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A Case Against Open-Net Salmon Farms

A Case Against Open-Net Salmon Farms
The harvested salmon began as fertilized, eyed eggs purchased from the West Coast. They were hatched into larvae in trays at the Freshwater Institute, and raised into 8- to 10-pound adults, four to nine months faster than in ocean pens.

[See also "Futuristic Fish Farms" in the June-July 2014 issue of FLY FISHERMAN. The Editor.]

"We have all the science we need now to prove that open-net-pen farming of Atlantic salmon is not working---dozens of studies from recognized scientists that document the threats of repeated outbreaks of disease in the farmed fish, the damage to wild salmon populations, and the pollution to the environment caused by the farms. We have lost the wild salmon in most of the New Brunswick and Nova Scotia streams flowing into the Bay of Fundy, where the largest number of open net-pen farms exist. The Bay of Fundy wild-salmon populations began their decline coincident with the growth of open net-pen salmon farming in the '80s and '90s. The disappearance of wild salmon in the Magaguadavic River in New Brunswick is a science-proven prime example of the effects nearby open net-pen salmon farming can have on a river's wild-salmon population. They disappeared.

"No future open-net-pen farming operations should be licensed in Eastern Canada. The Atlantic Salmon Federation supports the farming of Atlantic salmon, but primarily in land-based, closed-containment systems, and perhaps in small, tightly regulated and closely inspected, net-pen operations similar to those operating on the coast of Maine.

"We urge the Canadian government and its Department of Fisheries and Oceans (DFO) and the open-net-pen industry to join with us, in making this transition happen. We all know now that this is the future of commercial Atlantic salmon farming, which is here to stay but in operations that will not destroy wild Atlantic salmon or the environment in which they can thrive."

Bill Taylor,


The Atlantic Salmon Federation

August 24, 2013

The Freshwater Institute brought 20 metric tons of Atlantic Salmon to market at a competitive price, little impact to the environment, and use of 99 percent recycled fresh water.

Can wild Atlantic and Pacific salmon be saved from extinction if floating open-net-pen fish farms are replaced by chemical- and disease-free, closed-cycle farms on land? The idea sounds too good to be true to an editor/writer who for more than 30 years has been following the first-promising and highly promoted birth of industrial floating fish farms from Norway, to Scotland, Ireland, the Faroe Islands, the Canadian Maritimes, British Columbia, and Chile. It has been a failed promise. The new hope is land-based, closed-containment systems for fish production.

In a nutshell here's why floating open-net-pen Atlantic salmon fish farms have failed, despite providing most of the popular retailed Atlantic salmon to the public in the past two decades: The farms have: spawned many wipe-outs of their own products due to massive outbreaks of infectious salmon anemia (ISA) in the Bay of Fundy and Chile; lost the support of the public in British Columbia due to a recent decline of the Fraser River sockeye runs; lost the support of the public in eastern Canada as the wild-salmon runs of the Bay of Fundy disappeared; lost the support of a public that now knows of the dangerous chemicals used to control massive sea-lice infestations in net-pens; lost the support of the public that views with alarm reported attempts by the British Columbia Department of Fisheries and Oceans (DFO) to throttle or ignore international peer-reviewed science that shows open-net-pen fish farming severely threatens wild fish and the environment. Incidentally, the Norwegian government has advised pregnant women to not eat farm-raised Atlantic salmon more than twice a month.

The harvested salmon began as fertilized, eyed eggs purchased from the West Coast. They were hatched into larvae in trays at the Freshwater Institute, and raised into 8- to 10-pound adults, four to nine months faster than in ocean pens.

Virtually all the open-net-pen-raised Atlantic salmon produced in North America are raised in Canada--either in eastern Canada or British Columbia (with the exception of Maine)—and until recently all were raised in adult-stage net-pen "grow-outs" located in saltwater estuaries.

Canada Explores Net-Pen Alternatives


A March, 2013 "Report of the Standing Committee on Fisheries and Oceans" to the First Session of the 41st Parliament outlines what many in Canada (and the U.S.) are viewing as a possible solution to the growing net-pen problems and the controversies they have spawned.

The Report is the second of its kind conducted by the Committee On Open-Net-Pen Farming for the government. The first, conducted in 1999-2003 and called "The Federal Role of Aquaculture in Canada", contained just one recommendation pertaining to closed-containment aquaculture. But the current 2013 Report says: "As a result of increased scrutiny on the environmental impacts of the aquaculture industry, closed-containment technologies have become a major focus of aquaculture research and development. The fact that this report focuses entirely on closed-containment aquaculture indicates how much the dialogue has changed over the last decade."

Here, in part, are some of the 2013 Committee findings.

"Aquaculture accounts for 14% of total fish and seafood production in Canada by land volume, or 35% by value. Canadian aquaculture production includes several species of salmon, trout, mussels, and oysters. Salmon farming is by far the largest industry, accounting for 63% by volume, or 75% by value of total Canadian production, the vast majority of which is Atlantic salmon. In 2010 Canada raised 101,385 tons of farmed salmon, for a total value of $690.9 million. The same year Canada exported 80,000 tons of salmon, 98% of which was Atlantic


"The salmon aquaculture industry expanded dramatically over the course of the 1980s and 1990s. The Canadian industry experienced some declines during the early to mid-2000s, due largely to disease outbreaks and global market factors. While initially made up of many smaller companies, the salmon aquaculture industry has undergone considerable consolidation and vertical integration in Canada, with the vast majority of production now raised by just four companies in each of British Columbia, New Brunswick and three companies in Nova Scotia. There are approximately 130 sites (80 active at any given time) in British Columbia, 90 sites in New Brunswick and 15 in Nova Scotia. Newfoundland and Labrador had 12 sites as of 2010 but is experiencing significant growth in this sector.

"Globally, Canada produced about 7% of the world's farmed salmon in 2009, ranking fourth in terms of salmon aquaculture production, behind only Norway, the UK, and Chile. In 2010 Canada exported approximately 78,000 tons of farmed salmon to the U.S. (approximately 77% of our total production) for approximately $525 million. Canadian farmed salmon was also exported to Japan, France, Taiwan, and other countries to a lesser degree.

"There has been no significant growth in salmon aquaculture production in Canada over the past decade, with 2010 production volumes still slightly less than they produced in 2001. This is attributable to a variety of factors, including a decline in world prices for Atlantic salmon, a moratorium on new salmon farm licenses in British Columbia, and new farm siting and environmental management requirements. Industry representatives, however, have told the Committee that they believe the time is ripe for expansion again, as American demand is growing at a rate of 3% to 5% a year.

"In conventional net-pen operations, salmon spend about one third of their lives in closed-containment systems at a hatchery. When the salmon smolts are approximately 12cm in length or 100g (12 to 18 months after hatchery), they are transferred to net pens in the ocean, where they stay and grow for an additional 18 to 24 months before being harvested. Atlantic salmon are considered to be harvestable size when they are approximately 4.5 to 6 kg.

The first successful U.S. experiment with commercial closed-containment aquaculture occurred in 2013 at the Freshwater institute in Shepherdstown, West Virginia. Land-based farms like these may save our oceans—if consumers support them.

"Closed-containment aquaculture refers to a number of technologies that seek to isolate the rearing environment from the natural environment in order to reduce or eliminate the interactions between the two. Not all types of closed-containment systems are entirely separated from the natural environment, and as a result some are more "closed" than others. While a number of technologies and systems have been designed and piloted over the years, the two most relevant technologies that seem to have emerged for the Canadian salmon-farming industry are ocean-based, solid-wall containment systems and land-based recirculating aquaculture systems (RAS).

