Sustainable salmon farming: a caterer's guide to informed choices and better menus
Salmon has long been a staple on catering menus. It’s popular with diners, versatile for chefs, and promoted as a healthy, high-protein choice. For many years, it has also been marketed as a sustainable alternative to wild-caught fish, but the reality behind modern salmon farming is far more complex. As demand continues to grow, so too does scrutiny of the environmental, ethical, and social impacts of farmed salmon, from the Scottish Highlands to remote areas of Chile.
For caterers, procurement teams, and organisations committed to responsible sourcing, it’s increasingly important to understand what lies behind the label. allmanhall’s role is to support clients in making sustainable, evidence-based decisions, with salmon farming an area where that support is more relevant than ever.
From fish farm to fork: why salmon sourcing matters
Farmed Scottish salmon is the UK’s largest global food export, valued at £645 million a year. The industry provides 2,500 direct jobs in rural and island communities and is estimated to support around 10,000 more in the wider supply chain. However, these benefits come with environmental costs, particularly in how the fish are farmed.
Environmental impacts in Scotland: what’s at stake
Much of the UK’s salmon is produced in open-net pens (floating cages in the sea) which can result in significant ecological challenges.
Waste and water pollution result hen salmon faeces and uneaten feed fall directly through the nets into the surrounding water, settle on the seabed and create low-oxygen “anoxic” zones. This reduces biodiversity and harms benthic ecosystems – anything associated with or occurring on the bottom of a body of water (the animals and plants that live on or in the bottom are known as the benthos).
Nutrient enrichment is also a key problem. Nitrogen and phosphorus from fish farming can fuel excessive algal growth, and when this occurs, oxygen is depleted and toxins can be released. This disrupts marine ecosystems and threatens wildlife, including wild fish, shellfish, and invertebrates.
High stocking densities in salmon farming also facilitate disease and parasite transmission such as sea lice, which can transfer to wild salmon. This has become a major concern for conservationists and ecological groups across Scotland. Worryingly, recent reports indicate that around 40% of salmon in Scottish farms die before harvest, due to stress, disease, parasites, and environmental conditions.
Even salmon marketed as organic or responsibly farmed are typically raised in similar open-net systems, which has led to accusations of greenwashing.
Did you know? Some Scottish farms report mortality rates above 40%. Asking suppliers about welfare standards and survival rates can help you make more informed choices..
The need for reform: is change coming fast enough?
Given all of these problems, there has been a lot of frustration regarding the relatively slow rates of legislative change in salmon farming. A 2024 Scottish parliamentary inquiry called for better regulation, including weekly transparent reporting of lice levels, chemical use, and mortality rates. It also recommended powers to close high-risk sites. However, progress has been slow, and implementation remains inconsistent.
Beyond the UK: what Chile’s salmon tells us
While UK menus may highlight Scottish salmon, much of that consumed in Europe and North America comes from Chile, which is the world’s second largest producer. Between 1990 and 2017, the industry increased production by almost 3,000%, with more than 750,000 tonnes exported to more than 80 countries. This rapid expansion has led to serious sustainability concerns.
These include:
- The highest aquaculture fatality rate globally, with 83 workers dying between 2013 and 2025. By comparison, Norway recorded just three deaths in 34 years.
- Annual use of around 560 tonnes of antibiotics, much of which enters the ocean. Norway uses virtually no antibiotics in salmon farming. As much as 70-80% of these antibiotics are thought to enter the marine environment, contributing to pollution and antimicrobial resistance.
- Reports of declining wild species and polluted waterways, impacting small-scale fishers and Indigenous communities. A decline has been reported in species such as sea urchins and mussels due to pollution from salmon farms.
With the EU now among the largest markets for Chilean salmon, these impacts have global relevance.
Caterer tip: Ask where your salmon is sourced. If from Chile, probe further on antibiotics, worker welfare, and environmental impact.
Feeding the problem: what salmon eat and why it matters
Salmon are carnivorous and require high-protein, omega-3-rich diets made largely from wild-caught fish such as anchovies and sardines. This creates pressure on global fish stocks, which are already under strain.
Studies suggest that if these wild fish were instead directed to human consumption, global seafood availability could increase significantly, with reduced environmental damage.
Reducing reliance on fishmeal not only lowers pressure on wild stocks but can also significantly reduce the carbon footprint of farmed salmon. Although progress is being made through the development of insect-based feeds, algae-based oils, and the use of fish processing by-products, widespread adoption is still limited.
Can you trust sustainability labels?
Certification labels are often used in catering procurement to signal ethical or sustainable sourcing. However, their efficacy has come under increasing scrutiny in recent years.
The Marine Stewardship Council (MSC) ‘blue tick’ is the most well-renowned seafood certification scheme. However, it’s been criticised for:
- Certifying fisheries where the underlying science is uncertain.
- Using assessors (CABs) paid directly by the fisheries they evaluate, creating potential conflicts of interest.
- Granting certification to high-impact methods such as bottom trawling.
- Focusing heavily on stock sustainability while downplaying biodiversity and habitat impacts.
- Failing to consider labour conditions in its criteria.
In fact, a leaked WWF report described systemic flaws within the scheme and suggested financial incentives may influence certification decisions. While MSC remains influential, its limitations mean it should not be relied upon as a sole indicator of sustainability.
allmanhall support clients in understanding what certifications truly mean, helping them navigate labels like MSC.
Practical steps for caterers: making salmon more sustainable
To meet sustainability and cost targets, caterers can take these evidence-based actions:
- Source wisely – prioritise salmon from Norway or certified UK farms with low mortality rates and good welfare records.
- Rethink the menu by substituting mussels, trout, or responsibly sourced whitefish, or introducing plant-rich seafood alternatives.
- Balance cost and ethics – use seasonal menu planning to control spend and reduce high-impact species across the week without compromising variety.
- Monitoring regulatory changes in Scotland and internationally.
- Encourage supplier transparency on feed sources, antibiotic use, sea lice management, and chemical treatments.
allmanhall help caterers manage menu planning in ways that protect margins while supporting sustainability goals. For example, we can help by reducing reliance on high-impact species and promoting lower-impact options that still meet nutritional and culinary requirements.
A need for greater transparency and reform
Salmon farming is not as environmentally damaging as some types of farming, but the scale and intensity of production in regions like Scotland and Chile presents major challenges.
Caterers can help drive positive change through:
- More transparent procurement
- Stronger supplier questioning
- Menu diversification
- Engagement with responsible producers
allmanhall are here to support sustainable food strategies with insight, tools, and evidence. Contact us to explore how we can support your sustainable sourcing ambitions with insight, data, and hands-on expertise.