Paul Greenberg would have had one less chapter to write in Four Fish: The Future of the Last Wild Food had fellow author Mark Kurlansky’s 2000 best-seller Cod caused a swift change in the way cod are harvested today. Although Kurlansky provided crucial information about the deleterious effects of industrial fishing, we left the responsibility of change to others. Greenberg is now attempting to revive the “bad human behavior of former times” to consciousness. His Pollan-esque investigation into our food chain—by way of salmon, sea bass, cod, and tuna—is as much an exposé on the fishing industry as it is a comment on “Modern” man’s desire to rule a larger food chain than was intended for him.

Recent technological advances have allowed us to see enormous potential for fish domestication. But “just because we can tame a fish,” Greenberg says, “doesn’t mean we should.” The fundamental problem with our relationship to the sea is that we view it as abundant and “free of charge.”

It is not shocking that Greenberg’s 4 investigations into industrial fishing and fish farming speak to the same sustainable concerns that infect the meat industry (scale, ecology, humane treatment of animals, to name some). But by nature of the fact that we still eat wild fish, the concern with large-scale fishing and fish farming goes beyond the system itself. Wild fish are wild animals. That distinction is important to Greenberg, who views declining fish populations as something akin to man’s contest against his own gluttony. “We are now deliberating over whether fish are wildlife—wildlife that is sensitive to our actions and merit our sound protection and propagation.”

The exploitation mapped in Four Fish points to human faults: consumers don’t want to be denied the freedom to choose what to eat; government subsidies and industry regulation are misallocated or absent, and an understanding of and respect for wild life systems has not yet been inculcated. To grasp the complex natures of the fish, Greenberg presents their interesting biological stories and historical relevance.

Salmon have strong genetics and are adaptable to new environments, but they need clean, oxygenated rivers to survive in the wild. Sea bass have a unique swim bladder which allows them to achieve a state of weightlessness when the bladder inflates with gas to keep the fish buoyant in lower depth waters. Their flesh is less muscular (and therefore lighter and whiter) because of this evolutionary aid. Cod, like bass, have lighter muscle tissue. They store oil in their liver instead of their flesh, which means that they are ideal fish to preserve. Tuna are highly muscular fish and require large amounts of the chemical ATP to keep their energy levels high. ATP converts into IMP after a fish’s death—its raw flesh rich with a chemical that produces the “fifth” sense or umami flavor so prized by Japanese culture. These fishes’ appeal has contributed to their decline.

Over the last twenty years, human consumption of salmon—farmed or wild—has doubled. In places like Turner Falls, Massachusetts, where more than 100 million salmon larvae once hatched in the Connecticut River, wild salmon now cease to exist there—a development that occurred in 1798 after a large dam was built across the river, blocking fish from making their trip home to spawn. As the waters of Greenland became packed with Atlantic salmon with no place else to go, Danes, Norwegians and Swedes furiously fished the waters throughout the 1950’s and 60’s, bringing the wild Atlantic species to commercial extinction. The memory of abundance stoked a desire to reclaim control over a salmon population. Greenberg’s logic: “Farmed salmon reclaimed that lost memory.”

The sea bass is less adaptive to captivity than salmon. Still, there are ten times more sea bass grown than caught every year. In captivity, their spawning patterns are hard to induce, their juvenile bodies are fragile, and their nutrient requirements are demanding. But in 1982, after the US issued a three year moratorium on the sporting and commercial fishing of the American striped bass—a fish that had reached its lowest population level by the 1970’s—the bass maintained its reputation as a rare “holiday fish.” Israelis had conducted years of scientific study in 1960’s, experimenting with manufacturing a hormone to control spawning patterns in captivity. But it was the Greeks who seized on an occasion to domesticate the finicky fish in the midst of 1980’s moratoriums. Their investigation into the nutritional needs of juvenile bass grown in captivity built upon the Israeli hormone trials and French/Dutch juvenile feed studies. “The stage was set for the sea bass to go global,” says Greenberg. Go global it did: Greece sends about 100 million sea bass to Europe and the US every year.

Not surprisingly, the 1982 sea bass ban was a precursor to stricter prohibition. In 1994, the United States banned commercial cod fishing in George’s Bank. This move was the result of heavy over-fishing encouraged by government subsidies just two decades earlier, to help build the water’s fishing fleet. Present and former generations of cod eaters have come to know different waters—with severe fishing limits on a species once considered the “everyday” fish.

