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


Environmental Impacts

Criterion score: -5


Fish Health and Welfare

Criterion score: 1



Criterion score: 2


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.


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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