Aquaculture’s Troubled Harvest

Raising salmon in ocean pens was supposed to preserve the wild and feed the world. But all over the globe, industrial-style fish farming is threatening native fish and the ecosystems that depend on them. The latest battleground: British Columbia.

Fight disinformation: Sign up for the free Mother Jones Daily newsletter and follow the news that matters.

Most folks welcomed the salmon farms when they came to the Broughton Archipelago 14 years ago. The people who live in these remote Canadian islands 250 miles north of Vancouver thought they were getting an eco-friendly industry that would ease the pressure on the region’s dwindling wild salmon runs. “I figured they’d offer people jobs, attract new families, and keep our community alive,” recalls whale researcher Alexandra Morton.

It’s easy to see what had attracted the farmers. The archipelago, a puzzle of islands scattered through hundreds of miles of fjords, remains one of the richest pockets of biodiversity on the North American coast. Forests choked with second-growth cedar, hemlock, and Douglas fir grow straight down to the high-tide line. Cold, green salt water—storm-sheltered and teeming with nutrients stirred by the tidal flush—nurtures five species of wild salmon, which in turn support a dazzling cast of creatures: dolphins, porpoises, seals, sea lions, great blue herons, and one of the world’s largest populations of killer whales. Bald eagles are as common as gulls. Barnacles grow as big as a lumberjack’s thumb.

At first, the farmers trod lightly, consulting with local fishermen to find sites that wouldn’t harm wild salmon runs. But a few years after the farms arrived, things began going wrong. Big corporations bought out smaller operators; the farms metastasized and anchored their net pens in places where wild salmon smolts rested and fed on their way out to sea. Shrimp fishermen began pulling up traps full of farm muck, a gooey black mixture of feces, excess antibiotic-laden fish feed, and decayed salmon carcasses that filtered out of the pens. Piercing acoustic sirens installed to keep seals and sea lions away from the salmon pens drove the killer whales out of the archipelago. To rid their fish of sea lice, farmers dosed them with ivermectin, a potent antiparasitic known to kill some species of shrimp. Farmed fish contracted antibiotic-resistant strains of furunculosis, a fatal disease that produces ugly skin ulcers; wild salmon that migrated past their pens also contracted the disease.

“I’ve been catching salmon up here all my life,” says Chris Bennett, a fishing guide who runs a floating lodge in the archipelago. “I’d never seen a fish with a lesion until the farms came in.”

Some of the early farmers raised native Pacific chinook and coho, but most soon switched to the more profitable Atlantic salmon. The fast-growing, hardier, and comparatively docile Atlantics adapted better to life in a crowded pen. When local environmentalists voiced alarm about introducing the nonnative Atlantic species into Pacific waters, the industry and the provincial government dismissed their worries. If any escaped, they said, they’d never survive. “These fish are inept at surviving in the wild,” says Anita Peterson, spokeswoman for the British Columbia Salmon Farmers Association. “They’re seal and sea lion fodder.”

The fish did escape, either because of human error or when storms or hungry sea lions tore the nets. According to the Canadian government, in the past decade nearly 400,000 farm-raised Atlantics escaped into British Columbia waters and began competing with wild species for food and habitat. (That number relies primarily on escapes reported by fish farmers; environmentalists put the actual figure closer to 1 million.) And they survived. After years of speculation about whether Atlantics could make it on the lam, in 1998 researchers found that Atlantics had actually spawned in the Tsitika River on Vancouver Island, a few miles west of the archipelago. By the summer of 2001, Atlantics had turned up in 77 British Columbia rivers and streams.

“We were told they wouldn’t escape. They escaped,” says Jennifer Lash, director of Living Oceans Society, a local conservation group. “We were told they wouldn’t survive in the wild. They survived. We were told they wouldn’t get upstream. They got upstream. We were told they wouldn’t reproduce. They’ve reproduced.”

Instead of relieving the pressure on wild salmon, industrial fish farming has become one of their greatest threats. Besides mucking up the farm sites and passing lice and disease on to wild fish, escaped Atlantics threaten to outcompete an already stressed population of Pacific salmon, replacing a diverse genetic pool with a single strain of invasive fish that may be ill adapted for long-term survival.

