Articles Magazine

Something Fishy? Aquaculture and the Environment


By Jody McCutcheon

Think that fish is the last ‘wild food’, harvested by ‘salty dogs’ in enormous ships? You may be surprised.

While some fish is still caught in the wild (with varying levels of damage done to the environment, depending on the method), we here at Eluxe would like to pull back the curtain on the growing practice of fish-farming, a.k.a. aquaculture. See for yourself exactly what goes into the industrial production of seafood, and then decide for yourself whether you want to eat it.

Seafood surprise, anyone?

Fish is perceived as a low-fat, heart-healthy protein source, and as such, demand for it has skyrocketed. In just five decades, average yearly per-person seafood consumption has risen worldwide by 70%, from 22 pounds to over 37 pounds, largely thanks to high-protein diet trends like Atkins; the global spread in popularity of sushi, and increased wealth allowing more people to spend money on meat and fish.

However, over that same time, Atlantic salmon have been fished to the brink of extinction, while according to the United Nations, upwards of 90% of large fish like tuna and marlin have been fished out of sustainability, and 32% of all wild fishery stocks have been overexploited. Several scientific reports now suggest the threat of extinction for marine life is at an “unprecedented” level, in part due to overfishing.


Aquaculture: Pros and Cons

Enter aquaculture to bridge the gap between voracious demand and unsustainable supply. A practice that began thousands of years ago in Asia has evolved into a $78 billion industry, with almost half of the seafood we eat coming from aquaculture. In the last few decades, in fact, aquaculture has become the fastest-growing method of food production. The UN estimates the industry has grown 600% in twenty years, to the point where the UN and US Department of Agriculture agree that farmed-fish production has now surpassed beef production worldwide.

One benefit of aquaculture is it can be less energy-intensive than land-based farming. Compared to land animals, fish are more efficient at converting feed to mass. Farmed Atlantic salmon are said to be most efficient, with a feed conversion ratio (FCR) close to 1:1, although that’s at the lower end of the spectrum compared to tilapia and catfish, both of which have FCR’s around 2:1. To compare, poultry’s FCR is roughly 2.5:1, while that of beef cattle is over 6:1. Less energy-intensive doesn’t mean more eco-friendly, though, as we’ll soon see.

For consumers, farmed fish provides a cheap alternative to wild fish, but they aren’t quite the same as their wild cousins. Due to a relatively sedentary lifestyle, farmed salmon tend to contain higher fat and lower protein levels, as well as lower percentages of omega-3 fatty acids and a less favourable ratio of omega-3 to omega-6 fatty acids, which mitigates omega 3’s cardiovascular benefits. And awful truth be told, farmed salmon fillets usually are usually a dull grey until chemically dyed pink.

And while farmed fish don’t contain high levels of ocean pollutants like many wild fish do—especially those living in industrial areas like North America’s Great Lakes—they almost always do contain various antibiotics, hormones and pesticides used in the farming process. Plus, farmed fish are usually crowded into their pens or ponds, creating fertile breeding grounds for diseases like infectious salmon anemia and parasites like sea lice—hence the use of antibiotics and pesticides.


Food Industry Lies

Impassive and duplicitous, the industrial agricultural that’s raping the planet’s land has now infiltrated our oceans. If aquaculture’s primary purpose is, as they claim,  to relieve pressure on the world’s wild fisheries, then why are wild stocks being depleted to feed farmed fish?

Farmed Atlantic salmon may have an ideal FCR of 1:1 (or thereabouts), but that just means it takes one pound of wild fish to produce one pound of farmed salmon. Yes, high-protein fishmeal is made of wild, low-on-the-food-chain, pelagic (open-ocean) fish. As much as 4.5 kilograms of pelagic fish go into a single kilogram of fishmeal. For fish with higher FCR’s, the whole skewed dynamic of feeding farmed fish with wild represents a constant overdraft on the ocean bank. This practice steals essential food sources from higher-on-the-food-chain marine life, which further skews the ecosystem. Overall, about 37% of the global seafood catch is used for feed, up from a mere 7.7% back in 1948. Under current trends, demand for fishmeal will exceed supply by around 2050.

