Monday, November 25, 2013

Salmon Farming... A Very Fishy Business

I know it makes me a bad Italian, but I hate seafood. It looks gross, it smells gross... if I ever had to eat sushi it would be like my version of Fear Factor. But despite this, I do like salmon. And with salmon, it is especially important to know where it comes from. I've stressed the importance of knowing where your food comes from before, but with salmon, if you don't know the right kind to eat, you may be supporting an industry that's seriously impacting aquatic environments, not to mention the wrong kind of salmon isn't even that healthy.

The kind of salmon you want to be eating is wild salmon. This salmon comes from the Pacific Ocean and other water bodies in the Pacific Northwest. It is fished in a sustainable manner and is really healthy for you. It's got omega-3 fatty acid, amino acids and high quality protein, and vitamins and minerals like zinc and vitamin E. What I really want to talk about is the salmon you want to avoid... farmed salmon. You will often see it on menus as "Atlantic" salmon, because it sounds wild; like it came from the Atlantic Ocean. However, wild Atlantic salmon are an endangered species, and not allowed to be fished in the United States. When you see "Atlantic," it means it was farmed. Which doesn't sound terrible, right? Actually salmon farming is not a sustainable practice. It is damaging to the environment and to the quality of the fish. (By the way, salmon can be farmed in the Pacific as well... you have to make sure it is wild salmon, not just called "Pacific" salmon). These salmon live in cages with thousands of other fish. They can escape and compete with wild populations of fish for resources. According to the Fisheries Reserve Services of Scotland, since the introduction of salmon farming in the Highlands, populations of wild sea-trout have declined. This could also be due in part to the transfer of sea lice from farmed fish to wild fish. Sea lice are small copepods (very small crustaceans) that parasitize fish. Normally they are not a problem because they are killed once a fish enters fresh water. But farmed salmon never enter fresh water. They are confined to a cage where the sea lice population can grow and grow. When wild fish pass these farms, they can be hit with huge numbers of sea lice, which can kill them before they make it to fresh water. This can be especially dangerous to young salmon. And sea lice can transfer disease from salmon farms to wild Atlantic salmon and other fish like brown trout and rainbow trout as well. One such disease transmitted by the sea louse is infectious salmon anemia, a viral disease that attacks fish red blood cells. Research in the past has shown uncertainty as to the impact of sea lice on wild fish, but an increasing number of studies are finding they are in fact harming wild fish populations.
sea lice on a young salmon

So how do fish farms try to combat sea lice? Pesticides, of course! In Canadian salmon farms, a chemical called emamectin benzoate, marketed as SLICE, is used. There is a lack of research on it, so the effects are largely unknown, but it has been shown to persist in the salmon's tissues and the environment. Usually that is not a good sign. Chemicals that persist in body tissues typically cause health problems, like DDT, polychlorinated biphenyls (PCBs), and methylmercury. Emamectin benzoate has also been shown to disrupt the growth of other crustaceans like crabs and shrimp. The label on a pesticide marketed as Proclaim, which is also emamectin benzoate, states, “This pesticide is toxic to fish, birds, mammals, and aquatic invertebrates. Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark. Do not contaminate water when cleaning equipment or disposing of equipment wash water.” But this is being used to treat salmon?! Although the FDA has not approved its use on fish destined for human consumption, it is not banned in other countries, and that fish is sold in the US market. So when you eat Atlantic salmon, you may be ingesting emamectin benzoate... In Canada there used to be a 68 day waiting period between the last application of the pesticide and harvest of the fish, but it was waved when the pesticide became approved for commercial use (it used to only be available for emergency use by veterinary approval). So now salmon can go to market right away with higher pesticide levels.

Pesticides aren't the only chemical added to salmon farms. The flesh of wild salmon is red-pink due to their natural diet which includes krill and shrimp (the krill and shrimp eat algae that produce red carotenoids. It's the same reason flamingos are pink!). Because farmed salmon are fed a diet lacking these things, their flesh is actually grey in color. So why does it still appear pink? They are fed an artificial dye to make them more attractive to consumers. One of these dyes has been linked to crystal formation on the human retina, although the amount you get from consuming farmed salmon is considered safe. Still weird! Farmed salmon are also given antibiotics to prevent disease. This leads to antibiotic-resistant bacteria which can harm other marine life and even humans. In a report commissioned by the World Wildlife Fund (who I do not completely trust... they apparently get a lot of funding from big oil) a group of scientists concluded that “antibiotic-resistant organisms in the marine environment will, in turn, pass their antibiotic resistance genes to other bacteria, including human and animal pathogens.” Farmed salmon also contain higher amounts of PCBs, dioxins, and other pollutants due to bioaccumulation. This means these pollutants accumulate up the food chain into the salmon. Smaller fish (like sandeels, Norwegian pout, and capelin) are ground up and incorporated into their diet, each of which contain some amount of contamination. Because the salmon are being fed these same fish over and over, the concentration of pollutants is higher than in wild salmon. Based on cancer risk from the chemicals that may be in farmed salmon, the US EPA advises that in North America, people should not consume more than one serving every two and a half months.

