We’ve all been there. You’re in the freezer aisle of the supermarket trying to understand the different labels on seafood products. You know the oceans are in trouble and you’re trying to do the right thing, but the information is confusing and seemingly contradictory.
A package of salmon fillets has a smiling dolphin logo on the back. Another, a less smiling bright blue fish logo. You grab your smartphone and open the sustainable seafood app your friend told you about, only to be more confused by the traffic light ratings. In the end, just choose any product that the label guarantees is sustainable.
Understanding salmon sustainability
Salmon is one of the most consumed seafood in the world. It is a rich source of proteins, essential micronutrients and fatty acids. But with so many different products on the shelves, it’s difficult to know which ones harm the environment and fish stocks the most.
Both wild-caught and farmed salmon can be sustainable, but determining a fillet’s environmental impact is not simple. Both can present significant social and environmental problems. Wild-caught salmon may be overfished or sourced from vulnerable fish populations. But while salmon aquaculture can reduce pressure on wild stocks, it is not a panacea.
Farmed salmon producers often face scrutiny for overcrowding, parasites and pollution, and escapees from open-net pens fear they endanger local wild populations. The fishmeal used to feed farmed salmon presents other problems, as it often comes from wild-caught fish that are not always consumed at sustainable levels.
These challenges are expected to be exacerbated by climate change: higher water temperatures and reduced rainfall could allow pathogens to grow and increase the susceptibility of fish populations to disease.
There are many certification schemes, eco-labels, ratings and guides to signal salmon sustainability. For wild-caught salmon, the Marine Stewardship Council provides the gold standard, ensuring it comes from fisheries managed according to strict environmental standards. For farmed salmon, a mark of approval from the Aquaculture Stewardship Council is considered the most complete certification, indicating responsible aquaculture practices.
One of us (Laurence Wainwright) researched eco-labels for five years, finding that these two certification schemes are currently the most scientifically sound and evidence-based standards for the sustainability of seafood products – including salmon.
Other seafood sustainability regimes offer some guarantees of sustainability, but are often not as stringent. Schemes for farmed salmon, such as the Soil Association’s organic standard, have recently faced criticism for having standards that are seen by some as not going far enough – or potentially even misleading customers by certifying some Scottish salmon farms as organic.
To a consumer, an “organic” label generally means that a product was grown from organic foods and produced without the use of chemical pesticides or antibiotics. Farmed salmon can be organic if it is raised and fed correctly.
A spokesperson for the Soil Association said: “Organic farms must follow strict rules to minimize impacts on the environment and animal welfare, and when problems occur they must demonstrate that they are taking steps to use the organic logo.” The Soil Association’s aquaculture standards are currently under review following a 60-day consultation, and an update to its standards is expected to be carried out in late 2024.
According to fish conservation charity WildFish, some sustainability badges in salmon aquaculture can mask details of unregulated salmon supply chains – with certifications rarely being lost, even when conditions are breached. According to its 2023 report, some UK farms were allowed to use wild fish for food and use toxic chemicals to control parasites, without losing their organic certification. This is controversial: such ambiguity and lack of transparency only harms the salmon aquaculture industry.
When it comes to wild-caught salmon, it is our strong opinion that it is never legitimate under any circumstances to call it organic. This is not only misleading, but it also defies scientific evidence and undermines the meaning of the term organic.
Which salmon should you buy?
When purchasing salmon or ordering it at a restaurant, look for important information on the labels or ask the staff about the origin of the fish.
How and where was it captured or cultivated? Anyone can be sustainable, but the devil is in the details.
If grown, what food was it fed – and where did that food come from? Food should come from a sustainable source of fish, and perhaps even certified.
If it is caught in the wild, are there minimum bycatch associated with it?
What species of salmon is it? Whether Atlantic, chinook, sockeye, pink, coho or chum, sustainability depends on a variety of factors, so there is no hard and fast rule. But there are better and worse options: this guide from Seafood Watch is very helpful.
What eco-labels do you have? Marine Stewardship Council and Aquaculture Stewardship Council certifications are the best.
The salmon scale
While it’s best to choose locally sourced fish whenever possible, many salmon-loving populations live far from salmon production hotspots. Sushi salmon in Japan, for example, may have traveled 17,000 km from Norwegian or Chilean farms. And around 52% of the emissions from producing 1 kilogram of farmed salmon in Norway come from air transport for consumption in China.
The need to mitigate the carbon footprint of salmon production will only increase as the world steps up decarbonization efforts. As the world population increases, pressure on already overexploited wild salmon stocks is expected to intensify.
Salmon farming or aquaculture currently bridges this gap between supply and demand, representing 70% of the salmon available for consumption. As the fastest growing food production system, the salmon farming industry is expected to reach a value of US$37 billion (£29 billion) globally by 2027.
We need to fundamentally change our relationship with seafood if we want to preserve this wonderful natural food resource. We don’t have to stop eating salmon, but we do have to make smarter decisions, both at the fish counter and in the seafood supply chains.
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