Debating Cultures: Wild or Farmed?

There are two sides to every story. Both sides of the farmed vs. wild salmon debate carry benefits and detriments.

By Erica Commisso

Photos By Vicky Lam

fish tail

What Is Good About Farmed Salmon?

The Canadian Aquaculture Industries Alliance says that farmed salmon, specifically, is “one of the best sources of DHA and EPA Omega-3 fatty acids.” They speak to its health benefits, and The British Columbia Salmon Farmers Association speaks to the benefits for the marine environment. They “strive to meet the requirements of ‘Gold Standard’ environmental programs, having minimal impact on nature while relieving pressure on wild fish stocks,” and boast a 95% survival rate within their population. They argue that all of the viruses that pose a threat to the farmed salmon population are also present in the Pacific Ocean, and are therefore also threatening to wild salmon. Those viruses are also not a threat to human health.

“One of the best sources of DHA and EPA Omega-3 fatty acids.”

Going further, the salmon farming industry has a hand in developing smolt vaccines, designed to protect the farmed fish from viruses found in the saltwater ocean. Those vaccines are given to all fish before they leave the hatchery, and reduce the need for antibiotics. The level of antibiotics used has steadily decreased in the past 15 years.

Farming salmon also eliminates the possibility of the fish being contaminated with a parasite called sea lice, which can be found naturally on many wild marine fish. Farm-raised salmon are lice-free when entering ocean pens, but face infestation when they assimilate. Farmers have practices to mitigate and manage the presence of sea lice.

Finally, the Canadian economy, specifically in British Columbia, also heavily relies on salmon farming to generate revenue. It is the highest-valued agricultural export in the province and therefore creates stable employment in communities along the western coastline.

What Is Wrong With Farmed Salmon?

Unlike wild fish, whose life cycle entails the natural function of a normal immune system that is selected in the age-old quest for home and natural survival-of-the-fittest, farmed salmon suffer from other types of parasite infections (fungi, intestinal worms and other health risks found in all types of animal agriculture), pathogens, and protozoa (such as Dinoflagellates), and require the aforementioned vaccines and vet-administered antibiotics to fight them. And, as the farming gets more intensive, the stress on animal immune systems heightens, making them less able to fight parasites and diseases when released into the ocean. Farmed fish are, until their release, kept in concentrations never seen in the wild — for example, 50,000 fish could be kept in a 2-acre (8,100 m2) area.

Farmed salmon produce waste concentrations never experienced in the wild, and this density of bio-waste changes the acidity of the water, polluting it. There is also considerable damage to the land and water environment from penned farm salmon when they escape — and they escape by the millions every year. The invasion of these “fugitive” fish alter marine environments, coastal rivers, and associated food chains around the world. They become a permanent environmental pollution. Mass escapes of farmed salmon result in interbreeding and competition with wild salmon for food, habitat, and mates. Male farmed fish are more aggressive than male wild fish, and therefore begin breeding with female wild fish. The cross-breeding results in a decreased population of organic, wild fish, causing the species to become endangered. Escaped fish also transmit their inevitable diseases and parasites to wild salmon, and threaten to establish viable colonies that could not only push wild salmon to their limit but also threaten closely related species, such as steelhead salmon and sea trout.

“In 2005, aquaculture represented 40% of the 157.5 million tons of seafood that was produced, making it a critical part of our world’s food source.”

IS IT WORTH IT?

The cost of food inputs per unit of fish weight is higher than in extensive animal farming, especially because of the high cost of fish feed. For salmon, feed must contain a high level of protein (which comes from wild species, especially anchovies), and a balanced amino acid composition. Higher protein level requirements are a consequence of the higher food conversion efficiency (FCR—kg of feed per kg of animal produced) of aquatic animals. Fish such as salmon have FCR’s in the range of 1.1 kilograms of feed per kilogram of salmon, whereas chickens, for comparison, are in the 2.5 kilograms of feed per kilogram of chicken range.

Clearly, it is expensive to raise farmed salmon. On the other end of the spectrum, though, it employs hundreds of thousands of farmers across the country and generates substantial income nationally. Global returns for fish farming (recorded by the FAO in 2008) totalled 33.8 million tonnes, worth about $60 billion USD.

In 2005, aquaculture represented 40% of the 157.5 million tons of seafood that was produced, making it a critical part of our world’s food source. Because of this rise in aquaculture, there has been a rise in the per capita availability of seafood globally within the last few decades. It is hard to imagine how the world might get along without it. It is just unclear which breed — wild or farmed — will be more common.