An environmental outcry forced the provincial government to impose a moratorium on new farm sites in 1995 and to subsidize farmers if they experimented with greener, solid-wall pens. But the industry responded by stuffing twice as many fish into the 87 active sites. By 1999, British Columbia’s fish farmers were cultivating $292 million worth of farmed fish, more than 11 times the value of Canada’s wild Pacific salmon catch.

Now, with British Columbia’s industry-friendly premier, Gordon Campbell, in office and the province hurting for jobs, the industry is pushing to open new megafarms in some of the region’s most ecologically sensitive spots.

“I can appreciate the value of the jobs,” says Glen Neidrauer, a game warden who patrols the archipelago for Canada’s Department of Fisheries and Oceans. “But why would you jeopardize a place so pristine? We’re not just talking fish—all the birds, bears, and sea mammals depend on wild salmon. I wonder how long you can mess with that until they finally don’t return.”

The conflict in the Broughton Archipelago is the latest skirmish in what is emerging as a global environmental battle over high- intensity fish farming. Environmentalists and fishermen in Chile have called for a moratorium on that country’s radically expanding salmon-farm industry. Conservation activists in Scotland, Canada’s eastern province of New Brunswick, and Maine are battling deadly farm-incubated diseases. Yet despite its environmental problems, salmon farming remains a booming business. As the production of wild fisheries continues to push its limits, aquaculture corporations are expanding existing farms and seeking out new sites, such as Iceland, for their “blue pastures.” Some companies are already looking past salmon. In Hawaii, for instance, the industry is keeping close watch on a pilot project to raise Pacific threadfin in open-ocean net pens. If the fish thrive, the industry’s next conquest may be the pristine waters of the South Pacific.

“Aquaculture has grown in huge bounds, faster than anything we’ve seen in traditional agriculture, and mistakes have been made,” says Rosamond Naylor, a senior fellow at Stanford University’s Center for Environmental Science and Policy who recently published a study of international fish farming in the journal Nature. “The question is, Can we make changes fast enough—before the damage becomes irreversible?”


Back when we envisioned the future in utopian terms, aquaculture was an integral part of the dream. As surely as we would all drive flying cars, wet-suit-clad cultivators would farm the seas and feed the world with their bounty.

It has not turned out as clean and easy as we’d imagined.

Modern fish farming traces its roots to Norway in the 1960s, when that nation’s wild salmon stocks crashed due to overfishing, overdamming, acid rain, and development. Inspired by the success of Danish trout farmers, salmon cultivators found Norway’s sheltered fjords ideal for farming salmon in ocean net pens.

European restaurateurs loved the farm-raised Atlantics, which allowed them to offer fresh salmon year-round. As demand increased, the industry expanded to Scotland, Ireland, and New Brunswick—anywhere that offered cheap access to cold, sheltered salt water. Meanwhile, problems began to crop up. In Norway, the growth of fish farming was marred by outbreaks of disease and parasites and the escape of millions of farm-bred salmon.

In the 1980s, Europe’s salmon-farming corporations sought to continue their westward expansion. They eyed two promising areas: Alaska and British Columbia.

Spurred by a politically powerful commercial fishing industry, Alaska outlawed salmon farming outright. British Columbia, on the other hand, welcomed the industry with open arms. In a province whose economy remains bound to extractive industries like logging, capitalizing on its marine resources seemed to make good economic sense.

“In the ’80s and early ’90s, Norway strengthened its environmental regulations in response to the problems they were having with fish farms,” says Lynn Hunter, a former Canadian member of parliament who now works on fisheries issues for the David Suzuki Foundation, a leading Canadian environmental group. “So a number of Norwegian farmers moved to Canada, where they wouldn’t face such a strict environmental regime. We got their bad apples.”