As Greenberg moves his investigation through rivers, to coastal waters and then to continental shelves, his exploration ends in deep, unregulated waters with the plight of the bluefin tuna. Never has bluefin tuna been as plentiful as salmon, sea bass or cod. Its value as seafood is a recent advancement—a 20^th century emergence in Japan that then caught on in the States only a few decades later. But when we compare a fish of such massive size with another giant of the sea, the whale. Whales are valued as wild animals, protected against human exploitation. Bluefins are valued as a delicacy, not yet considered untamable by fisherman and regulators. Greenberg views our behavior toward bluefin as arbitrary: “It is the battle with ourselves. A battle between the altruism toward other species that we know we can muster and the primitive greed that lies beneath our relationship with creatures of the sea.”

So what are our options? Greenberg envisions an ocean with small-scale, expert fleets, fish reserves that foster natural spawning and protect habitats, bans on fishing animals that are unmanageable and regulation of waters where forage fish need protection in order to flourish. To compensate for consumer demand, fish farms would still continue to be in existence but operate in keeping with “sustainable” measures: fish would be selected for their naturally low feed conversion rates and positive response to captivity, environments would be harmless to the natural ones that share the waters, feed would be sustainable and vegetarian, and most importantly, a polyculture technique would ensure that all organisms in the system contribute to and benefit from a self-sufficient life cycle.

To allow salmon, sea bass, cod, and tuna the lives they were intended—those in the wilderness—other fish of similar genetic make-up that respond well to captivity can offer possibilities for sustainable fish farming. It isn’t the inevitability of fish farming that Greenberg denies nor does he see the system coming to an end. “Contemporary demand is so large that any natural system is going to be taxed when subject to humanity’s global appetite.” His Bittman-like rationale: Just eat less fish in general.

By asking ourselves which fish are still “good” to eat (read: fish low in mercury and PCB levels, and still acceptable to eat by public standards), we may rethink our relationship with the sea. Greenberg’s Four Fish will only bring “bad human behavior of former times” to an end, if man recognizes the limits to his supremacy and relearns what early man knew better. That “he had no idea of his destructive potential or of his abilities to remake the world.”

The drive from San Francisco to Monterey cuts directly through the heart of commercial California agriculture. The road winds past thousands of acres of coastal crops, industrial-sized sprinklers, and crews of laborers stooping to hand-cut heads of lettuce and pick strawberries. It’s the kind of monocropping known for methyl bromide, nitrate contamination, and a whole range of other environmental problems.

These farms made for a useful comparison, however, when it came time to talk about fish farming at the Monterey Bay Aquarium’s recent Sustainable Food Institute.

The panel in question was called “Greening the Blue Revolution” and it brought together experts from a variety of disciplines to discuss the ecological challenges involved in fish farming. The panelists didn’t agree on everything but one thing was clear: many of the principles that apply to farming sustainably on land should also be applied to aquaculture.

As wild seafood becomes increasingly scarce, aquaculture continues to grow steadily. According to panelist Howard Johnson of the Sustainable Fisheries Partnership, around 50% of the seafood we consume globally (around 52 million metric tons) is farmed. And yet, like agriculture’s Green Revolution, the first several decades of fish farming have been geared purely toward production, with little thought toward its ecological impact.

Aquaculture has made once-luxury foods affordable; as much as 80% of the fresh and frozen salmon consumed in the US are farmed, for example. And while the price is right, said Roz Naylor, Professor of Environmental Earth System Science and Economics at Stanford University, “the cost may actually be very high in terms of the externalities.” For example, aquaculture sites are known to foster parasites like sea lice that can impact nearby wild salmon populations, farmed fish escape (to cross-breed with wild fish and compete for resources), and larger marine animals are often killed when they get too near these pens.

Peter Bridson, Aquaculture Research Manager at Seafood Watch, has observed first hand what he calls the “huge boom-bust cycles of disease, overproduction, poor economics and marine resource use” associated with commercial salmon and shrimp farming. But, he says he sees signs that things are changing. For instance, Seafood Watch recently named its first green farmed product – Pacific Coho salmon raised in fresh water closed containment systems. Only one such system exists to date, but Bridson is optimism that it could be scalable.

