Salmon farming: is it a fishy situation?

Kaylynn Wohl, Environment Editor

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Along the beautiful mountain-surrounded coast of Norway, bright blue waters house thousands of the favorite “pink” fish in which omega-3 fatty acids are most commonly found. In these waters are not free-range happy and healthy salmon; instead, hundreds of thousands of these fish are bred within huge underwater floating net cages which are placed side by side, as depicted by farmedanddangerous.org.

In contrast to commercialized fishing, which is the catching of wild fish, aquaculture is defined as the cultivation of fish in controlled environments. The mass farming of salmon, formally called salmon aquaculture, threatens not only the environment and other fish in the ocean but the consumer’s health as well. As a consumer of salmon, it is important to know where your food is derived and what goes into the process of production, including the chemicals added.

Origins of Aquaculture

Aquaculture is an ancient practice dating as far back as 4,000 years ago. According to a website by the Food and Agriculture Organization of the United Nations (FOA), aquaculturist Herminio R. Rabana states the practice began by a Chinese aquaculturist with the farming of the common carp around the years 2000 to 1000 B.C. Later, in 475 B.C., Fan Li wrote the book “The Classic of Fish Culture,” the earliest novel to “record and describe the structure of ponds, the method of propagation of the common carp and the growth of fry.” From then on, during the reign of the Tang Dynasty, the cultivation of carp expanded to other pond culture species including the silver carp, the mud carp, the grass carp and the big-head carp. As worldly trade began to inflate, aquaculture expanded as the global demand for fisheries grew exponentially.

The aquaculture of salmon began in Norway during the 1960s. From there, production vastly expanded to other oceans across the globe to places such as Japan, Chile, Canada and eventually the United States. British Columbia’s fish production has significantly expanded since the early 1980s and is the home to the majority of the world’s salmon farms. According to Master’s thesis by marine biologist Ashley Park, as of 2007, there were 10 major companies that owned 147 caged farms in BC, of which 90 percent were owned by multinational Norwegian companies.

Disease Outbreaks and Sea Lice

Occurring naturally amongst wild fish, sea lice are small marine parasites vaguely similar to the lice humans often get. According to farmedanddangerous.org, they attach themselves to the skin, fins and/or gills of various fish as their way of feeding, causing “serious fin damage, skin erosion, constant bleeding, and deep open wounds creating a pathway for other pathogens.” These parasites are one of the biggest threats to salmon farms. Because there are hundreds of thousands of salmon in small cages year round, sea lice thrive in these areas and infect and even kill their host fish.

Furthermore, due to containment within a net cage, it is common for the salmon to escape their farms to enter the wild waters. In other words, “It is also possible for sea lice to carry diseases between farmed and wild salmon,” as stated on farmedanddangerous.org. Runaway salmon threaten the lives of other fish as they spread various diseases.

In attempt to eliminate the sea lice epidemic, farmers use chemicals and pesticides in the waters, including the use of chemical additives in the fish’s food. Farmedanddangerous.org also states, “Emamectin benzoate [(EMB)] (marketed as SLICE®) is the preferred chemical for sea lice control in Canada,” but unfortunately there is very little scientific research done on its biological and ecological effects. Furthermore, “up until June 2009 SLICE was only available to fish farmers through the Emergency Drug Release Program, which allows the use of non-approved drugs when recommended by veterinarians for emergency situations.” The Food and Drug Administration has categorized EMB as an unapproved drug in the US, “however… on average, this chemical is being used at least once during the production of every farmed salmon from BC—with over 80 percent of this product going to the US market.”

Environmental Impacts

Salmon farming in permeable cages is one of the most environmentally dangerous aspects of aquaculture. According to marine biologist Park, “Open-net systems allow uneaten feed and cultured fish fecal material to distribute to the surrounding environment.” Additionally, roughly 17 percent of their feed goes uneaten and contaminates the ocean floor, resulting in other species in the water consuming the chemically altered food that is intended for salmon consumption only. Their uneaten feed is often “contaminated with drugs, antibiotics, and heavy metals (zinc, copper and cadmium) that accumulates in sediment and organisms in proximity to salmon farms.” Not only that, but that accumulated sediment eliminates much of the oxygen in the water, resulting in the death of many deeper sea creatures.