Ocean-based, Solid-wall Systems

"Ocean-based solid-wall containment systems consist of solid-wall fiber and foam composite tanks ranging in size from 3000-cubic meters that float at the surface of the water. The water intake allows water to be drawn into the tank from varying depths (which provides for control of water quality and temperature). Supplemental oxygen is pumped into the tank to maintain optimal dissolved-oxygen levels. Waste feed and feces are filtered out via a drain at the bottom of the tank and pumped away with the expectation that it could be treated for disposal on land as fertilizer, while the remainder of the relatively clear water is allowed to overflow over the top of the tank into the surrounding waters.

"Such systems are not completely closed because the intake water is not treated before entering the tank and water from the tank is released back into the ocean. Nevertheless, the system is successful in removing 90% of settleable wastes, which in an open-net-pen aquaculture system would otherwise settle to the ocean floor or be dispersed by ocean currents. In addition, due to the solid walls, the system provides for separation of wild and farmed populations and reduces the risk of escapees and predation."

The report does not mention that the floating, closed-containment system is subject to destruction by storms. It describes land-based recirculating aquaculture systems (RAS) and points out that:

"Although there are not yet any commercial-scale closed-containment systems raising Atlantic salmon anywhere in the world, closed-containment technologies already play a significant role in parts of the farm-raised Atlantic-salmon growth cycle, both in Canada and abroad. The Committee heard from Marine Harvest that their salmon spend approximately the first third of their lives in closed-containment RAS (up to the point where the smolts are transferred to the net-pen sites). In addition, half of their broodstock is raised entirely in a dedicated RAS facility. These practices are now common in the industry in order to exercise greater control over environmental factors and reduce business risk."

The Committee's report describes the prime obstacles to converting open-net-pen aquaculture to closed-containment RAS systems as cultural and economic costs.

[Note: The report mentions only in passing the glaring conflict of interest the country's Department of Fisheries and Oceans (DFO) has in accomplishing its foundational mission of protecting the wild fisheries of Canada while promoting and attempting to regulate an industry that is threatening and, critics contend, destroying those very national treasures. In 2009 Canada took control of ocean finfish regulation away from the British Columbia DFO after it was sued in a private lawsuit for its lack of effective oversight on its mission to protect wild salmon stocks. A BC Supreme Court judge ordered that under law the federal--not the provincial--government is responsible for finfish management and fisheries protection and ordered an end to BC's regulation of ocean-based finfish aquaculture.

Since the 2013 report was submitted, two on-land RAS operations have begun raising and selling Atlantic salmon and Arctic charr, both owned by Sustainable Blue (, one at Truro and another at Centerville, Nova Scotia.

The report makes clear that completely closing ocean open-net-pen farms is not in the cards. Canada would have to overlook a large political problem: closing an economically important, profitable, labor-important industry, thus losing jobs in two job-poor regions, and replacing them with smaller, less labor-intensive and capital-intensive RAS operations. The committee report also points out that capital for RAS systems is hard to come by because private banks are not interested in funding the high-risk $30 million upfront capital costs per RAS unit.

What this means is that Canada's close governmental connection to commercial salmon farming (primarily in promoting and regulating it) must of political needs continue, and will probably involve cooperative public/private financing if open-net-pen farming is to come onshore or dramatically change its operations in the sea to be more environmentally friendly. ASF President Bill Taylor believes that private capital is leading the way in changing commercial salmon-raising from open-net-pen to RAS operations. The privately-funded Sustainable Blue is the first example in North America, but private commercial RAS salmon systems are running in France, Norway, and soon at a 1000-ton commercial system under construction in remote northern Denmark. The world's largest onshore salmon farm (owned by FishFrom) is under construction at Dunkeld, Scotland, with a projected production of 3,000 metric tons of salmon. China also raises Atlantic salmon in closed-containment systems.

How a RAS Works

Last year the Conservation Fund's 20-year-old Freshwater Institute in Shepherdstown, West Virginia, partnering with the Atlantic Salmon Federation--and partially funded by the U.S. Dept. of Agriculture and private endowments--finished a two-year experimental project growing Atlantic salmon smolts in fresh water to market size (8-10 pounds). The salmon (20 metric tons) were raised in an indoor recirculating aquaculture system (RAS) that recycles water for the fish and captures 98% of the waste material.

It was the first American project of its kind to successfully produce Atlantic salmon to market size in a closed-containment system---and, in 2013, send them to market. On March 18, 2013 the Namgis First Nation tribe opened the first western Canada commercial RAS Atlantic-salmon farm on northern Vancouver Island using the Freshwater Institute's technology and funding from Canada's Tides Foundation, with a projected annual production of 470 metric tons of Atlantic salmon.

[Editor's note. An ocean-based, floating, partially closed, solid-wall system was built near Campbell River on Vancouver Island, managed by AgriMarine in cooperation with the not-for-profit Middle Bay Sustainable Aquaculture Institute. It was scheduled to open operations in summer 2012, but a severe storm damaged its demonstration tank. The other three tanks have been redesigned and the operation is now operating.]

The RAS operations offer the following benefits over net-pen ocean salmon farming: Little use of and no discharge of antibiotics and pesticides into the marine environment; no amplification of or spread of sea lice to the environment; the ability to contain and control bacteria and viruses and prevent them from entering the marine environment; no discharge of fish waste into the environment; no fish culling and entanglement of marine mammals and birds in nets; no escape of nonindigenous species into the marine environment—thus avoiding invasive, competitive inbreeding with native species of salmon such has happened in the Bay of Fundy.

The production benefits over net-pen aquaculture include: faster (year-round) growth; less feed needed (1 pound of feed produces one pound of salmon, about the same food/fish ratio as ocean net-pen farmed salmon); no losses of fish due to disease (infectious salmon anemia [ISA] and others); no losses due to parasites like Kudoa—soft-flesh syndrome—and sea lice; the ability to use feces as aquaponics recycle-system fertilizer; the ability to locate farms near markets. Per-pound-of-fish production costs are projected close to, or below, net-pen per-pound costs ($1.80). But capital RAS start-up costs are higher: $30-million per farm-unit construction versus $10 million per net-pen operation. The taste and meat quality of RAS salmon are as good as net-pen aquaculture salmon, according to Canadian restaurateurs who have served them.

The science-based RAS systems forestall all the documented environmental threats to wild Atlantic salmon--and the sea--that sea-based, open-net-pen systems brought to the salmon estuaries and rivers of the Northern Hemisphere and Chile. And they do so at much lower crop-loss and environmental costs to taxpayers. Their carbon footprints favor RAS systems, which do not have the bottom-sediment methane emissions and eutrophication problems produced by net-pen excrement and chemicals.

Land-Based, Closed-Containment Fish Farming

According to the Conservation Fund Freshwater Institute's Director of Aquaculture Systems Research Steven T. Summerfelt, Ph.D. and Brian J. Vinci, Ph.D., Director of Engineering Services, the present and future of land-based closed-containment aquaculture is proven and inevitable. He says:

"U.S. farmers are first in cattle and poultry production in the world and second in hogs, with total terrestrial production of nearly 38 million tons per year, but the U.S. produces less than 1% of this biomass using fish farming.

"Simply put, fish-farm expansion in the U.S. has been constrained by limited water resources, site access, and regulatory limitations. Due to these constraints, to create significant new production we must develop technically advanced, environmentally compatible, and economically sustainable, production systems and techniques for species with strong market demand, such as Atlantic salmon.