In addition, although aquaculturalists claim the contamination of their farms is contained within their ponds, the truth is that industrial scale aquaculture destroys coastal habitats when waste, disease, antibiotics and pests are flushed out of farming ponds into local waters, where they infiltrate wild populations. In fact, waste from fish farms can oversaturate coastal waters with nutrients, creating dead zones that suffocate marine life. A poorly run farm of 200,000 salmon can pollute the coastal environment with amounts of nitrogen and phosphorus similar to that in the sewage of a town of 20,000. Even more alarming, the antibiotics being released are creating antibiotic-resistant pathogens that wreak havoc on farmed and wild fishery stocks alike.

Another concern is the potential escape into local waters of exotic, possibly genetically modified species that may eventually replace indigenous species. Massachussetts-based company AquaBounty, for example, is bioengineering fish to grow faster, an advantage that would help them outcompete fellow fish. But according to Time magazine, it is very easy and common for farmed fish to escape into the wild, thus just one GMO fish could do irreparable damage to a species.

And how many times has “bad seafood” caused food poisoning? More often than you might think. Due to lax physical inspection of seafood imports, fish can contain chemical residue from farming treatments, including potential carcinogens like the fungicide malachite green and the antibiotic nitrofurans, and even human feces. To offer an idea of how lax import inspections can be, understand that Japan physically inspected between 12 and 21% of its seafood imports, based on numbers gathered between 2004 and 2009. The stricter European Union, meanwhile, inspects between 20 and 50% of its seafood imports. The US gets the worst deal, though. While the nation imports over 90% of its seafood, the US Food and Drug Administration’s underfunded inspection program inspects less than 2% of it. That’s a lot of potential “food poisoning.”


What We’ve Learned

In a nutshell:

–Farmed fish isn’t as healthy as wild, and doesn’t deliver as many nutrients either

–There’s a danger of farmed or even genetically modified fish escaping into the wild and contaminating wild stock

Farms don’t solve issues of increased demand. The Jevons Paradox states that as production methods grow more efficient, demand for resources actually increases – so as aquaculture makes fish production increasingly efficient, and fish become more widely available and less expensive, demand increases across the board. This drives more fishing, which hurts wild populations. Thus, despite what fish farmers claim, fish farming cranks up the pressure on already-depleted populations of wild fish around the world.

The Solution May Be Simple

Despite risks of food poisoning, ingesting pesticide, and even worse, highly toxic mercury,  demand for big commercial fish like swordfish and tuna doesn’t seem to be decreasing, but people would be better off—economically and environmentally—by eating fish lower in the food chain, i.e., those with a more efficient FCR, which include:

  • Trout (freshwater)
  • Haddock
  • Whitefish
  • Anchovies
  • Perch
  • Squid
  • Mullet
  • Scallops
  • Sardines
  • Domestic crabs

Also, some species are better adapted for aquaculture. Farming barramundi, for example, is more efficient than farming salmon or cod, since barramundi requires less protein in feed than what it ultimately yields, thus producing a net protein gain.

With the huge demand for seafood and the need to preserve wild fisheries, fish farming seems to be the best solution. The billion-dollar question, then, is how to make aquaculture more efficient and healthy and less polluting.

The ideal plan is for fish farms to mimic oceans by mixing multiple, complementary species, including “cleaner fish” to control pests. Some Norwegian farms are already doing this, and they’re producing more biomass and less waste.

Ultimately, the industry must establish proper communication with regards to where the seafood was farmed, and certification of whether it was farmed sustainably. Until then, more often than not, be prepared for a seafood surprise.

Sources Used:

(1) all images: Wikkicommons












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1 Comment

  • Reply
    holly brighton
    Oct 21, 2014 at 6:45 pm

    So informative but upsett(l)ing! Thanks for the list of lower chain fish. Noted.

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