Park elaborates, “Producing salmon this way… can allow many nutrient and chemical inputs as well as pathogens to disperse freely to the marine environment. A typical single farm in BC operates between six and 24 cages with an average of 35,000-50,000 fish per cage.” This high density of salmon production thus requires masses of feed and chemical, which results in the heavy contamination of the surrounding waters.

Mariah Byars is a marine biologist major who spent her first semester of college at the University of Hawaii at Manoa and is now a PVCC student. Her passion for aquatic life shows when she discusses the negative impact salmon aquaculture has on other marine species, including coral. “[Aquaculture] allows for all the pesticides, chemicals and hormones to leak out through the nets and into the oceans. This kills ecosystems and can also be a cause of the enormous coral bleaching epidemic that is occurring right now,” she said. Chemicals from the farms are essentially killing coral, which are mainly found near the equator; Chile, also located near the equator, is the second largest salmon producer and contributes to this epidemic.

According to an article by Anthony Esposito of Reuters, the coastal waters of Chile are contaminated with bacteria called SRS, which infects and kills fish. Due to the inability to produce an effective vaccine, farmers multiply their antibiotic use in order to fight the epidemic; just two years ago, the industry used 1.2 million pounds of antibiotics. As a consumer of salmon, it is important to know that these chemical induced species are frequently purchased and sold by big companies like Costco, which “used to buy 90 percent of the 600,000 pounds of salmon fillet it needs per week from Chile.” Norway, the world’s largest salmon producer, uses far less antibiotics in its farms: a little over two thousand pounds during the year 2013.

Why Salmon Aquaculture is Considered Beneficial

Although there are countless negative environmental impacts on salmon aquaculture, there are some considerable benefits to the industry. Similar to the creation of factories during the Industrial Revolution, salmon aquaculture provides the economic benefit of the ability to produce more fish for more revenue. However, Odeh Sweiss, a sophomore working towards an animal behavior major at Arizona State University, challenges this idea. He stated, “I believe that [salmon’s] role in the food chain as prey to keystone predators is more important. The farming of them is strictly commercial and provides no significant natural benefits.”

Owen Taylor is a former Alaskan resident who worked in Bristol Bay, “home of the largest sustainable Sockeye Salmon run in the world.” Due to spending frequent amounts of his time traveling, he was only able to provide his fishery expertise via email. One benefit to salmon aquaculture that he pointed out was to aid the decrease of overfishing. Taylor states, “Washington, Oregon and California have had serious overfishing problems and even had fish populations dwindle to unfishable levels.” He also considers the fact that in today’s society “we continue to trash and poison the oceans, making it harder for natural runs to thrive and survive… [aquaculture] can keep alive runs that may otherwise disappear to over fishing or habitat destruction.”

As we continue to destroy our aquatic ecosystem and many natural habitats, aquaculture ironically proposes the possibility to continue to produce the fish in controlled areas if and when their natural home no longer exists.

2 Comments

2 Responses to “Salmon farming: is it a fishy situation?”

  1. Dallas Weaver Ph.D. on December 5th, 2016 6:21 pm

    I suggest that the readers use google.scholar.com as a search engine on this stuff. The activists have been playing a false propaganda game of this subject along with the commercial fishermen for decades. There is millions of dollar at stake, so truth takes a back seat.

    This is how you get insane statements like: “roughly 17 percent of their feed goes uneaten”. When feed cost is your largest expense, wasting even !% is unacceptable, This is why the automated feed system look for excess feed and decrease the feed rate automatically.

    The very thought that chemicals in the northern waters which take almost 10,000 years to reach the equatorial area are causing coral bleaching is a pure fabrication.

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  2. JAMES HORNER on December 8th, 2016 10:27 am

    The deadly disease transfer between farmed and wild salmon should be enough to shift this to contained land base facilities. The biggest problem here in British Columbia is our schools of wild salmon fry are attracted to the night lights and easy pellet food as they migrate past. The smart farmed fish hover at the nets edge waiting for a real meal to enter.

    [Reply]

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Salmon farming: is it a fishy situation?