a dead sea lion caught in a salmon net cage
The salmon feed used at these farms raises more problems than just bioaccumulation. Taking these small fish from the ocean leaves less food for large wild fish and marine animals like cod, mackerel, herring, sea birds, wild salmon, and sea-trout.  It takes about 3 pounds of these little fish to produce one pound of salmon, making it an unsustainable practice.Cod in particular have been hit hard because they were over-fished, and the depletion of their small prey fish added to the problem. Another environmental problem that arises from salmon farms is algal blooms. When large amounts of salmon are kept in close quarters, their waste accumulates in a confined area. This overloads the area with nutrients, which allows algae to grow out of control. As the algae is growing, it is also dying, and microorganisms feed off the dead algae. This uses up much of the oxygen in the water, which fish need to breathe. This process is called eutrophication, and it can kill the salmon and surrounding wildlife quickly. In September of 2007, Marine Harvest Canada had 227 tons of salmon die to algal blooms at a farm in British Columbia. A process that intrinsically has this much waste is not a good one! There is another really sad effect of salmon farming... marine mammal deaths. Animals like seals and dolphins are attracted to these farms. They can become entangled in the net cages and drown, or they are intentionally shot! Salmon farms can get a license to shoot them if they feel they are a threat to their salmon stock. The Canada Department of Fisheries and Oceans posted a count of mammals killed or drowned during a period of 2011. 141 California sea lions were deliberately shot, 37 harbour seals were shot or drowned, and 2 Steller sea lions were shot (which is great because they are listed as a "special concern" under Canada's federal Species at Risk Act). And keep in mind that is just a period of 2011; a matter of months. Make sure to watch the video below. It really drives home the effects of salmon farming on marine mammals. Spoiler alert/warning... it's pretty sad.

Well I think I've covered a good amount of the environmental concerns associated with salmon farming. Let's talk about why farmed salmon is a less healthy choice than wild salmon as well. I've already addressed why farmed salmon contain higher pesticide and chemical levels. But they also contain less nutrients. Their fish feed includes soy and wheat byproducts, which they can not digest as they are carnivores. This leads to a fish with less beneficial nutrients for you (See the chart below). The feed also includes feather meal; ground up feathers from poultry farms that still have blood and meat attached. I just thought that was gross. The more vegetable products in a farmed fish's diet, the less omega-3's they have. There is really no way to tell what your farmed salmon was fed when you go to the seafood market or order it at a restaurant. They also have more fat because they do not have to search for food, swim more than the length of their cage, or evade predators. This makes the meat flabby and less appetizing than wild salmon. You can tell the difference by looking at the meat. More fat means more places for chemicals to accumulate too. Persistent, organic chemicals often are "lipophilic" (fat-loving) and accumulate in the fat. If there is less fat to store the chemicals, they will be excreted from the salmon's body faster.

Salmon Nutritional Content
     Wild Salmon   Farmed Salmon
   Vitamin A154 I.U.40 I.U.
Vitamin D533 I.U.60 I.U.
Fat Content2.5%13%
PCBs5 parts/billion27 parts/billion
Sample size: 100 grams. Source: CTV British Columbia/SGS Labs

