Fish Farms

6 Sep 2012
Read time: 10 min
Category: Archive

Of course, coastal communities aren’t the only victims in the destructive path of aquaculture — a path that widens each year as Westerners in particular eat more and more fish for its omega-3 and protein content. Many don’t realize it, but omega-3s and complete proteins are readily available in plant foods, without the deleterious health and environmental effects (see the articles by Tom Fisher, RN, and Dr. David John Carmos in this issue). One also has to consider the effect aquaculture has

on marine biodiversity, as wild fish are used to feed many species of farmed fish.

Wild fish populations are already in serious trouble from overfishing. A global collapse of all fished species is predicted by 2050, according to the UN, who estimate 30% of fish stocks have already collapsed. This problem is only exacerbated by fish farming, as it takes up to 20 pounds of wild-caught fish to produce one pound of farmed tuna. Even vegetarian fish species such as tilapia and carp are fed wild fish and fish oil.

Then there’s the issues of pollution (chemicals, pharmaceuticals, etc. in wastewater) and the welfare of the animals being farmed in filthy and cramped conditions.

It is clear the only ones who come out ahead in the world of modern aquaculture are the captains of the $70 billion/year industry (NOAA Aquaculture Program website, 2009). While the detrimental environmental effects of fish farming vary depending on the species being farmed and the methods being employed, one can be certain that more profit means less environmental stewardship. This is overwhelmingly evidenced in the case of shrimp farms, one of the most destructive forms of aquaculture.

Mangrove forests in Asia and Latin America are being cleared to make room for shrimp farms. These forests protect coastlines, providing food and shelter to countless wildlife and supplying multiple resources to impoverished coastal people who rely on them for daily sustenance. As shrimp farmers uproot mangrove forests and exploit their shrimp populations, they quickly move along for higher production yields, destroying more mangroves and displacing more wildlife along the way.

Most fish farms, just like their terrestrial cousins that raise pigs and cows and chickens, are interested in profits above all else. As with sickly factory farmed land animals, farmed fish are fed antibiotics to protect profits. Toxic by-products and cancer-causing contaminants have been found in factory farmed salmon. Dyes are also used to make the grayish flesh of farmed salmon look pink (like wild salmon). These contaminants aren’t just bad news for those who eat the fish, but for the environment and the wild fish that occupy it.

Farmed fish are prone to parasites such as sea lice, which have become a serious problem in Northern Europe and British Columbia. Before the advent of aquaculture, sea lice were only reported on adult salmon. Now younger salmon are severely affected. As salmon eggs hatch and the juvenile fish emerge from the rivers and make their way to the ocean, they pass fish farms, which are typically located on migratory routes. The crowds of captive fish in these farms creates a hotbed for sea lice, which attach themselves to the passing wild salmon. Since juvenile pink and chum salmon are smaller than AAA batteries and may not have developed scales yet, these fish can be killed by a single louse. Also a threat to adult salmon, the feeding activity of sea lice can cause serious fin damage, skin erosion, constant bleeding, and deep open wounds, creating a pathway for other pathogens.

As fewer salmon make it to sea each year, their numbers dwindle. Wild salmon collapses are predicted in the next decade in some affected areas.

Fish are forced to live in crowded conditions on farms, creating an excess of fish waste and unconsumed feed in the water, which pollutes the surrounding waters. Living in such close proximity gives rise to disease and infection, which is usually responded to with antibiotics, further polluting the surrounding environment. The fish themselves can pollute the environment as many escape when net-pens are damaged by storms. Nearly three million salmon escape from farms each year. These escapees can often outnumber wild species, causing many complications.

The introduction of foreign marine species — both exotic species and domestic forms of native species — is a growing problem. Since an overwhelming number of farmed fish escape their pens, aquaculture is the primary way that foreign species are introduced to new areas. This disrupts local ecosystems and threatens native species in many ways: escapees can carry diseases and parasites that are lethal to local wild species, indigenous species are displaced as they have to compete with newcomers for habitat and food, the long-term survival and evolution of wild species is hampered when foreign species breed with wild stock and dilute the gene pool.

