Can GM technology promote sustainable salmon farming?

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As wild populations of forage fish dwindle, new genetically modified false flax intended for salmon feed could relieve that pressure, while also boosting omega-3 in farmed salmon, according to an ongoing British research project. Populations of forage fish, which make up the natural diet of wild salmon, are threatened as the growing salmon farming industry requires more and more. Alternative feeds have so far lacked enough omega-3.

But public acceptance of the discovery has a few hurdles—opposition to genetic modification as well as the sustainability movement’s wariness of fish farming in general. AquaBounty, the company responsible for genetically engineering an Atlantic salmon, has faced significant opposition, with many advocacy groups wary of its sustainability claims. Although the salmon was cleared by the FDA almost two years ago after a expose by the Genetic Literacy Project’s Jon Entine in Slate, it remains locked in regulation limbo, reportedly because of ongoing political interference from the White House.

The AquAdvantage salmon genetically engineered by AquaBounty contains a growth hormone gene from a Chinook salmon to enable it to grow to full size in half the time. Many scientists believe that as world fish stocks are overexploited and demand for fish continues to grow, the GM salmon could help relieve pressure on wild fisheries through fish farming. It also brings fish to market faster meaning less wild forage fish for feed are needed to grow the salmon.

Additionally, AquaBounty’s land-based aquaculture model enables salmon to be farmed closer to the consumer, making it fresher and reducing the high carbon footprint normally associated with shipping long distance. “Compared to other farmed salmon imported from Chile, Norway, Scotland or Canada, our salmon would only have a short distance to travel from the farm to the plate, making it more environmentally friendly and sustainable,” said AquaBounty spokesman Dave Conley.


Yet there is a vocal environmentalist lobby opposing the AquaBounty salmon. Political watchdog and anti-GMO lobby group Food and Water Watch claims the salmon contains higher levels of a hormone that could cause cancer and has higher allergic potency. Additionally, it details its concerns about animal health and the environment:

frankenfishWhen GE salmon escape from commercial facilities, their impact on wild salmon populations and biodiversity could be significant. Because fish move freely through bodies of water, escapees are essentially impossible to capture.

Once GE salmon escape, they could outcompete wild salmon for food and even mates, quickly driving down wild populations.

The U.S. government environmental assessment dismisses such claims as exaggerated or outright wrong. AquaBounty has completed all the scientific studies need in the regulatory process and received preliminary approval from the Federal Drug Administration in 2012 yet the technology still hangs in regulatory limbo despite a 25-year history of research.

But ultimately, consumers just can’t seem to stomach genetically altered animals. In 2010, 78 percent of readers polled by the Washington Post said that they wouldn’t eat a GM salmon due to health and environmental concerns.2641228_431

Some environmental groups have done all they can to make sure it stays that way. Dana Perls, a food and technology campaigner at the international environmental network Friends of the Earth, which has worked to get retailers to reject the salmon, said, “The goal is to make sure there is not an available market for genetically engineered seafood. People don’t want it, and markets are going to follow what people want.”


While the tale of the AquaBounty salmon is symbolic of the public’s hesitancy over what would be the first genetically engineered animal for human consumption, two newer projects, including the British project, contribute what may be considered a more palatable GM solution to address salmon-related sustainability concerns.

Both innovations use algae, which produce omega-3, in genetic modification to provide a needed nutrient in fish feed. Researchers at England’s Rothamsted Research spliced genes from algae into false flax, whose scientific name is Camelina sativa. Meanwhile, the Verlasso salmon, which is already offered commercially, is a joint venture between the agribusiness DuPont and the seafood business AquaChile. Dupont uses genetic modification to combine algae and yeast for fish feed; then AquaChile grows the salmon.

The fish feed is essentially no different than feeding cattle GM corn or soy—a practice that is common even in Europe, where opposition to GMO food is high. Additionally, last year a review study showed that there is no detectable difference in animals fed GM feed versus non-GM feed in terms of nutritional makeup.

The added nutritional benefit for both fish feeds also makes them different from other GMOs—most GMOs on the market are engineered for herbicide-resistance or pest-resistance.


“I think consumers find it easier to swallow when they know you are engineering a plant for health benefits rather than to repel insects,” said Jonathan Napier, a principal investigator at Rothamsted.

Under pressure from environmentalists, many fish farms have reduced the amount of fish oil that contains omega-3s feed to salmon, relying on alternative vegetarian feeds instead. Napier explained that the GM flax feed would meet nutritional needs while also addressing an environmental concern:

Fish get fish oil from their diet when they swim in the sea but when you put them in a cage they can’t do that and you have to feed them smaller fish, otherwise fish would have no more Omega-3 in them than chicken.

