Free-living Atlantic and Pacific salmon have been a valuable food source for millennia. Hunter-gatherer groups resident along the coastal waters and major tributaries of North America caught what they needed while preserving the waterways that produced their harvest. Evidence exists of indigenous people having iconic relationships with salmon some twelve thousand years ago, from the Tlingits in Alaska to the Wyampum along the mighty Columbia River in the Pacific Northwest. Across the Atlantic, one of the oldest habitation sites in Ireland was discovered in 1972 at Mount Sandel, a bluff overlooking the River Bann. Careful analysis of evidence dating to before 7000 B.C.E. has shown that hunter-gatherers there erected huts, gathered nuts, hunted boar, and speared salmon.
Fast-forwarding through the centuries, legislation to protect salmon was enacted by William the Lion, who ruled Scotland from 1165 to 1214. In the thirteenth century, Norwegian legislation known as the Gulating Law and the National Law of Magnus Lagabøter regulated fair fishing conduct. During the Industrial Revolution, pressures on European waterways, habitat destruction, and pollution severely compromised the survival of salmon. Up until about 1800, the Thames, the longest watercourse in England, was an excellent salmon river. Pollution decimated the salmon—the last salmon was caught in 1833—and by 1855, the river was so contaminated that no fish could survive. A similar tale is true of the Rhine River in Germany. Up until the end of the nineteenth century, the Rhine was considered the best salmon river in Europe. In the early 1900s, the salmon disappeared because of hydroelectric development, and industrial pollution. The same pressures for manufacturing, development, and exploitation of energy resources were taking place in North America. Dams were being built, rivers were being polluted, and salmon populations were declining and, in some cases, becoming extinct.
As commercial fishermen became better skilled and better equipped, even more pressure was put on salmon stocks. In the absence of international regulation, the amount of salmon caught led to overfishing, without concern for the sustainability of either the fish or future fishermen. Not enough salmon were making it back to their natal rivers to spawn, in order to continue their natural life cycle. The demand for salmon exceeded the supply, which led to the beginnings of salmon farming.
Alaska, home to abundant stocks of salmon, is the only state in the nation whose constitution explicitly mandates that all fish, including salmon, “shall be utilized, developed, and maintained on the sustained yield principle.” As a result, Alaska’s wild salmon fishery ranks as the healthiest and best managed in the world. There are no salmon farms in Alaska. All Alaska salmon are wild, living in their natural habitat, growing to adulthood at their own pace, and eating marine life, which in turn colors each variety of salmon to its own hue. During the salmon season, biologists use sonar to assess the returning salmon at key streams and rivers. Regulating and managing the salmon runs ensure that spawning salmon return in sufficient numbers to produce future generations. Alaska also strictly regulates fishing. A limited number of licensed fishermen using regulated gear are allowed to fish in state waters up to three nautical miles offshore for restricted periods of time.
The salmon populations in Washington, Oregon, and California experienced some of the same pressures that befell European salmon stocks. Demand for hydroelectric power led to dams being built on key salmon rivers such as the Columbia, which divides Oregon and Washington. The development of urban and agricultural watersheds resulted in the polluting of rivers and streams. The consequence of these compounding factors has caused salmon populations to decline, and in some instances, become extinct in all three states.
So far, salmon aquaculture has been limited to a few sites in Washington. Oregon’s coast isn’t well suited to salmon farming (thank goodness!), as ocean net pens need both a constant rush of water to flush waste and the relative protection of a large bay. And, to the best of my research, California does not have open-net-pen salmon farms on its coastline. However, all three states and Alaska have extensive fish hatcheries that raise young salmon (eggs, fry, and juveniles) that are released in the wild. At this point, 70 to 80 percent of wild-caught salmon and steelhead in the Pacific Northwest originated in fish hatcheries. Biologists focused on wild salmon stocks see the benefits that salmon hatcheries can provide, but they also know that reliance on hatcheries as a substitute for the conservation of wild populations is a risky long-term conservation strategy.
Finally, the newest pressures on salmon habitat in southern Oregon and northern California have come from the growth of the marijuana industry. In January 2014, biologists at the National Oceanic and Atmospheric Administration (NOAA) released a report citing the unregulated use of fertilizers and stream-sucking irrigation systems by marijuana growers and the risk they pose to Oregon and California rivers, where chinook and other salmon swim.
In the 1950s, commercial fishermen began using sonar and drift nets to catch a record number of salmon gathering in the sea around Greenland and the Faroe Islands. The salmon were migrating from rivers in the United States, Canada, and Europe. Without regulation, the life cycle of the Atlantic salmon returning to their natal waters to spawn was interrupted, and it didn’t take many years before the annual numbers crashed, resulting in the collapse of wild Atlantic salmon stocks.
