Fish to Feed the World

by Sarah Janes Ugoretz

In our July 4th newsletter, we kicked off a series featuring National Geographic’s eight-month exploration of the future of food. Here, we take a look at the second feature article in the series, “How to Farm a Better Fish,” in which author Joel K. Bourne examines modern day fish farming, which has become a rather contentious issue over the last several years.

Aquaculture is essentially the cultivation of aquatic life for food. As a practice, it has been traced back at least 2500 years to Chinese farmers who introduced carp to their rice fields. Unlike the symbiotic approach adopted by the Chinese so long ago, however, modern day agriculture has evolved into something quite different. Although complexities remain, Bourne quickly and plainly states the basic issue at hand:  “The problem isn’t the ancient art of aquaculture per se; it’s the rapid intensification of it.” Intensification of a production model typically signals a rising demand for the final product, and this is certainly true of the seafood business. Over the last few decades, increased consumption of seafood has resulted in double-digit growth rates within the industry. Today, nearly half of all seafood comes from aquaculture.

Supporters of aquaculture point to something called the “feed conversion ratio.” Basically, the amount of food that it takes for a fish to gain one pound of body mass is lower—at times, significantly so—than that required by other common sources of animal proteins, like beef, poultry and pork. According to Bourne, “As a source of animal protein that can meet the needs of nine billion people with the least demand on Earth’s resources, aquaculture…looks like a good bet.” Based on this optimism, fast-growing varieties of carp and tilapia have been developed to aid in the advancement of the Blue Revolution, as this approach has come to be called.

However, just as with the Green Revolution—which Andrea and Richard discussed several weeks ago—the Blue Revolution has had a myriad of criticisms levied against it. Habitat destruction, water pollution, and food safety scares have gone hand-in-hand with the rise of intensified aquaculture. Perhaps more immediately urgent for the U.S., which imports 90% of its seafood, is the widespread use of antibiotics and pesticides by countries dominating the industry. Many of these substances have been banned for use in the U.S. and include suspected or known carcinogens. With only 2% of seafood imports being inspected by the U.S. Food and Drug Administration (FDA), oversight is sorely minimal.

Approaching this topic from a critical stance should not, however, automatically render aquaculture participants as “the bad guys.” Take the words of a Chinese fish geneticist, quoted by Bourne: “That is my duty. To make better fish, more fish, so farmers can get rich and people can have more food.” There is no doubt that profit motives abound and drive the intensification of industries like aquaculture and agriculture. And yet, there remains a real and pressing need to find ways for farmers to survive economically, and for the world’s people to access safe and nutritious foods regularly. These are answers that we are still looking for.

Fortunately, positive examples of successful, environmentally friendly aquaculture models exist and may offer a platform off which the industry as a whole can begin moving forward. Bourne shares with us one such operation. Run by Brian O’Hanlon, an American working off the coast of Panama, Open Blue is the largest offshore fish farm in the world. Anchoring his pens of cobia 60 feet below the surface, O’Hanlon has been able to use dilution—basically the rushing of water through his pens—to avoid both pollution and disease. Thus far Open Blue has avoided using antibiotics to keep their fish healthy, and researchers from the University of Miami have not been able to detect any traces of fish waste outside the pens. This type of system, O’Hanlon insists, “is the future.”

One major issue that remains unresolved with Open Blue’s operation, however, is the food requirements of the fish O’Hanlon is growing. Cobia are carnivores, and voracious ones at that, and therefore feeding them places significant pressure on the bottom of the food chain. Aquaculture critics insist that building a system in this way is not only superficial, but it is akin to “ecological insanity.” As Bourne points out, “Figuring out what to feed farmed fish may ultimately be more important for the planet than the question of where to farm them.” Fortunately, more fish farmers have begun working with omnivorous fish, like tilapia.

While reading this article, my mind kept returning to Milwaukee’s Will Allen of Growing Power, Inc and his work with aquaponics. While this system differs from aquaculture in that it incorporates fish into a re-circulating system that includes edible plants, there is certainly a place for aquaponics in this discussion. One of the more notable aspects of Allen’s operation is its water filtration system, which is set up to convert the toxic ammonia found in fish waste into Nitrogen, which in turn fuels healthy plant development. O’Hanlon insists that re-circulating systems like Growing Power’s won’t be able to produce enough fish to feed the world. This is likely true, but just as small-scale vegetable farmers fill a niche by catering to their regional population, small-scale aquaponics systems can meet localized demand, support local and regional economies, and serve as an alternative to large-scale production. Meanwhile, if businesses like Open Blue continue to refine their practices and work towards a more environmentally friendly means of providing healthy and affordable animal protein to a broader swath of the population, fish farming might just become the wave of the future.