"The U.S. consumes approximately 300,000 tons of farm-raised Atlantic salmon annually, but farms less than about 20,000 tons. Arguably, all fish farms in the U.S. are CAFO's (concentrated animal feeding operations). However, only pond systems and land-based, closed-containment systems can still be widely sited and permitted in the U.S. due to our water and regulatory constraints. Land-based, closed-containment systems use water recirculation technologies that continuously filter and recycle as much as 99.8% of the water flowing through the system and have only minimal direct hydraulic interaction with the environment. During the recycling process, land-based, closed-containment systems can control and capture 98-99% of fish waste solids and phosphorous, plus much of the nitrogen.

"Therefore, large-scale fish-farm operations employing these technologies can be located in areas adjacent to major U.S. markets or with minimal siting restrictions, limited water resources, strict discharge regulations, or cheap electricity. In addition, land-based, closed-containment systems allow for much greater control of the rearing environment than ponds, flow-through net-pen, or floating-tank systems. Water temperature and quality can be maintained at optimum levels; multiple barriers can be used to prevent fish escapement; protection from storms, wildlife, and vandals can be achieved; implementation of bio security strategies can improve fish welfare by minimizing disease and result in healthy fish and negligible use of antibiotics or chemicals.

"Nutrients can be concentrated into much smaller volumes, resulting in a manageable effluent (one that can be disinfected) and significantly less waste discharge to the environment; and phosphorous, nitrogen, carbon, and nutrients can be recaptured for reuse as a soil amendment, to feed vegetables and herbs in large-scale aquaponics systems, or for methane productions."

The authors describe the success of their Freshwater Institute Atlantic salmon RAS at Shepherdstown. Similar land-based, RAS aquaponic systems in operation throughout the U.S. (See also Blue Ridge Aquaculture, the largest producers of tilapia in the U.S., are proving that aquaponics is the future of industrial fish farming, and they demonstrate the science-based technological promise that may save wild Atlantic salmon from further decline. The Summerfelt-designed RAS is an elegant example of biochemical/technological innovation, proof in operation that science-based, reliable onshore commercial aquaculture is here. It is now the confirmed present and future of safe aquacultural fish products in North America. And it is the technology that should save our wild salmon. However, as Summerfelt points out, the future of RAS systems in the U.S. depends on large-scale (40- to 100-ton) salmon productions being built and showing that they can be profitable.

How the System Works

This text can be used with tank illustration.

The Institute system uses only fresh water, drawn (from 5 to 30 gallons per minute depending on the season) from a karst limestone spring creek on the property and fed into a hatchery house containing a 40,000-gallon circulating growing tank with a 30' diameter and 8' depth, where thousands (90 to 120kg/cubic meter density in the tank, compared to 25kg/cubic meter density in a net-pen) of healthy 8- 10-pound Atlantic salmon swim, knifing into the cool (58 degrees F.) circulating current and occasionally leaping, perhaps showing natural pre-spawn competitive exuberance. The population is mixed males and females. The males are harvested early—prior to maturation--due to lower-than-premium (pale in color) fillet quality. Most commercial net-pen salmon operations use exclusively female salmon to eliminate problems with sexually early-maturing males.

The silvery adult salmon (some pale and some dark in color) are near harvest size (August 5, 2013). They were hatched from Cascade-strain fertilized (eyed) eggs purchased from American Gold Seafoods on the West Coast and shipped chilled overnight to the hatchery. The two-year egg-to-adult growing cycle—4 to 9 months shorter than the net-pen salmon growth cycle—begins when the eggs are hatched into larvae in trays (1 month hatching and incubation), and raised for 6 to 7 months in a larval/juvenile rearing system, where they are photoperiod-manipulated to induce smoltification. Then they are moved to a cleaner, freshwater "depuration" system for 7-10 days, which allows their systems to cleanse of any bacteria that can cause a musty flavor in the fillets from the natural "salmon taste" that buyers favor. Then they are raised for 3-4 months to post-smolt size.

The post-smolts are finally introduced to the large "grow-out tank," where they grow swiftly, fed fish pellets three to four times a day, to near 3-kilogram size in 6 months and finally, in the last 6 months, to from 4- to 5-kgs. Then they are euthanized instantly--to prevent build-up of lactic acid in their flesh--by a cranium stunning piston.

The fish are iced down and shipped swiftly to Albion Seafoods in British Columbia, where they are processed and marketed. The most expensive cost in the whole process is the fish pellets (made from ground-up menhaden and other saltwater baitfish.)

Summerfelt says his operation can grow the salmon 4-9 months faster than net-pen operations due to its ability to control the "culture environment," particularly the water temperature.

The fish excrement is separated at the bottom center-drain of the tank, which carries a small flow to a settling device (a radial flow settler). Further flow-solids filtration of the entire recycled flow takes place in a microscreen drum filter. The nutrient-rich wastewater separated from the fish system is ready for use in growing various lettuces and other veggies popular with the rapidly expanding health-food market and for reuse in the closed cycle. (The Institute plans to add an aquaponic veggie garden in the near future; the fish feces is currently taken to a municipal waste plant. After solids removal is complete, the filtered flow is then pumped through a fluidized sand biofilter for conversion of ammonia to the final product in the nitrogen cycle---nitrate.

End illustration caption text

Summerfelt's system is entirely closed, except for a small amount of treated wastewater, tested as clean under a National Pollution Discharge Permit. It is entirely disease free, never having experienced an outbreak of ISA or any other salmon disease. And it has never lost a salmon (smolt or larvae) to nearby streams. As Senior Research Associate John Davidson III says, "The system engineering design was created here by Dr. Summerfelt and our engineering team through extensive technological research. It's completely closed, and it can be recreated anywhere on land. All it needs is clean, cold water."

The Canadian Standing Committee comments:

"Compared to open-net-pen Atlantic salmon farming, a land-based RAS is a relatively high-tech and high-cost endeavor. To offset these additional costs, however, RAS systems offer a number of potential advantages, including faster growth rates, and the potential to stock (in tanks) salmon at three to seven times the density possible in conventional net pens."

The net-pen industry says it will take an area the size of "8,000 football fields to put the net-pen operations on land." The ASF says it would only take 75 to 150 football fields to grow 30,000 tons of Atlantic salmon in RAS operations at a production cost of $1.80/pound, the same per-pound cost as net-pen salmon. The RAS operations can use either salt, brackish, or fresh water. And the same (in fact any) water can be cleaned, recooled, and re-used, again and again.

Note to Editor: Online text can begin here.

ASF President Bill Taylor is adamant about the modern situation confronting wild Atlantic salmon:

"We must immediately halt all construction of new net-pen operations in the Bay of Fundy. We have overwhelming evidence—30 to 40 peer-reviewed studies by internationally recognized scientists--that prove the disease, sea lice, and environmental impacts of the open net-pen operations and the deleterious effects they have on wild-salmon populations. There are no scientific studies that show there are no threats posed by open net-pen aquaculture. However, while infectious salmon anemia (ISA) is rarely seen in wild salmon, it reaches epidemic proportions when thousands of fish are confined within small spaces. The same is true of sea lice. Open net-pen cages are the perfect breeding grounds for both. I think this should give everyone an understanding that results in deep concern with the reality of fish farming practices and fish health regulations.

"DFO must join and support us in this. They must again take up their foundational mission of protecting wild fisheries across Canada and stop promoting open net-pen farming in our waters. It's a glaring conflict of interest In effect, DFO is the fox guarding the hen house."