Today, Alaska’s wild salmon fishery ranks among the healthiest, best managed in the world. But British Columbia’s commercial fishing industry barely survives; in 1999, the wild salmon harvest was the lowest in 50 years. The Canadian government is trying to keep the industry afloat by buying out commercial fishing licenses and decreasing the number of boats in the water. Canada’s farmed-salmon industry, meanwhile, now ranks fourth in worldwide production. (In the United States, so far, salmon aquaculture has been limited to a few sites in Maine and Washington state.)

During the 1990s, salmon farming exploded around the globe. Stymied by environmentalists from further expansion in Canada, the industry headed to Chile, where farming corporations found cheaper labor and few environmental restrictions. The past decade also saw a frenzy of takeovers and mergers, as large companies—most notably Stolt-Nielsen, a Norwegian shipping company, and Nutreco, a Dutch conglomerate—bought smaller ones in order to achieve “vertical integration of the value chain,” industry-speak for the ability to hatch salmon fry, produce fish-food pellets, raise market-size fish, and distribute filets worldwide. The consolidation of the supermarket industry also fueled the merger mania; megagrocers preferred to contract with one supplier large enough to fill their freezers. This is how your Costco comes to offer farmed Atlantic filets at $3.99 a pound, less than half the price of wild salmon.

Farm-raised Atlantic salmon now rule the global premium fish market. In 2000, fish farmers raised 860,000 metric tons of Atlantic salmon—more than 1 metric ton for every wild salmon caught in the North Atlantic. Chilean-raised Atlantics are dumped so cheaply in the United States that they’re making it hard for Alaska fishermen to make a living. “When you’ve got Chilean filets hitting the Port of Miami at $2 a pound, raised by workers making $1.50 a day, that’s when the WTO hits home,” says John van Amerongen, editor of the Alaska Fishermen’s Journal.

For now, major environmental groups including the National Audubon Society and the Sierra Club recommend against eating farmed salmon because of the industry’s poor environmental record. Recognizing that aquaculture is likely to continue to grow, however, many environmentalists have also focused on moving the industry toward more sustainable practices. Two start-up companies in the Pacific Northwest are experimenting with a promising technology that uses solid-wall pens, which, though more expensive, could eliminate the problems of escaped fish and disease transfer to wild stocks. “Closed-containment systems,” says Rebecca Goldberg, a senior biologist with Environmental Defense, “are definitely a step in the right direction.”


Alexandra Morton doesn’t get too close to the fish-farm workers anymore. “They all know my boat,” she says. “I’ve had ’em moon me, call me all kinds of nasty names.” She gives a Stolt Sea Farm site wide berth, and then zips into a nearby cove and gets out her dip net.

Morton, who moved to the Broughton Archipelago nearly 20 years ago to study the habits of local orcas, became an anti- fish-farming activist in the late 1980s when the industry’s “seal scarers” drove the killer whales out of their traditional feeding grounds. To placate Morton, many of the farming companies turned off their alarms, and the orcas eventually returned. “It wasn’t just me,” she says. “Some farmers think they actually attract more predators—they call it the dinner-bell effect.”

Morton stands at the stern of her boat, dip net poised, waiting for two pink salmon smolts to swim within striking distance. A sea lice infestation broke out three weeks ago among this run of wild pinks, and Morton wants to check these two for parasites.

She nets the fish and releases them into a saltwater tank. Morton scoops one into her hand. “This one’s loaded,” she says. Parasites as small as sesame seeds scuttle across the fish’s tiny scales. Through a magnifying lens, the lice resemble tiny horseshoe crabs.

“He’s got a bunch of little ones hanging off his throat, too,” says Morton. Baby lice, hangnail-size, beard the fish. Over the next few weeks they will eat the salmon’s mucus, skin, and blood, killing their host. “This guy,” Morton says, “doesn’t have a chance.”

Her sampling indicates that wild smolts near fish farms carry far more lice than smolts caught away from the industrial sites. Morton fears that B.C.’s salmon may suf- fer the fate of Ireland’s fabled sea trout, which were devastated in the early 1990s by a fish-farm-incubated infestation of sea lice. British Columbia’s salmon farmers say lice hasn’t been a problem, but local fishermen believe the close-packed Atlantic salmon act as disease and lice hothouses. “They’re disease reservoirs stuck right on the migration path of wild salmon,” says fishing guide Chris Bennett. “You couldn’t dream up a better pathogen vector.” Fish farmers counter that they’re getting a bad rap. Their cages are sited—for environmental reasons—away from freshwater streams, in the high-saline waters where sea lice flourish. Of course you’ll find more lice around our farms, they argue; that’s where the saltier water is.