The Feed Race

The industry’s real “Achilles heel,” the panelists agreed, is what (and how much) farmed fish eat. While aquaculture is ideally meant to lighten the pressure on wild fisheries, that has yet to become a reality; in fact, for as long as farmed fish eat a diet based on fish meal and fish oil (made from wild seafood), the two will remain inextricably linked.

“As aquaculture grows, it will place more and more pressure on forage fisheries,” said Naylor. Forage fish are the smaller species – sardines, menhaden, pollock, herring, and krill – which are caught mainly as food for larger species. Just like in the case of livestock production, where a great deal of the land is used to produce grain to feed cows and pigs, many aquaculture researchers are concerned about just how much ocean biomass is being used to feed carnivorous fish like salmon, tuna, and shrimp.

Over the last decade, Naylor added: “there have been enormous gains in terms of the efficiencies of feed conversion, of lowering the inclusion of fish meal and fish oil in the feed.” And there has also been a concerted effort to move toward farming vegetarian species such as carp and tilapia. However, Naylor points out, those species are also now being fed fish meal to speed up growth. Almost 50% of carp and over 80% of tilapia eat feed made up of around 5% fish meal. This may seem small, said Naylor, but “if you add up the volume of all this fish and look at how it contributes in sheer tonnage, it’s big. Carp is now using almost as much fish meal as salmon is. So it’s really a race between improvements that we can make per fish and the volume of increase that we’re seeing [in production].”

If not wild fish meal, what exactly should we be feeding farmed fish? This is where things get tricky. Naylor detailed a whole range of recent efforts – from soy and other plant-based foods, to genetically modified canola and linseed, to single cell proteins and yeasts and animal byproducts such as feather meal from poultry.

And while these solutions would indeed take pressure off the oceans (poultry byproducts, for instance, are already in use), they raise other familiar concerns. During the Q and A session, Grist food editor Tom Philpott got right to the heart of the livestock-aquaculture comparison. “Shifting cows from grass to corn turned out to be very bad for cows,” he said. “I’d be very surprised if shifting salmon to corn could be good for salmon. And the last thing we need in this country is another market for industrially produced corn and soy.”

Seafood Watch’s Bridson responded, in regards to the recently green-lit farmed Pacific Coho. “In that case it was mainly because it was a closed system,” he said. “We don’t assess those bigger picture things, such as how reducing fish oil might lead to using genetically engineered soy, which could have an impact on Amazon rainforests. Those are all of real concern, but – at the moment – we’re focused on the oceans.” In other words, more immediate environmental issues have often overshadowed the question of feed in aquaculture.

In pure efficiency terms, the “green” Pacific Coho feeding system is far better than most; its feed ratio has been reduced to 1.1 pound of wild fish to 1 pound of farmed fish – an impressive number compared to most farmed salmon which requires as much as an 8:1 ratio. None the less, Bridson admitted that there are much larger questions at hand, and he said he hopes to have a more complete range of life cycle data available to incorporate into the Seafood watch analysis in the future.

Roz Naylor is also interested in larger questions about the full life cycle of fish feed. “This is really important question for all of us,” she said. “On the terrestrial side, if you’re not using [industrially farmed grain] for salmon feed, you’re using it for poultry, cows, or biofuels.” On the consumer end, she added, there may also be ways to stem the tide of demand for carnivorous fish. “Maybe we should be eating much less food that requires any feed, because all of these systems are crucially linked.”

There’s More than Fish in the Sea

As with agriculture, part of the answer to our aquaculture bind may lie in diversification.

Dr. Thierry Chopin, a marine biologist at the University of New Brunswick, spoke about his work to counter the trend of monoculture in fish farming with systems that integrate several aquatic species farmed in proximity. The method he uses is called Integrated Multi-Trophic Aquaculture or IMTA and it involves farming fish, shellfish and seaweed together. Fish create nutrients that can be polluting in excess, but when kept in small numbers, in proximity with other species, such as mussels, sea urchins, and seaweeds (which absorb the nutrients in various stages) the end result is what Chopin’s website calls “an age-old, common-sense, recycling and farming practice.”