Taylor says that open net-pen operations can exist but not as is, "only if they are small (as in the Maine net-pen operations), managed under science-based, tight regulations, and inspected, and if their records are open to inspection by both the government and the nongovernmental organizations. And they must report environmental costs to the public in their cost accounting."

Bay of Fundy net-pen operations currently meet none of Taylor's criteria. (In mid-July 2013 three separate ISA outbreaks in southern Newfoundland [Bay of Fundy] open net-pen operations killed over 500,000 salmon. The operations will be reimbursed by the DFO for their losses. Taylor contends there should be "no reimbursements, or other taxpayer financial support, for such obvious poor performance."

Taylor also points out that while open-net-pen aquaculture is a prime cause of wild-salmon decline in the Bay of Fundy, there are other possible contributing factors, including a rapid, and large, increase in the seal populations from Labrador to southern Nova Scotia, possibly in response to the explosion of net-pen aquaculture, or due to the rapid increase in shark populations (also apex fish-eating predators) in the Bay, perhaps influenced by global warming of the waters.

The ASF has started a genetic banking program to preserve the unique river genetic strains of wild salmon, but more work in this area needs to be done. To say the least, most Atlantic salmon streams and runs in the Gaspe and the Maritime Provinces are not scientifically monitored by the government(s).

Can the Bay of Fundy wild Atlantic salmon runs be restored? Taylor warns: "Only if the DFO first changes its support (financially, operationally, and politically) of open-net-pen aquaculture, restores its preservation-of-wild-salmon mission, and becomes more open and factual in its work. Only if it provides strong financial support to nongovernmental science-based research on the broad systemic causes of the salmon decline. Only if the DFO provides substantial financial support for projects that prove effective in reversing those causes. Only if the public supports tax increases ($10-$20 per household annually in eastern Canada) to fund those projects. Only if the DFO becomes more open to public demand for preservation and restoration of wild Atlantic salmon.

"Large commercial Atlantic salmon RAS operations are coming within the next year or two. The Sustainable Blue operation in Nova Scotia could reach the 1000-ton plateau in a year or two and we are hearing about other RAS operations under study for Maine and the Maritimes.

"The government will drag its feet in the sea-change that is coming. The change will be driven by private investment. The net-pen industry knows it is coming. They are tired of the bad news about their industry and they can see the conversion is near. The industry wants to do the right thing. . .to make the change."

To increase public understanding of the salmon decline, and support for conservation and restoration, the ASF has initiated a "Clean Up Salmon Farming" informational program in Nova Scotia, with roadside billboards explaining the problems and solutions. A recent ASF polling study showed that, while most respondents know little about the wild-salmon decline, some 80% of eastern Canada respondents believe that wild Atlantic salmon are a cultural ecosystem treasure worth preserving and restoring, and they will pay for salmon restoration programs if they are convinced the programs will be 80% or more effective.

Open-Net-Pen Salmon Farming Arrives

In the '80s and '90s, as the wild Atlantic salmon runs declined, the newly developing estuary net-pen-farming methods in Norway, caused fast-growing Atlantic salmon to quickly become a keystone fish-farming species of the new industry. (Warm-water species such as tilapia, catfish, and shrimp experienced the same explosive commercial-farming growth, primarily in freshwater ponds and rivers).

Farming fish, had been an artisanal aquaculture practiced virtually worldwide for millennia (especially in China and Southeast Asia), but in the past four decades it has blossomed into a new industrial-intensive aquaculture worldwide, in both freshwater and salt, amounting to an estimated 60 million tons of farm-raised fish, roughly half of all fish now sold worldwide.

Environmental Controversies

Unfortunately the growth of net-pen aquaculture has not been without environmental controversies, including scientific discoveries of man-made chemicals such as PCBs, mercury, and pharmaceuticals in farmed fish, the well-documented spread of fish-killing sea lice in regions where Atlantic salmon are farmed, the documented interbreeding of escaped farm-raised salmon with wild salmon in spawning rivers (causing debilitating genetic changes in the wild fish), and the spread of infectious salmon anemia (ISA) from Norway to Scotland, Ireland, Eastern Canada, the Faroe and Shetland islands, and Chilean fish farms, where a biological and economic wipe-out of 75% of net-pen farms (a $2 billion hit to the industry) has occurred since 2008. [See more on ISA and other fish viruses below, including the Canadian and U.S. responses to them.]

Briefly, here are facts scientists have discovered that help to describe the scope, documented threats, and latest hope of this highly productive and rapidly growing world industry.

*By 2008 over 70 percent of world saltwater fish stocks (including species in all levels of the food chains) had been fully exploited or over-fished.

*By 2008 the aquaculture industry produced about 40% of the seafood eaten worldwide; by 2013 that figure had reached 50%, growing faster than any other agricultural industry.

*China is the world leader in fish-farm production, producing some 115 to 120 billion pounds of farm-raised fish (mostly land-based), shipped worldwide but mainly consumed by the homeland Chinese.

*According to the Environmental Defense Fund "Global fisheries exports now earn more revenue than any other traded food commodity", a $78-billion worldwide industry.

*Most concerns with sea-based fish farming are caused by: severe crowding of thousands of fish (mostly Atlantic and Pacific salmon) in an artificial environment; the effluent they create and its effects (short term and long) on the environment; the chemicals used to treat pests and diseases among the fish; escapee fish and their proven in-breeding effects on wild fish, particularly Atlantic salmon; and the possible chemical threats to humans who consume farm-raised fish. (As examples, net-pen fish and shrimp are raised in the Mekong River in Vietnam, one of the most polluted rivers in Southeast Asia, and sold into U.S. markets. Chinese rivers are also heavily polluted, and fish are raised in them--often using human waste and pharmaceuticals--and exported, to the U.S. without much federal regulation, accurate source tracing, or effective inspection.)

*Scientists warn that it takes many pounds of forage fish (menhaden, for example) to produce one pound of farmed fish--some farmed species are herbivores while others, including salmon, are carnivores. According to a San Francisco Chronicle article in 2008, it takes 26 pounds of feed (chopped squid, blue mackerel and sand eel) to produce 1 pound of bluefin tuna. Over 40% of all global seafood is ground into feed for fish and other animals, up from 7.7% in 1948, according to research from the UBC Fisheries Centre. In Norway it takes 5 kilograms of forage-fish pelletized food to produce 1 kilogram of farmed salmon.

*Coastal areas worldwide have experienced habitat and ecosystem changes to accommodate fish farms, including elimination of mangrove habitat in Thailand, China, and Vietnam to create shrimp and other farms. The World Resources Institute estimates that nearly half the land used for fish farms in Thailand was formerly used for rice paddies.

*Researchers report that in estuary areas of Chile, the Bay of Fundy, eastern Ireland, western Scotland, and British Columbia where fish farms exist the sea bottoms experience severe declines in bottom life, caused by fish excrement and chemicals, in effect turning them into low-oxygen aquatic deserts. In the case of Chile, the dead bottom is also carpeted with abandoned farming junk.

