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Speynut 12-10-2002 10:00 AM

Salmon Aquaculture Impact
Here's a very interesting 12/20/02, LA Times article on the environmental concerns over salmon farming. John

Fish Farms Become Feedlots of the Sea
Like cattle pens, the salmon operations bring product to market cheaply. But harm to ocean life and possibly human health has experts worried. By Kenneth R. Weiss, Times Staff Writer
PORT McNEILL, Canada -- PORT McNEILL, Canada -- If you bought a salmon filet in the supermarket recently or ordered one in a restaurant, chances are it was born in a plastic tray here, or a place just like it.

Instead of streaking through the ocean or leaping up rocky streams, it spent three years like a marine couch potato, circling lazily in pens, fattening up on pellets of salmon chow.

It was vaccinated as a small fry to survive the diseases that race through these oceanic feedlots, acres of net-covered pens tethered offshore. It was likely dosed with antibiotics to ward off infection or fed pesticides to shed a beard of bloodsucking sea lice.

For that rich, pink hue, the fish was given a steady diet of synthetic pigment. Without it, the flesh of these caged salmon would be an unappetizing, pale gray.

While many chefs and seafood lovers snub the feedlot variety as inferior to wild salmon, fish farming is booming. What was once a seasonal delicacy now is sometimes as cheap as chicken and available year-round. Now, the hidden costs of mass-producing these once-wild fish are coming into focus.

Begun in Norway in the late 1960s, salmon farming has spread rapidly to cold-water inlets around the globe. Ninety-one salmon farms now operate in British Columbian waters. The number is expected to reach 200 or more in the next decade.

Industrial fish farming raises many of the same concerns about chemicals and pollutants that are associated with feedlot cattle and factory chicken farms. So far, however, government scientists worry less about the effects of antibiotics, pesticides and artificial dyes on human health than they do about damage to the marine environment.

"They're like floating pig farms," said Daniel Pauly, professor of fisheries at the University of British Columbia in Vancouver. "They consume a tremendous amount of highly concentrated protein pellets and they make a terrific mess."

Fish wastes and uneaten feed smother the sea floor beneath these farms, generating bacteria that consume oxygen vital to shellfish and other bottom-dwelling sea creatures.

Disease and parasites, which would normally exist in relatively low levels in fish scattered around the oceans, can run rampant in densely packed fish farms.

Pesticides fed to the fish and toxic copper sulfate used to keep nets free of algae are building up in sea-floor sediments. Antibiotics have created resistant strains of disease that infect both wild and domesticated fish.

Clouds of sea lice, incubated by captive fish on farms, swarm wild salmon as they swim past on their migration to the ocean.

Of all the concerns, the biggest turns out to be a problem fish farms were supposed to help alleviate: the depletion of marine life from overfishing.

These fish farms contribute to the problem because the captive salmon must be fed. Salmon are carnivores and, unlike vegetarian catfish that are fed grain on farms, they need to eat fish to bulk up fast and remain healthy.

It takes about 2.4 pounds of wild fish to produce one pound of farmed salmon, according to Rosamond L. Naylor, an agricultural economist at Stanford's Center for Environmental Science and Policy.

That means grinding up a lot of sardines, anchovies, mackerel, herring and other fish to produce the oil and meal compressed into pellets of salmon chow.

"We are not taking strain off wild fisheries. We are adding to it," Naylor said. "This cannot be sustained forever."

In British Columbia, the industry, under pressure from environmentalists, marine scientists and local newspapers, is taking steps to mitigate some of the ecological problems.

"We have made some mistakes in the past and we acknowledge them," said Mary Ellen Walling, executive director of the British Columbia Salmon Farmers Assn. "We feel the industry is sustainable, if well-managed, and we have a code of practices that is followed by all of our member companies."

Nearly 30 farms are preparing to move to less ecologically fragile areas, under orders from Canadian authorities.

Some farms have installed underwater video cameras to detect when fish quit feeding, so workers can stop scattering food pellets. Many farms are switching to sturdier nets to stop fish from escaping and keep out marauding sea lions, which are shot if they penetrate the perimeter.

The industry now recognizes that it will soon be pushing the limits of the ocean.

"There will come a time when our industry will use more of the fish oil and fish meal than is available," said Odd Grydeland, an executive at Heritage Salmon in British Columbia. "Our biggest challenge is to find substitute grains for fish meal and fish oil."

Farm-raised salmon now dominates West Coast markets, arriving daily from Canada and Chile. About 80% of the salmon grown in British Columbia goes to markets from Seattle to Los Angeles.

The salmon industry took off so fast in British Columbia in the 1980s that the provincial government, worried about the environmental toll, imposed a ban in 1995 on any new farms.

The industry responded by stuffing, on average, twice as many fish into each farm. Today, farms typically put 50,000 to 90,000 fish in a pen 100 feet by 100 feet. A single farm can grow 400,000 fish. Others raise a million or more.

The moratorium on new farms was lifted in September by the provincial government after voters elected a pro-business slate of lawmakers and administrators. As a result, 10 to 15 farms are expected to open each year over the next decade.

Five international companies -- three of them based in Norway -- control most of the existing farms. Nearly all are situated around Vancouver Island, which begins outside Seattle's Puget Sound and extends up the coast for 300 miles.

It's a lightly populated place of stunning beauty. Cedar, hemlock and Douglas fir grow right down to the high-water mark.

Massive tides flush rich blue-green waters through the archipelago of islands, straits, bays and inlets, nurturing five types of wild salmon. These, in turn, attract seals, sea lions, white-sided dolphins and the world's best known pods of killer whales.

Residents rely on boats and seaplanes to reach surrounding islands that host many of the farms. Each farm is a cluster of pens, often interconnected by metal walkways and tethered offshore by a lattice of steel cables, floats and weights.

In the midst of this idyllic setting, signs of strain on the marine environment are bubbling to the surface much the way diseases and parasites, incubated in European salmon farms, fouled the fiords of Norway and the lochs of Scotland.

In Norway, parasites have so devastated wild fish that the government poisoned all aquatic life in dozens of rivers and streams in an effort to re-boot the ecological system.

"The Norwegian companies are transferring the same operations here that have been used in Europe," said Pauly, the fisheries professor. "So we can infer that every mistake that has been done in Norway and Scotland will be replicated here."

Dale Blackburn, vice president of West Coast operations for Norwegian-based Stolt Sea Farm, said his staff works very closely with its counterparts in Norway. But, he said, "It's ridiculous to think we don't learn from our mistakes and transfer technology blindly."

Still, more than a dozen farms in British Columbia have been stricken by infectious hematopoietic necrosis, a virus that attacks the kidneys and spleen of fish.

Jeanine Siemens, manager of a Stolt farm, said, "It was really hard for me and the crew" to oversee the killing of 900,000 young salmon last August because of a viral outbreak.

"We had a boat pumping dead fish every day," she said. "It took a couple of weeks. But it was the best decision. You are at risk of infecting other farms."

Farms are typically required to bury the dead in landfills to protect wild marine life and the environment. But Grieg Seafood recently got an emergency permit from the Canadian government to dump in the Pacific 900 tons of salmon killed by a toxic algae bloom. The emergency? The weight of the dead fish threatened to sink the entire farm.

About 1 million live Atlantic salmon -- favored by farmers because they grow fast and can be packed in tight quarters -- have escaped through holes in nets and storm-wrecked farms in the Pacific Northwest.

Biologists fear these invaders will out-compete Pacific salmon and trout for food and territory, hastening the demise of the native fish. An Atlantic salmon takeover could knock nature's balance out of whack and turn a healthy, diverse marine habitat into one dominated by a single invasive species.

Preserving diversity is essential, biologists say, because multiple species of salmon have a better chance of surviving than just one.

John Volpe, a fisheries ecologist at the University of Alberta, has been swimming rivers with snorkel and mask to document the spread of Atlantic salmon and their offspring.

"In the majority of rivers, I find Atlantic salmon," Volpe said. "We know they are out there; we just don't know how many, or what to do about them."

His research focuses on how Atlantic salmon can colonize, if given a chance. It has terrified the U.S. neighbors to the north. Alaskan officials banned fish farms in 1990 to protect their wild fishery. So they don't take kindly to British Columbian farms creeping toward their southern border.

Although native Pacific salmon are rare and endangered in the Lower 48, Alaska's salmon fisheries are so healthy they have earned the Marine Stewardship Council's eco-label as "sustainable." The council's labels are designed to guide consumers to species that are not being overharvested.

Recently, the prospect of genetically modified salmon that can grow six times faster than normal fish has heightened anxiety. Aqua Bounty Farms Inc., of Waltham, Mass., is seeking U.S. and Canadian approval to alter genes to produce a growth hormone that could shave a year off the usual 2 1/2 to three years it takes to raise a market-size fish.

Commercial fishermen and other critics fear that these "frankenfish" will escape and pose an even greater danger to native species than do the Atlantic salmon.

"Nobody can predict just what that means for our wild salmon," Alaska Gov. Tony Knowles said. "We do see it as a threat."

Canadian commercial fishermen, initially supportive of salmon farms, have grown increasingly hostile. They were stunned in August when their nets came up nearly empty during the first day of the wild pink salmon season in the Broughton Archipelago at the northeast end of Vancouver Island.

"There should have been millions of pinks, but there were fewer than anyone can remember," said Calvin Siider, a salmon gill-netter. "We can't prove that sea lice caused it. But common sense tells you something, if they are covered by sea lice as babies, and they don't come back as adults."

Alexandra Morton, an independent biologist and critic of salmon farms, began examining sea lice in 2001 when a fishermen brought her two baby pink salmon covered with them.

Collecting more than 700 baby pink salmon around farms, she found that 78% were covered with a fatal load of sea lice, which burrow into fish and feed on skin, mucous and blood. Juvenile salmon she netted farther from the farms were largely lice-free.

Bud Graham, British Columbia's assistant deputy minister of agriculture, food and fisheries, called this a "unique phenomenon."

"We have not seen that before. We really don't understand it," he said. "We've not had sea lice problems in our waters, compared to Scotland and Ireland."

Salmon farmers point out that the sea louse exists in the wild. Their captive fish are unlikely hosts, the farmers say, because at the first sign of an outbreak, they add the pesticide emamectin benzoate to the feed.

Under Canadian rules, farmers must halt the use of pesticides 25 days before harvest to make sure all residues are flushed from the fish. If that's done, officials said, pesticides should pose no danger to consumers.

European health officials have debated whether there is any human health risk from synthetic pigment added to the feed to give farmed salmon their pink hue.

In the wild, salmon absorb carotenoid from eating pink krill. On the farm, they get canthaxanthin manufactured by Hoffman-La Roche. The pharmaceutical company distributes its trademarked SalmoFan, similar to paint store swatches, so fish farmers can choose among various shades.

Europeans are suspicious of canthaxanthin, which was linked to retinal damage in people when taken as a sunless tanning pill. The British banned its use as a tanning agent, but it's still available in the United States.

As for its use in animal feed, the European Commission scientific committee on animal nutrition issued a warning about the pigment and urged the industry to find an alternative. But in response, the British Food Standards Agency took the position that normal consumption of salmon poses no health risk. No government has banned the pigment from animal feed.

Scientists in the United States are far more concerned about a pair of preliminary studies -- one in British Columbia and one in Great Britain -- that showed farmed salmon accumulate more cancer-causing PCBs and toxic dioxins than wild salmon.

Scientists in the U.S. are trying to determine the extent of the contamination in salmon and what levels are safe for human consumption.

The culprit appears to be the salmon feed, which contains higher concentrations of fish oil -- extracted from sardines, anchovies and other ground-up fish -- than wild salmon normally consume. Man-made contaminants, PCBs and dioxins make their way into the ocean and are absorbed by marine life.

The pollutants accumulate in fat that is distilled into the concentrated fish oil, which, in turn, is a prime ingredient of the salmon feed.

Farmed salmon are far fattier than their wild cousins, although they do not contain as much of the beneficial omega-3 fatty acids.

The industry complains that environmental activists have misinterpreted the contaminant studies, needlessly frightening consumers.

"The concern is that people will stop eating fish," said Walling, of the British Columbia Salmon Farmers Assn. "Salmon is a healthy food choice. Our Canadian government says this is a safe food."

Environmentalists in British Columbia and Scotland recently launched campaigns urging consumers to boycott farmed salmon until the industry changes many of its practices.

At the least, they want the farms to switch to solid-walled pens with catch basins to isolate farmed fish -- and their diseases, pests and waste -- from the environment. The ideal solution, they say, is to have the farmed stock raised in landlocked tanks.

Protests notwithstanding, the industry is expected to get a lot bigger. Demand for seafood is rising and will double by 2040, according to the U.N.'s Food and Agriculture Organization. Nearly half the world's wild fisheries are exhausted from overfishing, thus much of the supply will likely come from farmed seafood.

"Aquaculture is here to stay," said Rebecca Goldburg, a biologist who co-authored a report on the industry for the Pew Oceans Commission. "The challenge is to ensure that this young industry grows in a sustainable manner and does not cause serious ecological damage."


Bob Pauli 12-11-2002 11:23 PM

Speybum-Thanks for that posting
Salmon without Rivers

Reading this book makes you sick.

beau purvis 12-12-2002 10:12 AM

fish farms
last winter Ed Ward mentioned the thought that puget sound steelhead smolts migrate up th coast past those B.C. fish farms. one theory on the low returns for the "inside" rivers is the sea lice problem as they migrate out to sea. thanks for that very well done all inclusive piece on the problems. i used to be encouraged that we could stop chasing fish allover the seas and eliminate all the bycatch problems. now i am a firm believer in raising these fish where there are no resident wild populations.too much bad evidence from Norway. reminds me of how we were all seduced by fish ladders and hatcheries that suposedly would solve our problems.
Bob,i have not read that book yet.dont need that depression at present.however, i presently see our rivers as healthier than in times past.i see it as rivers without fish. lots of prime redd gravel without redds.the fish cant make it back.

OC 12-13-2002 09:08 AM

I think Ed Ward may have it right about Puget Sound Steelhead smolts migrating north up the coast and by all those wonderful Salmon farms. Last couple of years have been asking marine scientists if this could be so. Answer I get is not enough study done on smolt migration but what has been done shows that Puget Sound smolts go directly and quickley out the strait. That sounds fishy to me. How can we have 3 good years of ocean conditions with more than enough forage fish for food supply and not be getting our steelhead back?

Norway is not the only place where fish farms have killed off a large population of native fish. One of Ireland's coasts lost it's run of fish due to sea lice infestation from fish farms. On our east coast we had wild Alantic Salmon coming back quite well for years but have crashed in the last 5 years or so. Could that have anything to do with Maine and New Brunswick increasing their fish farming opportunities?

Fish farming should be an international crime and those very wealthy investors from Norway, Japan and the rest of the world should be brought to justice. They know exactly what fish farms are doing to the worlds oceans and its native peoples who have to live by these farms and can no longer feed their families due to the polution, removal of habitat and the disease of native fish. What do you want to bet that a lot of these investors no longer fish their home rivers in Norway because fishing sucks but spend many of fine day fishing Alantic Salmon now in Russia far away from the devistation their wealth and political power have created.

inland 12-13-2002 08:58 PM


With the history of salmon farms, and the destruction they are still causing, it seems logical that they are a contributing factor in this recent decline. Possibly more so than we know.

But, just to leave you in a good mood- Russia is not exempt from the problem. Fishing the Kola's E. Litza this past year, my partner landed a bright escapee of about 18#'s. Probably from the Norwegian farms.


OC 12-16-2002 08:48 AM

Thanks Inland,

I guess you can run but you can't hide for long. I wonder if they have a Salmon run in the rivers of N. Korea.

Gardener 12-18-2002 12:59 PM

The British Perspective
This issue is certainly a hot topic in UK circles, and one I feel very strongly about - apologies for not picking it up here earlier, but I don't normally look at this section. Apologies too for what will be a long post.

Perhaps the main issue currently is the question of sea lice and their effect on sea trout (sea-run browns), although there are other worrying consequences of this industry also.

Sea lice occur naturally in coastal waters, and attach themselves to salmon returning from their open-ocean feeding grounds. The concentration of salmon in an inshore farm leads to huge numbers of lice and their eggs. A few lice on an adult salmon aren't a problem. However, the lice also attack salmon and sea trout smolts after they decend the rivers to go to sea. These small fish are very vulnerable, and it is at this stage that the damage is caused. Smolts have been found, severely emaciated and infested in some cases with hundreds of lice which quite literally eat them away. It is sea trout in particular that are vulnerable because they feed in coastal waters and so the lice persist on them. By contrast, once salmon have 'run the gauntlet' they go to the open sea where lice are not a problem, although this is not to say that there is not significant mortality of salmon smolts as well as they pass through. Once famous sea trout fisheries like Loch Maree in Scotland and Delphi in Ireland have seen their numbers reduced to a fraction of their former catches. There appears to be a direct link between the placing of salmon cages near a river mouth and fall-off of sea trout numbers - and when cages are 'fallowed', numbers improve again. Fishermen have seen this correlation for years, although the fish farmers have only just acknowledged that a link exists at all.

Sea lice are controlled in salmon farms using chemicals such as 'Nuvan'. This is highly toxic to other marine life (as well as carcinogenic to humans), and has been linked to severe fall-offs in invertebrate life around salmon cages.

Because salmon cages are generally located in areas of low tidal activity and little current, waste products (principally excrement and uneaten food) accumulate on the sea bed under the cages. This leads to areas of the sea bed being poisoned, and can cause the blooms of toxic algae which affect, for example, shellfish. In extreme cases it results in 'red tides' which kill all marine animal life across a wide area.

There are other diseases and parasites associated with farmed salmon. Infectious Salmon Anaemia (ISA) and Gyrodactylus salaris are two. These can be transferred into rivers. A number of Norwegian rivers have been treated for Gyrodactylus - this basically involves pouring poison into the headstreams to kill every fish in the river. The rivers can then be restocked with healthy fish. This, so far as I am aware, is the only way of eradicating this parasite once it is present in a system.

Occasionally large numbers of fish escape from farms. They will run up the nearest river and attempt to spawn. We are coming to understand more about the genetic integrity of individual populations of fish, adapted by natural selection over many generations to best suit their particular home river. And it is clear that a large number of 'alien' spawners in a river with already reduced numbers of native fish could dilute the genetic integrity of a population. These escaped fish can also carry the diseases mentioned above into the rivers.

There are a few deep water, open sea farms that get round some of the problems, but they all dump chemicals and waste into the sea in a way that would cause an outcry if it occurred on land. The only responsible way to farm fish is in inland tanks or ponds, with all waste water treated before being returned to its source. I'm afraid it's very much a case of 'out of sight, out of mind' as far as what happens in the sea is concerned.

There is a small campaign running currently to bring the problem of salmon farms to peoples' attention, led by well-known Scottish fisherman and writer Bruce Sandison. For more information, have a look at

fredaevans 12-18-2002 01:51 PM

Gardener: One heck of a read!
Keep your eye's posted for more of this kind of information. The web connect really added some additional perspective.

OC 12-18-2002 02:53 PM

Thanks Gardener,

The info is great and the links are perfect.

Do you have any idea how fish farms are even able to get their foot in the door in places such as Scotland? I believe you have limited amounts of money your politicians can recieve to campian their bid for office so how does it happen?

Scott K 12-18-2002 08:17 PM

Read the article which is linked to in this thread:

flytyer 12-18-2002 11:15 PM


Thanks for the info and the perspective from your part of the world. Maybe, just maybe we fishermen who care about the resource will be able to get the policians to see and acknowldge that their is a problem. After which they will do something, resulting in improved fisheries and the removal of these threats.

I wholeheartedly agree that they only safe way to farm fish is in inland tanks or lined ponds with all waste water treated before being allowed into a waterway.

Gardener 12-19-2002 06:13 AM

Politics etc...
OC and Flytier, the trouble is that the fish farms were originally welcomed by many, including angling interests. The places where they are mostly found, notably the West coasts of Scotland and Ireland, are very poor areas where there is little industry and unemployment is a serious problem. Traditionally, crofting/subsistence farming was the principal occupation, but with changes in farming (and specifically the collapse in the wool market worldwide), it is increasingly hard to make any sort of living thereby, let alone one that you might regard as meeting 21st Century standards. There is a serious problem of depopulation, with communities dropping below the Ďcritical massí required to maintain schools and services, consequent loss of cultural heritage etc. So fish farming was (and is) regarded by many as a positive development in these areas.

Furthermore many people believed that aquaculture would relieve some pressure on wild fish stocks. As you are no doubt aware, there are efforts being made to stop the netting of salmon round the coasts of the British Isles, as well as on the high seas. It stands to reason that a ready supply of cheap, farmed fish would help to lower the price of wild salmon and make netting operations less attractive. It would have the further effect of reducing large-scale poaching, which remains a problem in some places.

So there were good reasons to welcome the fish farms initially. The problem is now that they do provide a source of income to poor areas; one which, even given the prices we have to pay for our fishing here, would probably never be supplanted by revenue from increases in fishing-related tourism. The actual job figures may be open to debate, but itís hard to argue for the total cessation of an industry that is now perceived as one of the economic lynchpins of these areas. One concern, for me, about the anti-farm protests is that they donít yet seem able to offer a viable alternative to the existing system, and without that any campaign seems rather hollow. This, I guess, is why Bruce Sandison is currently concentrating on trying to persuade consumers to buy alternatives to farmed salmon (eg Alaskan wild salmon); at the same time conservation bodies are working with the fish farmers to see if a less damaging system of aquaculture can be worked out.

OC 12-20-2002 09:40 AM

Scott K, boy that site you posted was really great. You have sportsmen from the left as well as the right posting on the internet in Canada. Down here all of our fishing sites have only strange land rights, right wingers that only fish in camo fatiges.

Gardener, as always with any enviro movement the emotions have to come first. Let us hope that your movement in Scotland will now have the time, funding and political power to help find alternative work for the peoples of the coast.

Many of us hope that the Salmon Farms will be able to be moved inland and into safe holding areas with proper treatment of effluent waste. Not sure that this will work untill the coastal net pen farms have been eliminated and total restrictions on imports are put on over seas farms. That would be hard with WTO policies now the mainstream. Reason we will not see inland fish farming untill the net pen farming is gone is cost.
I did some cost research for just polution control for a starting up farm on lets say one of our rivers in Eastern Washington.

First off one can not treat fish farm effluent with just UV disinfection as the organisms are to large and too many and the amount of UV light banks would be imense to get proper kill rate.
One would have to use chlorine gas disinfection with So2 de-chlor to nuteralize any Cl2 residual going into the river.

If the farms were required to meet pollution standards that city and counties are required to meet to treat thier sewage wastes on a river that has an ESA listing then there would have to be primary, secondary and a polishing treatment before disinfection.
This would have to be done as the farms waste is every bit as organic in content as a wastewater treatment plant. If the fish farm used 1 million gallons of water a day which seems likely for a small to average size farm and used the needed controls that a city wastewater plant does. The cost would be about 5 to 6 million dollars to start with the simplest facilities. The chemical and process control cost yearly not including labor and utilities would run about .5 million dollars a year.

Added cost for a fish farm would come from the amount of hazardous chemicals they use in disease control. These chemicals would not be removed from conventional treatment and would need to be stripped out by air towers or by chemical stripping. This cost would be an added 2 to 3 million dollars to build.

As we can see it will be hard for an inland farm to compete with a net pen farm with virtually no restrictions on it. But I want to point out that inland farms are happening, just this week got a call from Scotland about some pollution control equipment for an inland salmon farm in Eastern Washington that the Scottish company owns. I am looking forward to working with this company and seeing if we can make it cost effective and enviromentally safe.

DEERHAAWK 12-20-2002 04:38 PM

Pinks, Pens, Pesticides
Good day,
Sounds like the aquatic verson of "Soilen Green meets Frakenfish"! First line of defense, Hit them in the pocketbook. Tell all your friends and relitives to ask if its "farm raised" at the market, if it is, do not buy, unless from a responseable farmer. There must be some out there, anyone here know of any?, lets here what there doing!
Speynut, excelent eyeopener my friend, thanx

flytyer 12-20-2002 08:58 PM


Thanks for the info on the cost of doing inland fish farming. I still think this is the future of fish farming, although I'm very aware that until the far cheaper bay pen operations are regulated and made to quit poluting theinland farms will have a tough time competing. Glad to hear there is at least one being looked at as a possibility is Eastern Washington. Sure hope it can become a reality.

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