart has never had an escapee, thanks to the strength and design of its nets and its meticulous maintenance and location. I have no doubt that Loch Duart is the most sustainable salmon farm in Scotland; yet as I watch these sleek silver bodies circulate their pens, something niggles. It’s not the quality of the feed or the carefully monitored quality of the water to which I’m invited, under a microscope, to observe. It’s not the harmless jellyfish bobbing under our feet or seagulls wheeling overhead – the nets protect against those.
It’s the principle of the thing. The Falls of Shin had reminded me of just how extraordinary the life cycle of wild salmon is, from the eggs buried in the banks of the river bed to the small fry which grow there for two to three years to the smolts that turn streamlined and silver in preparation. They travel two thousand miles to their feeding grounds in Greenland, growing from the size of a pencil to the size of a small child before returning home – and no one knows how they navigate their way there or back again.
From the open seas, they swim up the tidal estuary, where their ability to cope with fresh and saline water comes into play – then turn unerringly into the mouth of the river they came from. From there, they swim up, leaping waterfalls as they go and reabsorbing the fat they built up at sea. They stop eating in readiness to reproduce, and their skin loses its silver sheen. Famously, they die after spawning in the same place where they were born.
That humans can recreate this epic quest artificially and at scale is a feat, and Loch Duart does a tremendous job of replicating it as closely as possible. “Our broodstock – around 1,000 hens and 300 males – are at sea at the moment. When we bring them into the freshwater tanks in late September, we don’t do anything; we just wait for winter,” says Wade. They stop feeding within 48 hours of hitting the freshwater, as they would in the river, and as the temperature drops and the daylight changes, they naturally turn brown and produce eggs and milt. These, the team strip and transport to their hatcheries nearby, designed to replicate the river’s gravelly pits.
Once the young fry hatch and mature into smolts, they are returned from the hatcheries to the pens at sea. “We know when they are ready to go to the sea because they turn to swim with the current in the freshwater tanks; when they’re young, they sit into it.” At every point, the team ‘read’ the fish. “They tell you then they’re ready,” Wade explains.
Gray is right to point out that fish farming is something the public isn’t well-placed to understand because it is relatively new and always evolving. “The technology and skills in salmon farming are improving each year,” he points out, whereas land-based agriculture has been around for millennia. Perhaps there is a future in which Atlantic wild salmon populations are revived and can co-exist alongside farmed salmon, like bison restored to the plains of Europe – and if anyone can do it, Loch Duart can and will.
The more likely scenario is that the only salmon our grandchildren will know will be reared within the confines of a pen – and to have reduced this six-million-year-old species, once the king of fishes, to that is a damning indictment of modern consumption’s effect on the world.