*Chile is the worst case of a farmed-salmon wipe-out: Since 2008 three quarters of the country's farmed-salmon stocks have been destroyed by ISA, brought on by over-crowded net-pens and by massive use of antibiotics (600 times the amount used per unit area in Norwegian fish farms) to, the farmers hoped, prevent the outbreaks. The farming operations are Norwegian owned, as they are in British Columbia, by Marine Harvest or Cermaq. The companies contend the Chilean government caused the farm collapse by relaxing its farming regulations to boost fish-farm profits, but the net-pen critics point out that the profits go to Norway, and the salmon eggs used in the Norwegian-owned farms in Chile came from Norway and certainly caused the ISA contagion. The Norwegian corporations also own 97% of British Columbia fish farms, and have used the same Norwegian Atlantic salmon eggs, according to the "Farmed Salmon Exposed" DVD, produced by

*For more information on the impacts of salmon farming go also to the Coastal Alliance for Aquaculture (

Bay of Fundy Salmon Paradise Lost (ASF Bay of Fundy map here)

*The most severe regional impacts on wild Atlantic salmon caused by farm-raised salmon operations have been documented by the Atlantic Salmon Federation (See The largest decline of wild Atlantic salmon in North America occurred in the Bay of Fundy over the past 40 years, coincident with the opening of net-pen fish farms there. The decline was documented at an ASF October, 2012 closed-containment workshop, held at the Wilfred M. Carter Atlantic Salmon Interpretive Center in Chamcook, New Brunswick, Canada.

When, in the early '80s, I fished the small Cape Breton Bay of Fundy and Northumberland Strait salmon rivers (the Stewiack, and others) with Lee and Joan Wulff, and Poul Jorgensen, fall runs of wild salmon were already small (from 300 to 400 fish). The Stewiak runs in the '70s numbered 1500 fish or more, but by 2000 the Stewiack had few if any salmon returns and the mainland Magaguadavic in southwest New Brunswick, a river that had averaged 800 returning wild salmon each year, by 1992 had dropped to 293 and then to 19 by 2011. The river is located at the center of the Bay of Fundy open-net-pen aquaculture sites. It now has more net-pen escapee salmon returning each year than wild fish.

*By 1990, 52 west-coast Nova Scotia rivers from the Bay of Fundy to Halifax were closed to salmon sport fishing, and they have not been reopened for lack of returning wild salmon. During the same period all east-coast salmon rivers were also closed to fishing. (In the '80s, the southwest coast streams were closed for lack of salmon due to severe acidification, most of it caused by sulfurous and nitrous oxides emitted by upper Midwest coal-fired electrical plants and transported airborne to the region.) The famous St. Mary's River (with a fish farm in its estuary) was also more recently closed to fishing. None of the West Coast streams have been reopened and there are no signs of an upturn in returning salmon. The West River at Antigonish and the famous Margaree River (both out of the Bay of Fundy fish-farm/wild-salmon pathways) still have healthy returns of wild salmon.

The Department of Fisheries and Oceans (DFO) scientists contend that that Bay of Fundy salmon declines, while partially due to net-pen salmon farming, may also be due to a variety of other factors, including a rapidly expanding shark population there, habitat declines in the rivers, ocean-netting interceptions of salmon, and North Atlantic temperature declines that can cause declines in sea-pasture productivity. A long decline of British Columbia Fraser River sockeye salmon runs (at 10 million fish, historically the largest runs in Canada) occurred during the same period coincident with rising river temperatures due to global warming, and coincident with the establishment of salmon farms near the river mouth and the Georgia Strait. (Graph of Fraser River sockeye decline here and map of Fraser River smolt migration route fish farms in the Georgia Strait)

Larry Shortt, a Nova Scotia Salmon Association director, says most of the salmon decline in Nova Scotia is due to the establishment of fish farms in the Bay of Fundy and elsewhere, but he points out that the arrival of large numbers of restored striped bass traveling from U.S. waters to Nova Scotia tributaries to feed in the '80s may have had an impact on the southwest-coast wild salmon, as did habitat destruction in the Halifax-area rivers due to home construction.

The Salmon Association's habitat restoration projects have dramatically improved salmon returns on some rivers such as the West River in Sheet Harbor (using Norwegion-style limestone dosing at a cost of $50K per year), which has raised the river's ph. from 4.3 to 5.5 and caused smolt counts to jump from 3,000 to 33,000.

Shortt says that most salmon rivers in Nova Scotia are in dire need of wild salmon. He also warns that in 2014 the Greenland intercept ocean netting will reopen and 78 metric tons of Atlantic salmon will be taken (after two decades of closure under buy-outs, arranged in 2002 by Iceland's salmon conservationist Orri Vigfusson and his Atlantic Salmon Fund, the ASF, and NASCO under the Greenland Agreement.) Seventy five percent of those salmon are of northeast coast of North American rivers origin. The agreement saved an estimated 30,000 wild salmon from the nets and stabilized the eastern-Canada populations in their '70s-'90s decline, albeit at historic lows. Subsistence fishing in Greenland and eastern Canada takes an estimated 60,000 salmon annually.

Editor's note. Nova Scotia angler salmon sport-fishing days between 1988 and 2005 dropped from 109,511 to 20,819 as the salmon disappeared and angler numbers participating dropped from 7,497 to 2,598.

The ASF Takes On DFO

The Atlantic Salmon Federation ( reports that a 2008 Dalhousie University global study by Jennifer Ford and Ransom Meyers shows that worldwide there is a much steeper decline (as much as 50 percent) in wild salmon living in rivers adjacent to salmon farming than in wild-salmon rivers far from salmon-farming operations. Similar declines have been reported on wild-salmon rivers in Norway, Ireland, and Scotland. Norway forbids the establishment of fish farms on ocean pathways of wild-salmon smolts as they leave their rivers of birth and head for ocean pastures. (Norwegian scientists say attacks from sea-lice in heavily infested floating fish farms can attack and kill many of the wild salmon smolts as they pass by and thus doom returns of adult salmon to spawn in their natal rivers.)

Outcries by nongovernmental scientists and wild-salmon advocates in eastern Canada and British Columbia have called for an end to open-net-pen fish farming to protect remaining stocks of wild salmon, but the governments, which support and promote net-pen aquaculture both financially and bureaucratically, have turned deaf ears. The salmon conservationists point out that DFO has a mission conflict of interest: Its mission is to preserve wild salmon, but it supports (scientifically, financially, and politically) ocean-estuary net-pen farming.

*Net-pen escaped salmon (caused by storms, accidents, equipment failures and vandalism) have until recently not been reported by the industry, but in 2010 184,000 farmed fish that escaped in three events were finally reported by the Bay of Fundy industry and farmed fish showed up in the St. Johns and Magaguadavic rivers.

*ASF scientific studies on the Magaguadavic revealed successful spawning of farmed fish inter-breeding with wild stocks, and genetic survival-fitness reductions in wild stocks due to the inter-breeding of farmed fish with wild fish.

*In 2012 infectious salmon anemia (ISA) outbreaks hit aquaculture operations in Nova Scotia and then Newfoundland, totaling at least 1 million farmed salmon. In the entire Bay of Fundy during the 1996 to 2012 period 10 million ISA-infected fish were slaughtered. Compensation paid by Canadian federal and provincial governments for the destroyed farmed salmon to the industry totaled more than $100 million. This strong national and provincial financial and regulatory support of salmon fish farming has expedited the commercial growth of the industry from Norway to Ireland, Canada, America, and Chile. And, as ocean-based-aquaculture critics point out, the strong national promotions of fish farming is based on government concerns for raising low household incomes in rural sea-coast areas where fish are farmed, as well as marginally raising national GDPs.

*ISA outbreaks in Maine farmed-fish operations from 2001 through 2003 saw 2.5 million fish destroyed and farming operators received $5.8 million in compensation for the fish losses and another $2.5 million from the USDA for site clean-up.

ISA was first discovered in North American wild salmon by the Atlantic Salmon Federation in the Magaguadavic River by Federation researchers in 1999. The Federation has called for the following measures to prevent the further decline in wild-salmon populations in the Bay of Fundy.

