Salmon, Atlantic (Farmed)

Salmo salar

Method of production — Farmed
Production country — UK
Production method — Open net pen
Picture of Salmon, Atlantic (Farmed)

Sustainability rating three info

Sustainability overview

Salmon are farmed in open net pens in the sea. Producing fish in open systems can cause environmental impacts such as: impacts of chemical and sea lice treatment usage; nutrient and organic waste deposition; outbreaks of disease; impacts on wild salmonids by transmission of sea lice, and escapes from farms. Salmon are carnivorous fish and rely on wild capture fisheries to produce their feed, MCS would like to see all these fish certified as sustainably managed. Due to the ongoing nature of as yet unresolved environmental impacts of salmon farming MCS is advocating a halt in industry expansion until these can be resolved.

Feed Resources

Criterion Score: 2

The ingredients that make up feed for Scottish farmed salmon are responsibly sourced. In recent years the amount of fish contained in the diets has reduced and been replaced with vegetable proteins and oils.


Environmental Impacts

Criterion Score: -5

In un-certified farmed Scottish salmon there are concerns about the use of chemicals in terms of failed benthic sampling at some farms. These chemicals are sea lice treatments that can have an effect on crustacea species such as lobsters. Due to the elevated sea lice numbers at farms there is a risk of transfer to wild salmonid species - trout and salmon. Escapes are another issue of concern, there are periodic large escape events but regular trickle escapes of small number of fish. The interbreeding of farmed fish with wild fish and the intercompetition between them is of concern. Seals can be lethally controlled under license to protect farmed salmon from attacks. Wild wrasse species are caught to be used as cleaner fish to control sea lice, a percentage of these are coming from poorly managed wild stocks.


Fish Health and Welfare

Criterion Score: 1

Welfare standards including humane slaughter are covered by Freedom Foods standards to which most of the industry in Scotland are certified



Criterion Score: 2

The National Marine Plan for Scotland is yet to be operational, this will hopefully integrate aquaculture into wider marine planning. Regulations are in place for all of the issues of environmental concerns, however given the failure of some farms in terms of chemical use this can only be classed as being partially effective. 90 % of the industry is certified to the industry’s own Code of Good Practice.


Production method

Open net pen

Salmon are farmed in open net pens in the sea. These are floating cages suspended in the sea and held in place by moorings underneath the cages.


Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below. Click on a name to show the sustainable options available.

Anchovy, anchovies
Arctic char
Herring or sild
Salmon, Atlantic (Farmed)
Salmon, Chinook, King Salmon
Salmon, Chum, Keta, Calico or Dog salmon
Salmon, Coho , Silver, White
Salmon, Pink, Spring , humpback
Salmon, Sockeye , Red Salmon, Bluebacks, Redfish
Trout, Rainbow
Tuna, albacore
Tuna, bigeye
Tuna, skipjack
Tuna, yellowfin


Salmon are termed “anadromous”, meaning during their lifecycle they move between fresh and marine waters; salmon farming attempts to mirror this lifecycle. Broodstock fish are moved to freshwater for spawning, where the eggs are also fertilised and hatched. The hatched fish (called fry) are also kept in freshwater and fed pellets manufactured from fish meal. At about 18 months the fish (now called smolts) are transferred to seawater cages where growth continues until market size is reached, usually at about 2 years.


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