Wild salmon, on the left, is richer in color and the white fat lines
are thinner. The farmed salmon on the right has thicker fat lines and
is lighter pink because its color is artificial.
salmon tank system
So what can you do to make sure you're not supporting the salmon farming industry? Make sure you do not buy it or order it at a restaurant! This applies to sushi bars as well. If you see salmon on a menu and it does not specify where it is from, ASK! Remember, Atlantic means farmed too. Wild salmon may be more expensive, but it's really worth it. It tastes better, is healthier, and does not cause the deaths of other marine animals. When you go to the seafood market, look at the salmon. Even if it says wild or Pacific salmon, it may not be. Sometimes markets will try to trick customers because they can make more money from wild salmon. Look at the fat lines. If they are thick like in the picture above, it might be farmed. Also, fresh wild salmon is only available from May to August due to fishing laws and the salmon's life cycle. If you see it being sold fresh off season, there's a good chance it's actually farmed. You can buy it frozen anytime though. I found a website that gives you the locations of where you can buy a particular type of wild salmon; Copper River salmon. It's particularly good fresh. This other website will give you a list of some restaurants that are wild salmon supporters. Look for the Marine Stewardship Council symbol on salmon at fish markets. It means it came from a sustainable source. Shop at health food stores, which are more likely to be environmentally friendly in the first place, like Whole Foods. You can also follow the chart below from the Monterey Bay Aquarium to help you find the right kind of salmon. When you go to purchase salmon, use it to talk to the fish monger. They should be able to tell you where it came from. You may notice in the chart where it talks about salmon farmed in tank systems. This actually is a more sustainable way to farm salmon. They are raised in tanks where they are not exposed to the environment and causing disease and pollution or attracting seals and other marine mammals. Because they are not exposed to the environment they do not acquire sea lice and don't need heavy amounts of antibiotics. This type of aquaculture (fish farming) is already being used with trout, tilapia, and a small percentage of salmon and is effective in reducing the impact on the environment. Unfortunately the salmon industry is reluctant to change. But making the change could save them money... their fish will not escape, they don't have to buy lots of chemicals and pesticides, their fish will not be killed by algal blooms and disease, and they can grow to full size six months faster. Although the quality of the fish may not be as good as wild, it could be a sustainable alternative that is cheaper for consumers.

Atlantic SalmonAvoid: Avoid these products for now. These fish come from sources that are overfished or fished or farmed in ways that harm the environment.Farmed Salmon, SakeWorldwideFarmed
Atlantic SalmonGood Alternative: These are good alternatives to the best choices column. There are some concerns with how they are fished or farmed – or with the health of their habitats due to other human impacts.Verlasso (R)ChileFarmed
Coho SalmonGood Alternative: These are good alternatives to the best choices column. There are some concerns with how they are fished or farmed – or with the health of their habitats due to other human impacts.Sake, SilverBritish ColumbiaWild-caught
Coho SalmonBest Choice: These fish are abundant, well managed and fished or farmed in environmentally friendly ways.Sake, SilverU.S.Farmed in Tank Systems
SalmonBest Choice: These fish are abundant, well managed and fished or farmed in environmentally friendly ways.Chinook, Coho, Chum, Keta, King, Pink, Red, Silver, Sockeye, SakeAlaskaDrift Gillnet, Purse Seine, Troll
SalmonGood Alternative: These are good alternatives to the best choices column. There are some concerns with how they are fished or farmed – or with the health of their habitats due to other human impacts.Chinook, Coho, Chum, Keta, King, Pink, Red, Silver, Sockeye, SakeCalifornia, Oregon, WashingtonDrift Gillnet, Purse Seine, Troll
SalmonGood Alternative: These are good alternatives to the best choices column. There are some concerns with how they are fished or farmed – or with the health of their habitats due to other human impacts.Pink, SockeyeFraser River, Washington,Reefnet
SalmonBest Choice: These fish are abundant, well managed and fished or farmed in environmentally friendly ways.SockeyeFraser River (early Summer-run), WashingtonReefnet
Salmon RoeBest Choice: These fish are abundant, well managed and fished or farmed in environmentally friendly ways.IkuraAlaskaDrift Gillnet, Purse Seine, Troll

And educate yourself and others! This part is really important. When consumers put pressure on an industry, it can change things. Share this article with your friends, family, and coworkers. I did days of research to make sure I got the facts straight. One website that was very helpful was that of the Coastal Alliance for Aquaculture Reform. It is a good place to get more information on the subject of salmon farming. You can even sign up to get the latest information on salmon farming. Keep yourself informed. Tell restaurants that serve net caged, farmed salmon that you would prefer if it were wild, and why. Or write them letters. If enough of their customers express this, they will make the switch. If  salmon farming industries realize that people do not want salmon that causes environmental pollution, competes with native fish, causes the death of marine animals, and is full of chemicals, they will make the switch to sustainable practices like tank farming. A positive change could be coming, but it requires your support!

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