Canadian Farmed Salmon
Atlantic salmon (Salmo salar) is the predominate species farmed in Canada. In British Columbia, two species of Pacific salmon – Chinook (Oncorhynchus tshawytscha) and Coho (Oncorhynchus kisutch) – are also farmed.
Where they’re farmed…
Salmon are farmed in British Columbia, New Brunswick, Newfoundland & Labrador, Nova Scotia. British Columbia and New Brunswick are the predominant producers of Canadian farmed salmon. Farmed salmon is British Columbia’s largest agricultural export product - and the largest crop in the New Brunswick agri-food sector.
How they’re farmed…
To produce the highest quality farmed salmon, the very best adult female salmon are selected each year as breeding stock. Each female produces about 10,000 eggs, which are fertilized and incubated in the temperature-controlled tanks of a freshwater hatchery. Once they hatch, the baby salmon are nurtured at the hatchery for up to 18 months. At this age, the young salmon then begin to smoltify – a natural process of physiological change that enables them to live in salt water. Once this process is complete, the smolts – now about 12cm long and weighing 100g – are transferred from the hatchery to net pens floating in the ocean. Over the next 18 months, the smolts grow into adult salmon with a harvest weight of about 4.5kg.
What they eat…
Salmon are fed nutrient-dense, dry pellets consisting of natural products. Using ingredients that are tested for quality and purity, feed manufacturers tailor-make feeds to suit the exact dietary requirements of the salmon at each stage of their life cycle. Currently, the main ingredients are fish meal, fish oil and plant proteins (such as soy). The fish meal and oil are primarily made from forage fish that are too small and bony to be used for human consumption. Canadian feed manufacturers are developing new feeds that are increasingly replacing some of the fish-based ingredients in salmon feed with ingredients from sustainable sources such as vegetables – yet still provide high quality, nutritious farmed salmon.
Several feed formulations now include less than 30% fish meal and oil, and Canadian producers are leading the way in terms of utilizing low-meal diets for salmon culture. In some salmon feeds, the use of alternative ingredients has allowed a 50% reduction in the use of fish meal and fish oil, with no significant reduction in the amount of heart-healthy omega-3 fatty acids in the fish. Canadian salmon farmers use an average of 30 percent fish meal and oil in their feed. That means only 0.4 kg of wild fish meal and oil are needed to grow 1 kg of farmed salmon. Where possible, the alternative feed ingredients are sourced locally.
Feed manufacturers also add essential vitamins, minerals and carotenoids to the salmon feed. Carotenoids are important antioxidants that help to ensure the optimal health of the fish. Carotenoids also give farmed salmon its characteristic pink/orange coloration.
Farmed salmon convert feed into their muscles, fat and bones very efficiently. While a cow needs about 7 kg of feed for every kg of weight that it gains, farmed salmon require only about 1.5 kg of feed. New studies show that by further improving their feed, salmon will soon need less than 1 kg of feed for every kg of weight gained.
How they stay healthy…
The welfare of farmed salmon is the primary factor that determines farm management practices. Salmon farmers ensure that their farms are located in well-flushed waters that meet a variety of specific criteria (e.g. temperature, salinity and depth) necessary for salmon to thrive. They also ensure that their staff have a detailed knowledge of salmon husbandry – and that they are attentive to the day to day living conditions of the fish.
With the active support of veterinarians and scientists, salmon farmers undertake many preventative measures to ensure the health of their salmon from hatching to harvest. The health of all breeding stock is carefully assessed before they are used as a source of eggs. To provide further protection, salmon farmers seek to prevent disease-causing fish pathogens from entering the hatcheries.
Only healthy smolts are transferred to the ocean net pens. However, once the smolts begin their life in the ocean, they may encounter naturally occurring pathogenic organisms. Therefore, before being transported to the net pens, smolts are often individually injected with a vaccine to protect them against known pathogens. These vaccinations greatly reduce the incidence of disease in the net pens – and, as a result, have significantly reduced the use of antibiotics and other therapeutants. In fact, farmed salmon commonly grow to maturity without any use of antibiotics during their lives. Antibiotic use on salmon farms is now far lower than that of any other agricultural animal producing industry in the world.
Despite all of the preventative measures, some salmon do occasionally become ill. A veterinarian will then examine the fish and determine the appropriate action to be taken. As with all farm animals, the veterinarian may sometimes decide that the illness requires antibiotic treatment - and will then prescribe a registered antibiotic that is approved by the Veterinary Drug Directorate of Health Canada. Prescribed antibiotic treatments are always in full accordance with the treatment protocol permitted by the Veterinary Drug Directorate.
Following antibiotic use, a strictly regulated withdrawal period and testing program ensures that no harvesting of the treated salmon occurs until the medication has cleared from their system. Salmon farms have the longest regulated antibiotic withdrawal period of any agricultural sector in the world.