1. A moratorium on the use of transgenic salmonids [various nonnative genetic strains of Atlantic salmon], until such time as a full evaluation of potential impacts of escaped transgenics has been conducted and appropriate safeguards developed before they are used in the industry. [Editor's note. Aquaculture researchers in eastern Canada are trying to create a special genetic strain of Atlantic salmon for the net-pen use that, they hope, might solve some of the industry's current problems with existing net-pen salmon genetics. The ASF objects to this approach, pointing out that escapee salmon could still doom wild runs of fish by interbreeding with the wild fish and by spreading infections to them.]

2. No extension of salmon farming within the Bay of Fundy Zones I and II beyond existing areas of farming pending identification of solutions to the risks to wild salmon posed by the farming.

3. Expanded research into methods to attain environmentally sustainable aquaculture.

4. Continued development of equipment and procedures to eliminate fish diseases and epidemics in the aquaculture industry.

5. All aquaculture salmonids should be identifiable through tagging, genetic characteristic, or other methods to the point of origin.

Over the past decade, the ASF actively sought the cooperation of the fish-farming industry and the Department of Fisheries and Oceans in the search for answers to the severe decline in Atlantic salmon in the Bay of Fundy and its obvious causal connection to net-pen fish farming. And while marginally cooperating with the call for transgenic controls in fish-farming, the industry holds the trump cards with the DFO and provincial governments on what actually happens in ocean net-pen farming. And they show little inclination to move their net pens out of the sea and onto land, while they quietly explore the promise of closed-containment aquaculture.

British Columbia and the Decline of Fraser River Sockeye

In October, 2012 the Cohen Commission released its three-year, $26 million, 1000-page, scientifically conducted, nonpolitical report titled "The Uncertain Future of the Fraser River Sockeye," (google: cohencommmissionfinalreport). The commission was chaired by the Hon. Bruce T. Cohen, who authored the report and concluded: "The potential for harm posed to Fraser River sockeye salmon from salmon farms is serious or irreversible. Disease transfer occurs between wild and farmed fish, and I am satisfied that salmon farms along the sockeye migration route have the potential to introduce exotic diseases and to exacerbate endemic diseases that could have a negative impact on Fraser River salmon."

He further concluded that: "I accept the undisputed evidence that Fraser River sockeye face some likelihood of harm occurring from diseases and pathogens on fish farms. However, I cannot quantify the likelihood of harm based on the evidence before me. The likelihood of this [fish-farms causing disease in wild fish] outcome occurring and resulting requires more study."

Commenting on his commission findings after the report was published, Cohen said the 2-degree C. rise in the lower Fraser River over the past 60 years is the "elephant in the room" of sockeye decline," despite all the other environmental factors reported.

Similar 2-degree C. rises in river summer temperatures have been reported across the entire Pacific Northwest during the same period, all attributed to global warming. And as the Cohen Report says, "both in Canada and the U.S. 64 sockeye populations from Washington State, British Columbia, and Alaska show a decrease in productivity, especially in the past decade and often also over a period of decline starting in the late 1980s or early 1990s."

The Cohen commission created the most thorough and exhaustive, science-based fish-species study of its kind on a single river watershed in Canadian history. It included fact-based studies from all freshwater/saltwater life-sciences, conducted over decades by DFO scientists. Cohen recommended "a freeze on all net-pen salmon-farm production in the Discovery Islands [a narrow channel taken by migrating Fraser River sockeye smolts on their way to ocean pastures] until Sept. 30, 2020. "If by that date DFO cannot confidently say the risk of serious harm to wild stocks is minimal, it should then prohibit all net-pen farms from operating in the Discovery Islands [where there is a concentration of net-pen farms]. And if before Sept 30, 2020 the government determines that salmon farms pose more than minimal risk to Fraser River sockeye, the government [should] prohibit their operation immediately"

Unfortunately the commission's 75 concluding, science-based recommendations to save the sockeye runs were undercut by the Canadian government preempting it with fundamental, damaging—and evidently political--changes to the governing federal Fisheries Act before the report could be completed and published.

Commenting on the federal preemption, Gwen Barlee, policy director with the Wilderness Committee said that government changes to the Fisheries Act "gutted key tools [in the Commission recommendations] that protect wild salmon in BC." Judge Cohen in his report commented: "Failure to cost out and put someone in charge of implementing the 2005 Wild salmon Policy (WSP) is gravely disappointing. The DFO simply does not have the funds to do the job." For lack of funding, in effect Canada's Wild Salmon Act has never been enforced by DFO.

Chief Bob Chamberlin of a First Nations tribe located in the Broughton Archipelago (he describes it as "ground zero of the fish-farm struggle") said: "The 75 Cohen Commission recommendations are something our nation has been advancing to have addressed for decades, but the commission's recommendations have fallen on deaf government ears."

Included in the wide-ranging and inclusive Commission report as partial reasons (studied) for the Fraser River sockeye run are a host of contributing "stressors", including: climate change, infectious disease, contaminants, pre-spawn mortality, marine conditions, pathogens, human activities including development, logging, agriculture, gravel removal, pulp-and-paper mills, metal mining, municipal wastewater, predators, and aquaculture. Cohen emphasizes that no stressor has been proved a "smoking gun," but river warming is a prime suspect.

The Cohen Commission concluded its report with 75 recommendations to address the man-made and environmental factors ("stressors") it found as contributors to the long-term decline of wild Fraser River sockeye salmon.

The Genomic Threat to Salmon

Of impressive importance in the report were the reported observations of DFO molecular geneticist Dr. Kristina Miller who concluded from her studies on Fraser River sockeye that: "In all three tagging studies the same genomic signature was associated with poor spawning success, whether the fish were tagged in a marine environment, in the lower river, or on the spawning grounds. In the marine environment when the fish carried this mortality-related signature, they had a 13.5 times lower probability of spawning. A similar pattern was found on tagged lower-river sockeye and spawning-ground-tagged sockeye.

With this signature pattern, Miller found an association with more rapid entry of returning adult sockeye into the river and a faster migration to the spawning grounds. In 2006, 50% of returning sockeye carried this mortality-related signature. Miller: "The study shows unequivocally that Fraser River sockeye are entering the river in a compromised state, that survivorship was somewhat predictable based on gene expression [greater than] 200km before salmon reached the river, that stocks may be affected differently, and that the freshwater environment alone may not be the sole source of the highly fluctuating mortalities of salmon in the river.

"In 2008, 60 percent of smolts left the river with the same unhealthy signatures in the brain, 40% in the liver. Overall 82% of the fish were affected in at least one tissue. There was a 30% reduction in brain prevalence of the signature from summer to fall in the ocean and a 50% reduction in the liver. Overall, there were 2.4 times as many fish with the signature in the fall as in the summer. If these decreases in prevalence were due to mortality, and if we assume that 120 million smolts left the river in 2008 (there may have been more), we could account for the loss of [more than] 27 million salmon in 2008 associated with the unhealthy signature alone."

Miller also noted that a parvovirus (Parvicapsula minibicornis) parasite in outmigrating Fraser River smolts, targets the fish's kidneys (adults as well) and affects the fish's swimming ability. She says the pre-spawn mortality-risk genomic profile is reported by scientists elsewhere to be closely related to the parvo virus, which flourishes in the net-pen farms.

