Choosing wild salmon over farmed isn’t just better for your taste buds, it’s also better for your health and for our coastal ecosystems. Read on for more information about why you should go wild!
The Healthier Choice
- A 2010 investigative report by CTV News found that wild salmon is considerably more nutritious and carried fewer toxins than farmed salmon. Samples taken from wild-caught Pacific salmon were found to contain as much as three times more Vitamin A and eight times more Vitamin D than farmed Atlantic salmon and to be a safer source of Omega-3 fatty acids.
- A 2004 study published in the journal Science found that farmed salmon contained as much as seven times the amount of polychlorinated biphenyls, or PCBs, as wild-caught salmon. PCBs are a family of chemicals that were banned from consumer products in the 1970’s after evidence emerged that they caused cancer in humans.
Factory Farms of the Sea
- Net-pen salmon farms are, essentially, floating CAFO’s (Concentrated Animal Feeding Operations). A typical BC salmon farm consists of 10 to 30 net-pens, each 12 or 15 meters square and containing around 20,000 salmon.
- Just like land-based CAFO’s, net-pen salmon farms generate a lot of waste. A typical salmon farming operation of 200,000 fish produces as much nitrogen as 20,000 people, as much phosphorous as 25,000 people, and an amount of feces equivalent to a city of 65,000 people . All of this waste flows out of the pens directly into the marine environment, smothering habitat and causing lethal algal blooms.
- Aside from spawning events, salmon do not typically gather in large densities. Being so densely crowded into the net-pens places a significant amount of stress on the salmon, which triggers the release of hormones in the fish that actively suppress their immune systems, making them more susceptible to diseases
Deadly Disease and Mass Mortality
- The high population density of the net-pens also make salmon farms an ideal breeding ground for parasites. Farmed salmon are often infested by sea-lice, further contributing to the spread of disease and infecting wild salmon that swim past the net-pens. In BC alone, mass mortality events due to disease on salmon farms produce as much as 20,000 tons of excess waste each year in the form of dead fish.
- Infectious Salmon Anemia (ISA) is a contagious viral disease that was first detected on Norwegian salmon farms in 1984. Since then it has spread to salmon farms in Scotland, Latin America, the United States, and Atlantic Canada. A 2007 outbreak in Chile resulted in the destruction of as much as 70% of the country’s farmed salmon. Alarmingly, ISA has recently been detected in North Pacific waters.
- Infectious Hematopoietic Necrosis (IHN) is another virus of serious concern which has been linked to salmon farms. IHN can infect both Atlantic and Pacific salmon species, and is transmitted through water, movement of fish, or contact with contaminated waste or equipment. Salmon fry and fingerlings are most susceptible to this virus, causing mortality rates as high as 100%.
- Furunculosis is a highly contagious bacterial disease that causes lesions and haemorrhaging of fish tissues. Lethal to salmonids, it is caused by Aeromonas salmonicida bacteria and is spread by fish-to-fish contact or through animal vectors, such as seabirds and sea lice.
- Bacterial Kidney Disease (BKD) is another bacterial infection that results in high mortality among salmon. BKD causes nodules to form on the fish’s kidneys and other organs, such as the liver, spleen, and heart. It is spread either vertically, through infected sperm or eggs, or horizontally, through contact with other infected fish.
- While the majority of the bacteria present in salmon do not pose any major risk to human health, E.coli, Salmonella, and Serratia are a serious threat to both humans and salmon alike. Heavy reliance on antibiotics and other pharmaceutical drugs to combat diseases on fish farms has been shown to promote antibiotic resistance in these bacteria, thus contributing to a major human health concern.
Pesticides and Petrochemical Dyes
- In an effort to control sea lice infestations, BC salmon farms treat their fish feed with the pesticide emamectin benzoate, more commonly referred to as SLICE. However, heavy use of SLICE on salmon farms has resulted in sea lice developing a resistance to this drug.
- While there has been nothing to indicate SLICE resistance in sea lice on BC salmon farms, resistance in sea lice on Canada’s Atlantic coast has caused salmon farm operators to resort to bath treatments using deltamethrin (Alphamax), azamethiphos (Salmosan), and hydrogen peroxide (Interox Paramove) to combat sea lice infestations. After treatment, the pesticide-laden water is simply released into the marine environment.
- SLICE, Alphamax, and Salmosan are all non-target treatments, meaning that they are not only toxic to sea lice, but also to other shelled invertebrates and crustaceans, such as shrimp, prawns, crabs, and lobsters.
- The flesh of wild salmon is pinkish-red in colour because the bodies of the tiny creatures that the fish prey upon contain carotenoids. Salmon cannot synthesize these chemicals themselves, so the diet of farmed salmon must be supplemented, often with petrochemical dyes, to give their flesh that appealing pinkish hue; a practice referred to in the industry as “colour finishing”. Without this treatment, farmed salmon flesh would be an unappetizing pale grey colour.
- The tens of thousands of salmon packed together in net-pen salmon farms represent an irresistible smorgasbord for marine mammals whose natural prey include wild salmon. As a result, hundreds of seals, sea-lions, and porpoises drown each year when they become entangled in net pens and other debris from salmon farms.
- Other marine mammals that approach too close to salmon farms are shot on sight by “predator control” workers. According to DFO reports, between 1999 and 2010, salmon farmers in BC legally shot or otherwise killed 1935 harbour seals, 738 California sea lions, and 202 Steller sea lions, a species listed under the federal Species at Risk Act (SARA) as being ‘of special concern’.
- Escapes of invasive, non-native Atlantic salmon from net-pen farms into wild Pacific salmon habitat poses a significant threat to native fish species, either through competition for habitat and prey or the transmission of farmed salmon diseases and pathogens.
- A 2000 study published in Conservation Biology found feral Atlantic salmon swimming in more than 80 wild salmon spawing streams in British Columbia, with juveniles discovered at three locations, suggesting that escaped Atlantic salmon are surviving and breeding in our Pacific waters.