Market ready Canadian farmed salmon is routinely inspected by the Canadian Food Inspection Agency (and, for US exports, the Food and Drug Administration) to ensure that it meets government standards for the absence of antibiotic residue.
Why they’re environmentally sustainable…
Since pristine seawater is essential for the production of healthy, high quality salmon, each salmon farm must function in harmony with nature. A salmon farm’s economic viability could be significantly impacted by reduction in environmental quality.
Farm Siting Practices
All approvals for salmon farms in Canada are subject to an intensive environmental review according to both federal and provincial legislation, including the Canadian Environmental Assessment Act (CEAA).
Salmon farms can only be sited in areas where water currents provide optimal conditions for fish health and environmental sustainability.
To prevent salmon stocks from escaping and to limit interaction between wild and farmed species, salmon farmers in Canada follow rigorous enforced standards and guidelines to ensure that farmed salmon remain on site.
Salmon farmers are constantly innovating and improving their systems, and in recent years stock loss through breaches in containment have been virtually eliminated.
To limit nutrient pollution, salmon farmers employ state-of-the art feed monitoring systems that use real-time technology, such as underwater cameras and sensors, to detect uneaten feed and adjust feed delivery to the appetite of the salmon.
Research conducted by the Department of Fisheries and Oceans confirms that the area affected by wastes is generally limited to the area directly beneath the net pen, or in the immediate vicinity. In most cases, the area returns to its natural state within months of harvesting the fish.
Sea lice are naturally occurring parasites that feed on the skin and mucous of both wild and farmed salmon. Sea lice cannot live in fresh water - therefore all smolts are free of sea lice before they enter the net pens. However, since sea lice are able to pass through the netting of the pens, farmed salmon may become infected by the sea lice carried by wild salmon in the surrounding water. Since this parasite cannot be eliminated from wild salmon, salmon farmers have developed management practices that reduce the likelihood of infection. These practices include:
- Selecting farm sites with good flushing and water current
- Production sites are emptied of all fish for periods of time (fallowed). Without a host, the sea lice population declines
- Only farmed salmon born in a single year are present at each farm site – this prevents older farmed salmon (who may have received the parasite from the wild salmon) from transferring it to incoming smolts
- Employing bay management systems where hydrographic conditions severely restrict wild-farmed fish interactions and reduce the possibility of year-class carry-over
The effectiveness of these management practices is supported by many scientific studies that suggest that salmon farms have little impact on the sea lice levels that naturally occur on wild salmon. For example:
- A recent scientific study found that wild salmon in an area where there were no farms had as many sea lice as wild salmon in an area where salmon farming occurs.
- A second recent scientific study found exceptionally high numbers of wild salmon in an area containing 16 active salmon farms – and concluded that wild salmon populations and farmed Atlantic salmon could coexist successfully.
- A 2007 BC Pacific Salmon Forum press release stated that “all the field researchers noted that over 80 percent of the wild salmon smolts migrating out of [a salmon farming area] in the spring of 2007 had no lice whatsoever.”
- Other scientific studies have shown that young pink salmon mount an effective immune response to sea lice infection. This immune response causes the lice to be shed from the salmon – and thereby protects the young salmon from illness or death due to sea lice infection.
The Atlantic Salmon Federation, a New Brunswick-based conservation organization dedicated to saving wild Atlantic salmon, confirms that sea lice from farms in the Bay of Fundy are not infecting wild salmon.
For further information on sea lice, see CAIA’s sea lice fact sheet (English version) or
fact sheet (French version).
Wild Salmon Conservation
Canadian salmon farmers recognize the need to protect wild salmon populations - and are proud to partner in the wild salmon conservation effort. They support a range of wild salmon enhancement projects and education initiatives through the provision of direct financial contributions, modern hatchery equipment, high quality salmon feed and technical support to wild salmon enhancement hatcheries and organizations.
Did you know…
Farmed salmon has become the second most popular seafood consumed in the US.
The Canada Food Guide recommends eating at least two portions of fatty fish like salmon per week. Farmed salmon is a rich natural source of protein, DHA omega-3 fatty acids, vitamin D, and many other minerals and vitamins so essential for human health and nutrition. It ranks among the lowest animal foods in terms of content cholesterol and saturated fats.
Atlantic Canada Fish Farmers Association: www.atlanticfishfarmers.com
British Columbia Salmon Farmers Association: www.salmonfarmers.org
Aquaculture Association of Nova Scotia: www.aansonline.ca
North Atlantic Aquaculture Council: northatlanticaquaculture.com
Aquaculture Association of Canada: www.aquacultureassociation.ca
Newfoundland Aquaculture Industry Association: www.naia.ca
Cooke Aquaculture: www.cookeaqua.com
Marine Harvest Canada: www.marineharvest.com/Canada
Mainstream Canada: www.mainstream-group.com
Pacific Salmon Forum: www.pacificsalmonforum.ca