[Editor's note. Science has documented that Fraser River sockeye have been dying before spawning since the 1940s, the cause closely tied to high river temperatures. In 2009 the Fraser River returning-sockeye runs suffered their largest collapse in modern recorded history, perhaps due in large part to the previous year smolt and adult mortalities caused by the deadly gene signature linked to the parvovirus, which the DFO says is widely prevalent in the net-pen farms. The 2010 returns of sockeye to the Fraser were near-record in numbers. Net-pen farming began in BC in the 1980s and '90s]

Salmon Diseases and Pathogens

What is ISA (Sidebar) (for online use)

ISA is a virus similar to influenza that in its virulent form can kill crowded salmon quickly, so where ISA is detected in net-pen farms the fish in most infected pens are quickly destroyed. The organism may be endemic--though quiescent in its nonvirulent form--in Scandinavian wild salmon. It was not discovered there in fish farms until 1984--when it first became known to science--and in wild salmon in 1999. Some scientists believe the nonvirulent form of the virus changed genetically in the crowded fish farms to the virulent form. The scientists say it arrived in North America in Norwegian fish-farm salmon eggs used to establish net-pen farming operations in eastern Canada, British Columbia, and Chile. It thrives in cold water and infects fish through the gills. When fish are slaughtered, the virus is shed through urine, feces, epidermal mucus, gonadal fluids, blood, and tissue wastes. It can be transmitted either through water, usually by close contact between fish, and sea lice may act as mechanical vectors.

Of the two known forms of ISA, the virulent one which kills fish and the nonvirulent one which does not, U.S. Scientists in the Puget Sound area, after completing a two-year research to determine if the virulent form of ISA has been found in wild or hatchery-raised Pacific salmon, recently reported that there has been no ISA found in wild salmon, hatcheries, or fish farms in the U.S. Northwest, or in British Columbia.

To date the virulent form of ISA presence in BC farmed and wild salmon has only been reported by several scientists, Alexandra Morton, Ph.D., a nongovernmental scientist based in northern Vancouver Island, British Columbia, and by Dr. Kristina Miller, head of the Molecular Genetics Section, Salmon and Freshwater Ecosystems Div. for the DFO in British Columbia.

Morton found dead pre-spawn adult sockeye on the Fraser River in BC, and tests by an accredited, non-DFO lab found them positive for ISA. But the DFO did its own tests on the same fish tissue (frozen for several months) and said there was no ISA found, just "false positives". (To detect ISA using a scientifically-valid technique, analysts say they must test fresh flesh from recently killed fish.)

Morton says "There are strains of ISA that no one has ever been able to culture [from freshly killed salmon tissue and the strains grown in the lab], so the government's findings [on nonfresh fish] do not mean that ISA is not here in our wild fish. Farms take up relatively small space in the sockeye migration channel, but a single viral outbreak in one net-pen farm near the Campbell River can produce 65 billion infectious viral particles released to the channel per hour. They can fill that entire Fraser River sockeye-smolt migration route [The Georgia Strait].

"I am limited [by the government] to sampling dead fish from the supermarket—iced for a matter of days. Thus the tissue samples taken from those fish and sent to nongovernmental labs have never revealed a complete, intact, ISA viral sequence. But the viral pieces from the lab do match known ISA sequences of European origin. The ISA virus is here in our wild salmon. We need testing of both live wild salmon and net-pen salmon done by officially recognized, nongovernmental labs."

The Threat: Immuno-Suppressive Diseases

The BC DFO says no virulent form of ISA has been found in farmed fish by its scientists (although Dr. Miller says it may be there). It has banned Morton from testing all net-pen salmon operations, forbade Miller from discussing her findings with the media, forbade Miller from testing farmed salmon for salmon leukemia (SLV), though DFO reported that the leukemia is common in all salmon feedlots along the sockeye Georgia Strait migration route. Its Plasmacytoid (PL) form is infectious and has caused mortality in pen-raised king salmon since 1988. The leukemias are similar to other immuno-suppressive diseases common to flow-through net-pen salmon farms. Scientists say they are present at low levels in wild fish, but intensive aquaculture (tightly packedfish)can supercharge the diseases and cause rapid genetic mutations to new immuno-suppressive forms yet unknown to science.

The DFO Canadian Food Inspection Agency (CFIA) test lab punished Fred Kibenge Ph.D., prof. of virology at the Atlantic Veterinary College at the U. of Prince Edward Island (the scientist who tested Alexandra Morton's sockeye found in the Fraser River and confirmed the presence of ISA) by requesting that the Office of International Epizootics (OIE) of the World Health Organization withdraw his lab's certification as the WHO's sole disease-reference lab in the Western Hemisphere for testing fish diseases. The OIE complied but never explained why.

Commenting on the government's effort to choke off scientific discussion of ISA research, Prof. Andrew Weaver, an environmental scientist at the University of Northern Victoria, BC, says, "You can't have informed discussions if the science isn't allowed to be communicated. The public-relations message number one is that you have to set the conversation. You don't want to have a conversation on someone else's terms. And this is being applied to science in discussions about oil sands, climate change, and salmon in British Columbia." [by the government in power]

A CFIA representative testified to the Cohen Commission that if Kibenge's ISA findings had been confirmed by the OIE, it could have resulted in Canadian exports of farmed Atlantic salmon being banned for world trade, a strong economic blow to Canada, and especially British Columbia and the Maritime provinces.

Also testifying before the Cohen Commission, Dr. Miller said that while ISA may have infected some farmed salmon in British Columbia, and ISA could be a factor in the Fraser River sockeye decline, she agrees with other scientists that there is no single major factor in the Fraser decline.

ISA is believed to be highly adaptive genetically, and scientists are watching closely to see if the contagious virus will mutate to a more virulent and contagious form that can quickly threaten or destroy both net-pen and wild-salmon populations. Symptoms of ISA in fkish include: Infected salmon become lethargic, with lifted scales, protruding eyeballs, skin lesions, pale gills, and internal hemorrhages. The virus is not a threat to humans. (End sidebar)

As the reported problems with Atlantic salmon net-pen fish farming multiplied, Alaska in defense preemptively banned the establishment of such farms in it waters. Commercial fishing for wild and hatchery-bred Pacific salmon is occupationally the state's largest industry.

Sea Lice (sidebar to be used online with Diseases and Pathogens)

Sea Lice are tiny crustaceans that prey on fish, proliferate in crowded saltwater fish farms, and spread to wild fish. They have decimated wild seatrout and salmon populations near fish farms in Ireland, Scotland, and Norway and as few as 10 sea lice can kill an Atlantic salmon smolt traveling from its home river to sea. The explosion of sea lice in densely crowded fish farms requires treatment with strong chemicals, and they have become resistant to Slice, the chemical of choice by the farms (which intend to use more effective chemicals for control, but which the ASF says may impact crustaceans such as forage-base krill, an important food used by other important saltwater fish.

PRV or HSMI: The Greatest Threat

PRV (piscine reovirus), otherwise known to scientists as HSMI (heart and skeletal muscle inflammation), is a highly infectious piscine virus discovered in Norwegian net-pen farms in 1999 and since found in United Kingdom net-pen farms. According to Dr. Alexandra Morton, the virus is "spreading like wildfire" in BC fish farms. She considers it to be "the greatest threat to wild salmon in British Columbia, "more dangerous than ISA".

The PRV symptoms include physical stunting, weak muscles, trouble swimming, or pumping blood; and it's usually fatal. She notes that even traces of PRV can short-circuit genomic signals in the fish's ability to navigate, swim, and reproduce. Morton has personally filed a lawsuit against the Ministry of Fisheries and Marine Harvest to prevent the use of Atlantic salmon infected with PRV in fish farms located along the Georgia Strait travel route of Fraser River sockeye.

