The Trouble With High-Tech 'Sustainable' Aquaculture

Why genetically modified fish and other seafood innovations don't address the root of the world's fisheries crisis

AquAdvantage Salmon.jpg
An AquAdvantage genetically modified salmon. Courtesy of AquaBounty

When I give lectures about the state of our food system, the questions that surprise me most are those wrapped in strongly held beliefs about seafood. There seems to be an equal bias in favor of wild fish—"farmed fish are 'unhealthy' or 'unsafe'"—as toward farmed fish—"the oceans are over-fished so I eat only farmed fish." On both sides, myths are rampant.

Bryan Walsh of TIME waded into this swamp of misinformation last week with a cover story called "The Future of Fish." Walsh's work is typically thoughtful, and this piece is no exception. He outlines the statistics that worry marine scientists: 32 percent of global fish stocks are already over-exploited or depleted, 90 percent of large species such as tuna have been fished to "near oblivion," and the worldwide catch has plateaued in the last two decade. There's still a lot of fish in the sea, but even if the catch is managed sustainably—a big "if"—it wouldn't be enough to meet rising demand from the millions of newly middle-class citizens in the developing world who want it or the poor in coastal communities that depend on it.

The answer, Walsh contends, is more aquaculture. "Farming is unavoidable," he concludes.

No knowledgeable observer would disagree. Walsh artfully lays out many challenges that ramped-up aquaculture poses. He also points out that large-scale aquaculture, unlike crop farming and animal husbandry, is only a few decades old. For that reason, he cuts fish farmers some slack.

Perhaps too much slack. While acknowledging that most of the environmentally responsible aquaculture operations in existence today are smaller-scale operations, he (like many others) is mostly uncritical of genetically modifying seafood as a means to supplying more fish, even going so far as to label opponents "knee-jerk" in their resistance.

One approach to meeting demand, Walsh suggests, "is to take the fish we like and engineer them into sustainability." Really? Seems like a safer bet would be to take inherently sustainable fish species, such as perch and trout, and get more people to like them. Or to develop more mid-scale operations that, by their very size, minimize the risks of escapes and disease transfer.

The few large-scale operators that are positively rated by conservation organizations grow fish in land tanks that come with high energy inputs, an environmental cost generally not measured by marine scientists. Others are lauded for using grains rather than fish meal to feed their farmed creatures. That's good for the ocean's stock of healthy little fish, but not good when the fertilizers applied to grow the grains create dead zones in the ocean like the massive one in the Gulf of Mexico. Scaling up in concentrated locations has its problems.

Given that we've had real issues scaling up responsibly, why would we want to add another level of complexity and introduce genetically modified organisms (GMOs) into large-scale aquaculture? Where Walsh and many others stumble is in their general—if not wholly uncritical—acceptance of genetically modified fish as a way to feed a growing population. Thoughtful experts disagree about whether GMOs may have a role in the future of food, but it's foolhardy to hang the future of the world's seafood supply on an idea that has proven problematic with crops where they've had decades of testing.

Paul Greenberg recently offered a blunter observation of GMO fish farming in the context of the U.S. Environmental Protection Agency's pending decision to allow a gold mine in Bristol Bay, Alaska. Open pit mines near rivers have been notoriously bad for fish, the author of the award-winning Four Fish claims, citing the copper mine failure in China's Ting River that killed millions of fish. A similar disaster in Bristol Bay could destroy the same amount of salmon that the company responsible for genetically modified salmon hopes to produce.

"Instead of endorsing a risky experiment in genetic salmon modification, wouldn't it be better if our leaders protected wild salmon habitat?" Greenberg said on the public radio show Living on Earth. "In the end, we'd have just as much fish on our plates and a safer environment to boot."

Granting approval to sexy new technologies will always be easier than managing wild stocks. But easy isn't supposed to be the goal; long-term sustainability is. Besides seafood's importance as sustenance for a growing world population, it rivals chicken as the most environmentally efficient form of protein. In short, we need seafood, especially the diversity of species that make for healthy ocean ecosystems. GMO salmon probably isn't compatible with that vision. As we begin to fundamentally question whether large-scale agriculture can provide a genetically diverse abundance of healthy food for people and the land in which it is rooted, we owe it to ourselves to question the same arguments being used to promote large-scale aquaculture.