Canadian Farmed Salmon
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. 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. As a result, Canadian salmon farmers now use less than 30% 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.
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, new studies show that farmed salmon need only about 1 kg of feed for every kg of weight gained.
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
- Under the supervision of a veterinarian, all farm sites employ an integrated pest management plan, which outlines a multi-level approach to controlling sea lice.
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.
Why they’re environmentally sustainable…
Life cycle analysis (LCA) demonstrates that farmed salmon perform better than other food proteins in terms of key environmental impact measures:
Energy Use: the evidence indicates that the life-cycle energy intensity for farm-raised salmon is better than beef.
- GHG Emissions: GHG emissions for farm-raised salmon are lower than beef, poultry and pork.
- Water Use: Farm-raised salmon has consistently lower water use than other types of animal farming, using only a small fraction of the water compared to other species.
- Land Use: Farm-raised salmon requires much less land than used in the production of most other species.
All salmon farming companies in Canada are certified to one or more third-party certification program that assures consumers that they are purchasing high quality, sustainably produced salmon.