Bacterial Kidney Disease (BKD) is of high risk to sockeye and other salmon species, causing chronic systemic disease and high mortality rates in both fresh and salt water in both young and adult fish.

IHN, (infectious hemostasis necrosis) causes acute systemic disease and mortality in juvenile salmon (in 1989 it caused 56% mortality in Weaver Creek, BC fry). It is less virulent in older fish and in salt water.

PD (pancreas disease) is the number one cause of death in net-pen salmon. It is not considered a threat to wild salmon by the DFO.

The salmon diseases described above have two things in common: They are not threatening to humans. They are all biological "stessors", considered by the scientific community as possibly contributing, at one level or another--or in combination--to the immuno-system compromises that can cause immediate and longterm declines in salmon populations. Unexpected genetic changes in these organisms, caused by high-density aquaculture, can greatly increase the complexity of scientific research in searches for a "smoking gun" in salmon population declines.

Morton Warns of BC Salmon Decline

Dr. Alexandra Morton has done foundational work examining the injurious effects of sea lice on wild sockeye smolts swimming by fish farms near her home in British Columbia. As a result of her findings, she has become an outspoken critic of the threats that the fish farms are posing to wild salmon stocks, the ecological damage done to the sea floor under the farms, and the lack of concern shown by governmental (DFO) scientists who say they cannot confirm her work with their own research, although many scientific papers published in Norway and other Atlantic-salmon countries have reached conclusions that are similar to Morton's findings in British Columbia.

Dr. Morton made her name in science with her research on Killer Whales (Orca), but she may be remembered as a savior of British Columbia wild Pacific salmon if her current research gains enough public support to halt the Canadian and British Columbia DFO in their headlong promotion and protections of ocean net-pen farming.

Morton, her river wild-salmon research technicians, and some native First Nation fishermen, warn that many BC salmon-spawning streams are losing, or have lost, up to 50 percent of their wild pre-spawn sockeye and the critical spawning regeneration they represent. Film footage taken on spawning streams by the Morton team shows many dead pre-spawn sockeye, with red blisters, lesions, bloody guts, and heart blisters—telltale signs of ISA infection. (See

Government documentation of the riverine pre-spawn sockeye declines does not exist because the DFO has not mounted widespread (with the exception of the Fraser River) spawning-season in-river research to determine what is happening. Net-pen critics say this is symptomatic of the DFO's "See no evil; hear no evil" attitude in its attempts to prevent the bad news about ISA from reaching the media, which, if reported, could collapse the world markets for British Columbia farmed salmon.

Morton points to the long-term Fraser River spawning-run decline (chart of decline here) as proof of what can happen when many net-pen fish farms are located along a travel route (the Georgia Strait) (photos of Georgia Strait net-pens farms here) for sockeye smolts--young-of-the-year salmon headed to the sea from their natal rivers. They pass, or linger near, the net pens, where they pick up sea lice (in Norway as many as 200 sea lice were found on one wild salmon--as few as four can kill a wild salmon smolt); the deadly salmon alpha virus, ISA, or PRV, which has been found in all BC farmed salmon by DFO. (It says the virus does not hurt them.)

Dr. Morton and Dr. Kristi Miller warn that wild fish may be more susceptible to molecular effects than farmed fish are, changes that can affect their genomic survival capabilities. They say there is much yet to be learned in fish science about the possible interaction of farm chemicals on both wild and farmed salmon. Miller points out that a small change in a salmon's genetic signals can destroy its ability to function and survive.

The Morton research has been consistently, and repeatedly, thwarted by the BC DFO. Banned from taking fish samples at the BC farms, she has gone to area grocery stores and purchased BC-farmed salmon and had them tested in Norway for ISA (DFO won't allow her to use their testing facilities). The store Atlantic salmon are often thin, emaciated, and with deformed heads, a sign of ISA infection that has caused the fish to stop feeding and starve. She says some farms obviously do not destroy some diseased fish but send them to be consumed by the public in the belief that naive customers won't know the difference between a healthy and a diseased fish.

In response to her efforts, the BC DFO proposed a Bill 37 in the BC legislature that would, if passed, make it a criminal offense ($75K fine and two years in jail) to buy grocery-store farmed salmon and test them for diseases. Apparently embarrassed by public response to this effort, DFO withdrew the bill.

Morton says she has given up on changing the behavior of the BC DFO, but she has not given up hope that the BC and Canadian public will rise up and vote into office representatives who will make the national DFO obey its charter mission: to protect wild BC salmon. Her mantra is "Buy wild fish and eat cooked fish. And don't ever eat raw fish. . . of any kind." Surveys show that up to 80% of BC voters want ocean-based net-pen farms to be moved eventually onshore to closed-containment farming facilities.

Let's Move the Net Pens Onshore By 2020

The Cohen Commission did Canada a significant public service in proving scientifically that there are many multi-faceted environmental "stressors" that have contributed to the longterm decline of Fraser River sockeye. But it did not take the final step. . .of accusing the British Columbia and national DFO of actively supporting and promoting the net-pen agriculture that threatens the future of wild sockeye and other Pacific salmon, the iconic natural resource that belongs to the people of Canada.

The Bay of Fundy 30-year decline of wild-salmon, primarily caused by net-pen farming of Atlantic salmon, should have been mentioned prominently as an alarm bell in the Cohen report, no doubt because there was no DFO science to prove the connection. However, Chile's proven net-pen ISA disaster should have been a marquee warning.

Judge Cohen rightly contends that there is just not enough confirmed scientific proof of the net-pen threat to Fraser River sockeye salmon. From a strictly legal standpoint, he is correct. But he made clear his moral and ethical beliefs when he called for the closure of the BC net-pen farms by Sept. 31, 2020 if his required science-based tests do not prove that they are no threat to wild salmon in the province. In other words, the scientific tests must prove a peer-reviewed conclusive negative: that open net-pen aquaculture is no threat to wild salmon in the province. If it happens, the net pens will be closed or forced onto shore.

More disturbing is the role of the Canadian government in its attempts to throttle or hide nongovernmental, peer-reviewed scientific studies that prove net-pen, flow-through aquaculture creates man-made, supercharged brews of diseases and pathogens, creating genomic stressors that, collectively, are killing or genomically damaging wild BC And Bay of Fundy salmon.

This environmental train wreck was understandably unexpected early in the net-pen game by naïve governmental agencies and political leaders, who sought to promote and protect the seemingly benign growth of an ocean industry that would create badly needed jobs in the wild and beautiful, salmon-rich margins of ocean Canada. But times have changed and the unhappy facts are in.

There are indications that DFO Canada hoped to kill the infant Cohen Commission report before it saw the light of day. Fortunately the Canadian media has done a sterling job in keeping the Commission findings, and the calls for action by the Atlantic Salmon Federation, alive. Otherwise, the Commission's calls for reform will gather dust on DFO shelves, as did the Wild Salmon Policy Act, in both cases for lack of leadership and the funding to right the wrongs created by net-pen farming and other man-made threats to wild salmon.

All Atlantic- and Pacific-salmon conservationists once held great hope for the future of flow-through net-pen aquaculture: We thought it would be the savior of our salmon, the wild children of our rivers and North America's natural and spiritual heartbeat. But, as Atlantic Salmon Federation President Bill Taylor says in the opening quote of this article, the worldwide peer-reviewed, uncontested, science is in place to prove that flow-through net-pen aquaculture must be moved onshore into proven closed-containment facilities. Otherwise we will lose our North American wild salmon. Tell this to the people, who already know the truth, and to the political leaders in Ottawa, who do not.

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