Morton disagrees. After documenting her latest lice survey, she calls an official at the government’s Pacific Biological Station research lab in Nanaimo, 150 miles south, and pleads with him to investigate the outbreak. “Look,” she says, “we’ve got a real problem up here.”

It’s a tough sell. The agency that runs the Biological Station, Canada’s federal Department of Fisheries and Oceans (DFO), is charged with both promoting fish farming and conserving wild salmon runs. That dual mission has led the dfo to turn a blind eye to the environmental threat posed by the farms. Earlier this year the auditor general, the Canadian government’s independent investigator, scolded the DFO for failing to enforce Canada’s Fisheries Act, the nation’s most sacred environmental law, when the law came into conflict with the salmon-farming industry.

Morton has allies, though. Using her data, a group of First Nations leaders calls a press conference in Victoria to denounce the fish farms and the government’s failure to regulate them. Dressed in full tribal regalia, they threaten to take action if the government doesn’t. “Our people are prepared to do what it takes to take care of our land, water, and resources,” says Percy Williams, chief of the Kwicksutaineuk-kwaw-mish tribe.

The DFO relents and dispatches a research vessel. By the time the boat reaches the archipelago, however, the run of infected pinks has passed out to sea.


As industrial salmon farming swept westward from Norway, it left a trail of environmental destruction in its wake. In Norway between 1989 and 1992, furunculosis-infected farm fish escaped and spread the disease to 550 other farms and 20 Norwegian rivers. In the 1990s, Infectious Salmon Anemia (ISA), a sort of hoof-and-mouth disease of the sea, ripped through farms in Scotland and New Brunswick. The New Brunswick Fisheries and Aquaculture Department ordered the slaughter of more than 1.2 million salmon in 1998 in an effort to control one ISA outbreak. That same year, ISA ravaged more than 11 farms in Scotland. In both cases, the disease eventually made its way into wild stocks. And just this past March, ISA spread into U.S. waters, infecting salmon farms in Maine.

“Whenever you raise organisms in dense concentrations, disease transfer happens a lot faster,” says James Karr, a professor of fisheries at the University of Washington. “When these fish are moved from one region to another, they may move disease that’s never been found in that area before.”

From the air, a salmon farm looks like a posh racquet club under floodwater. Farms usually float within a few hundred yards of shore, with the nets anchored by heavy cables. Hatchery-born fish are transferred to net pens when they’re 10 months old. In their new home, they’re fed pellets made of fish meal, fish oil, vitamins, and, as needed, antibiotics. Farmed salmon eat two to five pounds of protein for every pound of weight gained—protein that comes from small pelagic fish like anchovies, mackerel, herring, and sardines. Typically, 15,000 to 50,000 fish share a single pen, and 8 to 10 pens operate on a single site. Since the pens are open to the surrounding water, any waste generated by the fish flushes into the local ecosystem.

Farmers count on the tide to disperse net pen effluent, but the water often doesn’t flush it all away. A salmon farm of 200,000 fish releases an amount of fecal solids roughly equivalent to a town of 62,000 people. That’s a lot of fish poop, and it can create an oxygen-depleted “dead zone” on the seafloor under the net pens.

Then there are the jailbreaks. Everywhere the Atlantics go, they escape. In Norway, at least half a million farmed salmon escape from pens every year. Canadians worry about farmed fish displacing wild species. But in Norway, that battle is already over. The wild lost. Farmed Atlantics now outnumber wild salmon spawning in Norwegian rivers. “Salmon aquaculture,” the World Wildlife Fund said in a report issued last May, “now constitutes a major threat to wild salmon stocks—if not the major threat.”

On the Pacific Coast, it’s still an open question whether escaped Atlantics will displace native Pacific salmon. “Native salmon have evolved over thousands of years to live in this region,” says the University of Washington’s James Karr. “Their life histories are finely tuned to live in concert with other organisms in the region.” Each run of Pacific chinook, coho, sockeye, pink, and chum salmon knows how to survive in a specific spawning stream. When one stream goes haywire—perhaps it’s too hot, too low, or gets dammed—salmon in other streams survive. Farmed Atlantics are artificially bred to get fat fast and survive the close confines of a net pen. By allowing a homogeneous species of Atlantics to replace the diverse species of wild salmon, we’d be setting up an entire ecosystem for a horrendous crash. If that one species failed, all salmon would fail. And the reverberations of that would be felt up and down the food chain.


On days like this it’s almost not work,” Brian Wiley says as he pilots a skiff between salmon pens. The brilliant afternoon sun bounces off the emerald waters of Upper Retreat Pass. Wiley, a 42-year-old fishfarmer, gives an unannounced visitor a brief tour of his net pens, a site 20 miles east of northern Vancouver Island that’s owned by Stolt-Nielsen. He is buoyant; his eight-day shift ends in a couple of hours, and a company boat is coming to take him home to Campbell River for six days off.

Like any farmer, Wiley is proud of his product. “You get attached to ’em,” he says. “They’re your fish. That’s what’s cool about the work. They come in as smolts and stay with you for a year or two.”

This farm, one of Stolt’s 27 sites in British Columbia, holds 308,000 Atlantic salmon. Wiley and three co-workers pour 10 metric tons of food pellets into the pens each day and monitor the fish with underwater video cameras to see when they stop eating. “That way we don’t waste food,” says Wiley. “The pellets go for about $1,300 a ton, so you don’t want to waste it or kill any fish.”

When the fish near market size, farmers add astaxanthin, a pigment similar to beta-carotene, to their feed to give their gray flesh a salmony pinkish glow. (In the wild, asta- xanthin is synthesized by microalgae and passed up the food chain. Since farm-raised salmon eat only pellets, they must be dyed pink. The pharmaceutical giant Hoffman-La Roche, a leading supplier of astaxanthin to salmon farms, distributes a “SalmoFan”—kind of like a paint-store swatch—to let farmers perfect the desired hue.)

Brian Wiley and his colleagues are only a 10-minute boat ride from the island village of Echo Bay. But they don’t mix much with the locals. A fish tech is a lot like a logger—usually single, male, in his 20s or 30s, strong enough to handle the demanding physical work, willing to call in rangers to shoot seals and other predators, not overly concerned with the environmental nuances of the watershed in which he works. The farm’s floating bunkhouse has pretty much everything he needs: fully stocked kitchen, booming stereo, satellite TV.

“When I first heard about this job, I thought, ‘Oh great, feeding fish all day,'” says Wiley. “But you’ve got all kinds of stuff to deal with out here. We take plankton samples every day, do our environmentals, test the salinity of the water, the dissolved oxygen. Lot of stuff to know about.”

A lot of jobs did follow the fish farms to British Columbia. They just didn’t materialize so much in the archipelago, which bears the brunt of the environmental damage and ongoing risk. But back in Vancouver Island towns like Port Hardy, Port McNeill, and especially Campbell River, which bills itself as the Salmon Capital of the World, the salmon farms employ fish processors and farmers, and support businesses like boxing companies, net makers, trucking firms, construction contractors, and fuel docks.

“This industry is critical to our small communities,” says Anita Peterson, the spokeswoman for the Salmon Farmers Association. Not all small communities see the benefits, however, and the taverns of Port McNeill have seen heated arguments between pro-farming townies and anti-farming islanders.

Technology may ultimately help broker peace on the coast. Two companies, Future Sea Technologies (FST) of Nanaimo, British Columbia, and MariCulture Systems of Lake Stevens, Washington, are developing closed-containment pens that seal farmed salmon off from the outside water. These pens can cost up to one and a half times as much as conventional nets to install but pay off in faster-growing, healthier fish. And they have caught the attention of environmentalists and scientists. “Certainly the problems relating to escapement of fish and the waste disposal of fish would be largely or entirely solved with a closed-containment system,” says Rebecca Goldberg, the senior scientist with Environmental Defense.

A major problem, though, may not just be the initial cost: It may be that the systems appear too eco-friendly. Aquaculture corporations have become so embittered toward environmentalists that they’re leery of trying anything that comes with a seal of green approval. “Our customers are fish farmers,” says FST operations director Andy Clark, “but the environmental lobby says fish farming is the second coming of the devil—and they point to us as the savior. We’re caught in the middle.”

Moreover, many in the fish-farming industry do not acknowledge that there is a problem with open-flow pens. “With a closed system,” says Peterson of the Farmers Association, “you’re taking an absolutely prime growing environment and trying to artificially re-create it. Why would you do that?”


Aquaculture is not going away. We’re eating more fish even as the oceans and rivers run dry. Since 1989, the world’s commercial seafood catch has stagnated between 85 and 90 million tons. The United Nations Food and Agriculture Organization reported last year that most of the world’s fishing areas have “reached their maximum potential for capture-fisheries production, with the majority of stocks being fully exploited.” Meanwhile, aquaculture output has nearly tripled, from 12.3 million tons in 1989 to 30.9 million tons in 1998.

This is the paradox of salmon farming. “Aquaculture,” writes Stanford’s Rosamond Naylor, “is a possible solution, but also a contributing factor, to the collapse of fisheries stocks worldwide.”

The National Audubon Society, Environmental Defense, and the Sierra Club not only caution against eating farmed salmon; they in fact recommend eating wild Alaskan chinook and coho and other salmon that are sustainably fished.

Meanwhile, other groups including the David Suzuki Foundation and Living Oceans Society have begun campaigns to educate consumers about the health benefits of eating wild salmon, which, unlike farmed fish, contain no antibiotics, are not artificially dyed, and are higher in the omega-3 fatty acids that lower the risk of heart disease and breast cancer.

“The fish-farming industry has fed us a line about eating farmed salmon to protect wild stock,” says the Suzuki Foundation’s Hunter. “Actually, the reverse is true. If you purchase farmed salmon, you’re contributing to the risk to the wild fish.”

It’s a counterintuitive proposition: Eat the wild to save the wild. But if enough consumers vote with their purchases, fish farmers may start cleaning up their act. To that end, Hunter and her allies have come up with a slogan to beat the industry’s marketing machine. You can see it on her car’s bumper sticker as she drives away: Wild Salmon Don’t Do Drugs.


Our team has been on fire lately—publishing sweeping, one-of-a-kind investigations, ambitious, groundbreaking projects, and even releasing “the holy shit documentary of the year.” And that’s on top of protecting free and fair elections and standing up to bullies and BS when others in the media don’t.

Yet, we just came up pretty short on our first big fundraising campaign since Mother Jones and the Center for Investigative Reporting joined forces.

So, two things:

1) If you value the journalism we do but haven’t pitched in over the last few months, please consider doing so now—we urgently need a lot of help to make up for lost ground.

2) If you’re not ready to donate but you’re interested enough in our work to be reading this, please consider signing up for our free Mother Jones Daily newsletter to get to know us and our reporting better. Maybe once you do, you’ll see it’s something worth supporting.

payment methods


Our team has been on fire lately—publishing sweeping, one-of-a-kind investigations, ambitious, groundbreaking projects, and even releasing “the holy shit documentary of the year.” And that’s on top of protecting free and fair elections and standing up to bullies and BS when others in the media don’t.

Yet, we just came up pretty short on our first big fundraising campaign since Mother Jones and the Center for Investigative Reporting joined forces.

So, two things:

1) If you value the journalism we do but haven’t pitched in over the last few months, please consider doing so now—we urgently need a lot of help to make up for lost ground.

2) If you’re not ready to donate but you’re interested enough in our work to be reading this, please consider signing up for our free Mother Jones Daily newsletter to get to know us and our reporting better. Maybe once you do, you’ll see it’s something worth supporting.

payment methods

We Recommend


Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.


Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.