Fish oil is actually obtained by fish eating or absorbing Omega-3 from microscopic marine algae, but to feed salmon forage fish are caught in the wild.

The problem is that there aren’t plenty of fish in the sea. One million tons of fish oil is removed from the seas every year and most of that goes into fish farming through fishmeal. It’s unsustainable.

As global demand of farmed fish has tripled between 1995 and 2007, scientists have become concerned about low stocks of forage fish that provide fish oil, like herring, smelt, sardines and squid. This is one factor that has earned fish farming some sharp critiques.

Related article:  Deposed EU scientific advisor Anne Glover says Greenpeace lied to oust her

“In the big picture, there are growing concerns globally that some forage fish stocks are unhealthy and the way we harvest them is unsustainable,” said Bill Sydeman, a marine biologist with California’s Farallon Institute.


It takes up to five pounds of forage fish to produce fishmeal for one pound of salmon, according to a 2009 study published in the Proceedings of the National Academy of Sciences. In 2006, while 51.7 million metric tons of fish were produced through aquaculture, it took about 20 million metric tons of wild fish to produce the fishmeal to feed them.

The study’s authors led by Rosamond Naylor, an economist at the Stanford Woods Institute of the Environment, suggested lowering the amount of fish oil in salmon’s diet by about four percent to reduce the need for forage fish to 3.9 pounds per one pound of salmon. To supplement, they suggested using plant-based solutions, such as fish feed from soybeans.

Chinook_salmon,_Oncorhynchus_tshawytschaIn some fish farms, salmon are fed an entirely seafood-free diet. In fact, the amount of fish oil and fish feed is a criteria used by environmental groups to determine sustainability, with preference given to less feed sourced from forage fish.

One problem this has spawned, however, is a nutritional change in salmon. According to the trade group, International Fishmeal and Fish Oil Organization, today’s farmed salmon could only have half the amount of omega-3s than the salmon of a decade ago.


That’s where the GM fish feed comes in. The fish feed made from flax can be tailored to human nutritional requirements, said Douglas Tocher, a research with the Rothamsted study.

The question is: Will sustainability advocates accept a biotech solution for fish feed?

It seems the jury is split. While Dupont says that it consulted with leading environmental groups, including the World Wildlife Fund, to focus on innovations that would reduce the need for wild feeder fish, Whole Foods won’t carry Verlasso’s GM salmon.

“Our customers prefer non-GMO when possible, so when we can source something without GMOs, we will certainly do that,” explained Beth Krauss, a Whole Foods spokeswoman. “If we can get farm-raised salmon without GMO feed being used, we will.”


Of course Whole Foods also has aquaculture standards, which Verlasso doesn’t meet. The company grows Atlantic salmon in the Pacific Ocean, while Whole Foods prefers fish from native waters. Also, Verlasso occasionally uses antibiotics, which are prohibited in the standards.

56061_105957In its yearly Seafood Sustainability Scorecard, Greenpeace, which shudders at any GMO technology, ranked Whole Foods the number one retailer for seafood.

But technologies like Verlasso’s have some potential to change attitudes about farmed salmon, which haven’t always been favorable. Verlasso maintains that its technology earned it a “good alternative” from the Monterey Bay Aquarium’s Seafood Watch program. The rating isn’t the highest, but it’s a first for ocean-raised farmed salmon. It’s only been four years since the Seafood Watch list included any farmed salmon in its top tier.

“If you go back 10 to 12 years, the red listing for farmed salmon was a shot across the bow to the farmed salmon industry,” says George Leonard, chief scientist at Ocean Conservancy. “And my sense is that message has been received. It shook the industry and brought them to the table.”


As the industry is changing, it’s also winning over some chefs, who now tout the benefits of farmed salmon.

Celebrity chef Rick Moonen not only switched to farmed salmon at his Las Vegas restaurant but he has become an ambassador for True North Salmon Company, owned by the large corporation Cooke Aquaculture.

“The fact is, we’ve over-farmed our land. We’ve over-fished the most popular species. We’re going to need large-scale, high-quality, environmentally responsible solutions,” he says. “Aquaculture has only really exploded over the last 30 years. The farmed salmon industry needs to come together like free-range chicken or grass-fed–beef folks.”

Of course, that’s not endorsement for Verlasso’s GM-fed salmon or Rothamsted’s research on GM fish feed, but it’s a step toward a changing conversation over farmed fish.


Genetically modified fish feed pushes that conversation on aquaculture’s role in seafood sustainability a little bit farther.

Rebecca Randall is a journalist focusing on international relations and global food issues. Follow her @beccawrites.

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