Chopin pointed out that 44% of the biomass produced at sea is seaweed, while 44% is shellfish, and only around 9% is fish. His hope is that the food perceived “lower value” will gain enough traction in the developed world so as to balance the production needs and make IMTA a viable model for aquaculture producers (several fish farmers in Canada have already adopted the system). “Sea plants will have a lot of protein, especially when grown next to salmon, a source of nutrients,” he says.

Peter Bridson agrees. “There is so much more to the blue revolution than salmon and shrimp,” he says. “We have this kind of ongoing obsession with these species, but there are huge production volumes of shellfish and freshwater fish and seaweeds…and these really do have the potential to be so much more sustainable.”

Photos: School of Coho by Greg Dunham, Salmon farm by Byron Wee

It seems like not a week goes by without industrial animal food production somehow making headlines–the H1N1 flu pandemic, astounding meat recalls, high levels of arsenic in chicken feed, or any of a dozen other concerns. One recent story that should have generated some rather large waves, however, has made only a minor splash. Chile’s salmon farming industry, second only to Norway’s, is on the verge of collapse.

Salmon are not indigenous to Chile, but grown in crowded cages installed in the bays and estuaries of the country’s otherwise beautiful southern fjord region. These “farmed” Atlantic salmon are fed a steady diet of wild fish–perfectly edible for humans, but more profitable when converted into “value-added” finfish. The approximately three pounds of wild fish needed to produce each pound of farmed salmon has caused some people to refer to finfish aquaculture operations as “reverse protein factories.” Equally alarming, salmon farms have become excessively dependent upon toxic pesticides to combat sea lice and antibiotic medicines to thwart viruses that can run rampant among the high concentrations of rapidly growing, penned fish–not unlike industrial-scale hog, poultry, and cattle CAFOs on land.

But the drugs are no longer working. According to industry source Intrafish, Chile’s 2009 salmon output could decline by as much as 87 percent from last year–a drop from 279,000 metric tons in 2008 to between 37,000 metric tons and 67,000 metric tons. The cause is the widespread outbreak of a virus known as infectious salmon anemia (ISA). When the virus first appeared in 2008, many offshore aquaculture companies moved their production farms further south in Chile, into waters still unaffected by ISA. Instead of lessening the problem, the industry actually spread the virus into the southern waters.

The Chilean government and regulatory agency are now implementing measures to address the crisis, but their efforts, for the time being, have been too little, too late. Chilean salmon stocks have been devastated, and this is expected to send ripple effects throughout the world’s food supply. A 20 percent shortfall in the global supply of farmed Atlantic salmon is predicted for this year and perhaps 2010 as well. The human toll in this saga is also significant, as the salmon industry has become a primary employer in the southern region of the country, and could lead to the unemployment of as many as 15,000 people.

Experts had been cautioning for years about the hazards of unsanitary conditions and overcrowding in industrial salmon cages. The first widespread die-offs due to ISA began to mount early in 2008, but the industry declined to take protective measures to guard against further spread of the infection. Critics have called for improved conditions by limiting the number of salmon in the cages and by spreading the farms farther apart from one another to avoid transfer of disease and to lessen the concentration of harmful chemicals, antibiotics, and other adverse affects of large-scale fish production.

Unfortunately, this has not been the only alarming news in 2009 about Chilean aquaculture. In February, the Pew Environment Group obtained documents [PDF] from the US Food and Drug Administration (FDA) revealing that the Chilean salmon industry has been using antibiotics prohibited on fish destined for the United States. (Pew wrote a letter [PDF] to the FDA) Apparently, the FDA notified the three companies guilty of using the unapproved drugs that they can no longer use them on fish raised for the U.S. market. But questions remain whether or not the FDA will enforce these restrictions, and if so, how they will go about ensuring that the banned substances are not used.

Concerns over antibiotic overdosing and its potential to create antibiotic resistant disease organisms that could harm humans may become less of an issue if the Chilean salmon industry suffers an even further decline. Many are calling for a dismantlement of the industry. Others caution that without real reforms it could implode of its own unsustainable production practices. At a minimum, we should take this as one more in a long series of wake-up calls that our concentrated animal food operations–whether on land or at sea–need to be urgently reconsidered, before they are all on the verge of collapse.

Photo: Sam Beebe / Ecotrust