Onshore fish farming is another form of aquaculture that has gained recent popularity. These operations consist of giant swimming pools filled with fish in places like Ohio. Onshore aquaculture creates untold amounts of toxic waste and this kind of farming is very cruel to fish, removing them from any semblance of a natural environment. These confined fish are still tainted with environmental toxins, as they are fed wild fish and fish oil. Onshore farms also utilize the inefficient “more wild fish in for less farmed fish out” practice. Regulation of these farms is at least as lax as offshore aquaculture, and those who have visited these overcrowded pools of fish say the water is almost black with feces.

Wild fish aren’t the only species affected by factory farms. High concentrations of prey animals and waste food inherent to aquaculture farms attract everything from wild seals, seabirds and sharks to mollusks and crustaceans. To protect their farms from predation by native animals, many aquaculture operators illegally kill would-be predators. Some farmers kill wild animals legally, as is the case with Canadian farmers who are obliged by law to shoot and kill sea lions (Fisheries and Oceans Canada, “2001 Marine Mammal Predator Control”). Many salmon farmers also use Acoustic Harassment Devices (AHDs) to deter predators. These machines, targeted specifically against seals, emit a high-pitched noise (198 decibels — equivalent to the sound of a jet engine at take-off) that causes physical pain in the animal’s ears. Unfortunately, AHDs also harm dolphins, porpoises and whales. Studies in Canada found that the intense pitch scared off harbor porpoises and killer whales at a range of up to 10 kilometers.

As our appetite for fish grows, so does our dependency on imported fish grown on foreign farms, largely in Asia and Latin America. These regions have potentially unsafe production practices and use chemicals and additives that have been banned in the U.S. It is important to note that just because a practice or additive would be illegal to implement in the U.S. does not mean the sale of the end product is discouraged. In fact, the United States alone imports approximately 10.7 billion pounds of farmed sea animals annually. Beyond the substances that fish farmers add to farmed fish, there is also the concern of environmental toxins such as mercury, BPA and dioxins.

Most countries, including the U.S., require labels to identify farmed and dyed salmon, but many big-name retailers have been sued in recent years for failing to comply with the laws. Monitoring of domestic fish farms is poorly regulated and the overwhelming majority (80% in 2009) of farmed fish consumed in the United States is from foreign farms. Not only is there no oversight on the foreign farms — there is virtually no oversight when the fish arrives in the U.S. The Food and Drug Administration tested about 0.1% (one-tenth of one percent) of all imported sea animal products for drug residues during 2009. Only 2% of total sea animal imports are inspected at all (Oceana, 2011).

As with any packaged food, consumers must know what to look for when reading fish labels. A 2011 Consumer Reports exposé revealed grossly negligent fish labeling practices. Over one-fifth of the 190 pieces of sea animals bought at retail stores and restaurants in New York, New Jersey and Connecticut were not what they claimed to be. The most notable of the misidentified fish was tilefish being labeled as grouper. On average, tilefish contains three times the mercury found in grouper, which is why the FDA advises pregnant women to avoid tilefish completely.

Beyond human error (and potential deception, as some experts say mislabeling is a way to “launder” illegal fish into the sea animal market), the labeling system itself is flawed. Consider these loopholes in the USDA’s labeling laws:

  • “Processed” sea animals are exempt, leaving more than 50% sold in the U.S. without labels.
  • 90% of fish sellers, such as wholesale markets, are exempt.
  • No enforcement mechanism exists and violators face paltry fines.
  • Another parallel between labeling of land and sea animals is greenwashing — the practice of making a product appear eco-friendly when it is not. A study at the University of Victoria determined the “eco-label” found on some farmed fish is no assurance that sustainable methods were used in production. In fact, some were worse than conventional fish farms when it came to protecting the oceans. As with labels that proclaim “free range” or “cage free,” “wild caught” labels on sea animals should be looked at with scrutiny, as many are applied to farmed fish.

    Some proponents of aquaculture claim closed containment fish farms hold promise for sustainable sea animal production, but the jury is still out, as these operations still require more wild fish in for less farmed fish out. One thing is for sure — the most powerful method for change in the fish industry is voting with our dollars. Many experts say there is no such thing as sustainable fishing these days, but for those of us who feel they really must eat aquatic animals, wild freshwater fish caught with a hook and line is still the way to go.

    Whether we are vegetarians (and remember, fish are not vegetables) or omnivores, more sustainable fishing practices benefit us all. Reading labels (with scrutiny) and asking questions can be helpful in making educated decisions. The less farmed fish we all buy, the more conscious practices will abound.

    Share article: