Veteran gillnetter Pete Knutson has hauled countless salmon out of Puget Sound since he began plying the local waters in 1972. So imagine his surprise one night in 1992, when up came a dozen Atlantic salmon—easily distinguishable from the native species by the large dark splotches on their gill covers. As their name suggests, these fish should have been cruising North Atlantic waters; Knutson caught them in Seattle's Elliott Bay.
With native salmon on the wane, you might think Knutson was happy to find another breed of salmon to catch. You'd be dead wrong. When he mentions Atlantic salmon, Knutson's voice takes on the same disgusted tone Seattleites use to discuss transplanted California real estate developers: "They're like goldfish."
Knutson and his fellow adepts regard Atlantics as inferior because they come not from nature but from floating fish feedlots—one of the net-pen "farms" around Puget Sound. Salmon farmers raise Atlantic salmon because they grow faster and fatter in captivity and are more docile than our native salmon.
Aquaculture proponents tout salmon farming in general as an economic opportunity for depressed coastal communities. The industry's critics, however, argue that salmon aquaculture has created a worldwide glut of salmon, lowering profits and stealing market share from commercial fishermen. "They've really pushed the entire [commercial salmon] industry to the brink," says Knutson, who is now a full-time sociology professor and only part-time salmon fisherman.
But commercial competition is the least of opponents' concerns. Fish farms are messy operations that dump waste into Puget Sound, and escaped fish are like "smart bombs," says Knutson, delivering disease, predation, and competition "right into the bedrooms of wild salmon." If there's one thing our already hammered wild fish don't need, say critics of the farms, it's another salmon-killing industry. But the farms are well entrenched here, and they're looking to expand.
Breeding Pestilence and Pollution
"[Salmon farming] will lead to the destruction of wild salmon here," says David Ellis, executive director of the British Columbiabased Fish for Life Foundation, a strident antisalmon farming group. A former commercial fisherman turned fisheries consultant and wild salmon advocate, Ellis has led the charge against salmon farming in British Columbia, which has as many as 149 salmon net pens floating off its coast. His 1996 net loss report for the David Suzuki Foundation described a host of ecological impacts and risks from farming Atlantic salmon, including the generation of huge amounts of fish feces, disease transmission, antibiotic and chemical use, and conflicts with marine mammals. Pens are typically 30 by 30 meters, 20 meters deep, and made of steel with nylon mesh. A farm may contain as many as 26 pens surrounding a catwalk—an arrangement making it relatively easy to feed, monitor, and harvest the fish. Larger farms hold several hundred thousand salmon at a time.
Worldwide, salmon aquaculture is rapidly expanding, with farm production in 1997 outpacing wild salmon harvest for the first time—a consequence both of industry growth and declining wild runs. The opposite trends are no coincidence, according to Ellis, who is convinced that wild stocks suffer wherever salmon farms are established. Norway's wild salmon and sea trout have withered as diseases like furunculosis and sea lice have spread from salmon farms to native fish. Norway's plight is so desperate, in fact, that officials there have poisoned more than 24 rivers with the piscicide rotenone in hopes of cleansing them of farm-bred diseases. Likewise, the collapse of Ireland's west coast sea trout fishery and the decline of Scotland's salmon and sea trout populations have been linked to diseases spread by marine net pens.
"The greatest danger by far is disease," says Ellis. Atlantics host pathogens for which Pacific salmon lack immunity, he says. Exotic diseases have the ability to spread rapidly among the natives just as smallpox decimated many American Indian communities with the advent of European immigration. Salmon farms also amplify indigenous fish diseases—native pathogens can multiply in the stressful, crowded pens and eventually infect wild salmon swimming by. Ellis confirmed seven major outbreaks of Pacific Coast salmon diseases at BC salmon farms in the past decade. In at least two instances documented by orca researcher Alexandra Morton, outbreaks spread to local salmon swimming home to a community enhancement hatchery on the Broughton Archipelago. Following a 1991 outbreak of the bacterial disease furunculosis at a nearby net pen, returning hatchery fish developed the disease and mortality jumped from 3 percent to 28 percent. Two years later, an outbreak of a unique strain of antibiotic-resistant furunculosis also showed up in the hatchery fish, whose migration route brought them past the infested farm.
British Columbia's problem is our problem, too, as Puget Sound salmon regularly swim past fish farms in the Strait of Georgia on their migration home.
Escapes are inevitable, says Ellis, boosting chances that farm-reared diseases will infiltrate local stocks. In Norway, approximately 1.3 million farm fish escape each year. British Columbia farms lose between 60,000 and 120,000 Atlantics annually. Escapes also raise the threat of Atlantic salmon establishing themselves in local watersheds and competing with already stressed local fish.
Predators see salmon farms as irresistible all-you-can-eat dives with free admission, and their constant visitation sets up seals, dogfish, great blue herons, kingfishers, and other birds for retribution from salmon farmers. Harbor seals cause more than $10 million in annual losses to the BC farmed-salmon industry, and its farmers regularly kill problem seals. In the US, there were 51,000 authorized bird kills at US aquaculture operations between 1989 and 1993. "When you put a farm into a wild environment, suddenly all the wild creatures become weeds and pests," warns Pete Knutson.