Early recognition of this overfishing led pioneers to start researching and developing salmon farms in the 1960s. By the early 1970s, the industry was well under way in Norway in an effort to meet the growing demand for salmon in the marketplace. Scotland soon followed. Both of these areas were attractive as locations for fish pens because of the stretch of coastline, much of it protected from storms. Sheltered coastal waters warmed by the Gulf Stream, with nearby rivers providing the freshwater needed to operate fish hatcheries, have also been ideal for growing salmon. By 1985, technology had evolved so that farmers could raise almost 200 tons of salmon in pens that produced only one-third of that amount the year before. As profits soared, a gold rush of sorts ensued.
By 1986, approximately 635 salmon farms produced 45,675 tons of salmon; by 1990, production had grown to 146,000 tons.
With a glut of salmon on the market, prices fell. Salmon farmers from Scotland and Ireland accused the Norwegians of dumping salmon on the market below production costs, which led to an investigation by the European Union. As government restrictions were put into place, large aquaculture companies began exporting technology, equipment, and financing to other countries, the largest of which were Canada, the United States, and Chile.
Today, with both steady growth and rising demand in the market, aquaculture overall accounts for almost half of all the salmon destined for human consumption. In 2013, the total supply of all farmed salmon was almost two million tons. In the same year, the total catch of wild salmon (with pink, chum, and sockeye the most common species) was just under one million tons. What is new in the industry since I wrote my first salmon cookbook in 2005 is how the fish is processed. That work is now done with cheaper labor costs. Instead of processing all the fish locally, about 25 percent of the total catch of wild salmon from the United States, Russia, and Japan is exported as whole frozen fish to China, where it is processed much less expensively than is possible in the country of origin. It is then re-exported as frozen fillets.
The challenges of wild versus farmed salmon are both environmental and economic. Salmon farming, like most intensive forms of producing food, has significant environmental costs. Escapement is a huge issue. Large numbers of salmon escape from sea pens both routinely and in severe weather. Interbreeding of escaped salmon undermines the genetic robustness of wild salmon and also infects wild salmon with parasites and diseases. In British Columbia, escaped Atlantic salmon, a farmed species not native to Pacific waters, have populated a number of rivers. Diseases and infestations can spread rapidly to fish raised in overcrowded sea pens. Fish farmers combat these outbreaks using antibiotics, often resulting in disease-resistant bacteria turning up in the intestines of farmed fish. Sea lice, which were rarely found on the scales of wild juvenile salmon in the past, are now regularly seen on them. Uneaten feed and feces from salmon accumulate beneath the sea pens, contaminating the water, depleting oxygen levels, and releasing noxious gases in decomposition.
New technology is changing some of these aquaculture practices for the better. Although currently used in only a few sites, a closed containment system with an impermeable barrier that physically separates the fish from the external environment is a promising direction. It prevents the transmission of diseases and parasites, eliminates escapement issues, requires fewer chemicals, and uses less feed, which lowers the pressure on wild fish used in feed. It also treats waste within the system, rather than discharging it into the ocean, thus virtually halting pollution of the marine environment. Unfortunately, the investment dollars and cost per fish are keeping this system limited for now.
Another challenge of aquaculture, focused on salmon specifically, is the amount of little fish it takes to produce the feed to grow the big fish in a fish-farming operation. Historically, fish feed has been made from fish meal and fish oil from forage fish such as anchovies and sardines. Annually, these fish represent nearly one-third of the global fisheries’ catch, and they are mostly processed into fish meal and fish oil used in fish, poultry, and livestock feeds.
The ongoing concern of biologists and environmentalists is that this catch rate is not sustainable. The fish feed industry has replaced these marine raw materials with agricultural commodities that mimic the omega-3s found in the small fish. Products such as soy, sunflower, wheat, corn, beans, peas, rapeseed oil, and poultry by-products (in Chilean and Canadian aquaculture) are combined and used in place of marine-based feed. Fish meal and other raw materials of animal origin have a more complete amino acid profile than protein of vegetable origin and generally have a higher protein concentration. That means that completely replacing fish meal poses a big challenge. The optimization strategy for this industry is to grow a healthy fish fast at the lowest possible production cost. Some aquaculturists are focused on premium feed for their salmon and are branding their salmon products accordingly.
As consumers, we are the responsible ones. We can vote with our pocketbooks. It is our job to understand the true cost of a $7.99-per-1-lb [455-g] salmon fillet in a broad context. Buying wild salmon, or buying responsibly farmed salmon from a farm with a recognized certification of quality, costs more, but it is the only way to avoid contributing to the overwhelming environmental and economic impact caused by these agrochemical fish farms. We need to ask questions and, hopefully, to buy only fish that meet a high standard of excellence, whether at the grocery store or in a restaurant. I recognize I am privileged living in the Pacific Northwest because I have easy access to wild salmon, so my position is, “I eat wild to save wild.” It’s my way of voting.
