Fact Sheets

Salmon Farming

  • As in any high-density farming situation, many changes must be made to the natural environment in order to get a crop to market, and make a profit. The essential difference is that, on land, many of these effects can be contained. In the water, nothing can be contained -- often, not even the crop being raised.

  • Like battery chicken farms, farmed salmon are stocked in an extremely dense and stressful environment. They require many things to keep them healthy while they swim, thousands together, in small circles, in big nets. Some of the things they eat, are washed with, have injected into them or are subjected to are discussed below.

  • Special feed or fishmeal: Uneaten feed, along with fish faeces, falls to the ocean floor under the cages where it collects and changes the nutrient quality of the water. Often, the seabed beneath these cages becomes so filthy that divers must be sent down to clear the area.

  • This excess food attracts some species (other fish, shellfish), but it also disturbs the marine environmental balance in that area. In addition, it is suspected that this change in nutrient balance is responsible for some of the toxic algae blooms ('red tides') which cause shellfish poisoning. For the first time in memory, Lough Swilly had a 'red tide' in November 2000.

  • Chemicals: More than 19 different chemicals are legally allowed as baths for salmon parasites and disease, or as defoulants for cages and lines. These are used in the water: obviously, they do not stay within the cages or nets.

  • Salmon are sometimes immunised by injection as well. This has resulted in antibiotic resistance to some diseases, with implications for the humans who eat the fish ('super-bugs').

  • Other drugs: Anesthetics and hormones are also used in salmon farming.

  • One disease, for which there is no cure, infectious salmon anemia (ISA) decimated Scottish salmon farms in 1998, and cost the Scottish government more than £100 million in control and compensation -- taxpayers' money that could have had other uses. A similar ISA outbreak in New Brunswick cost Canadian taxpayers CDN$50 million.

  • One of the worst parasites for farmed salmon is sea lice. Infestations can literally eat the salmon alive. In Ireland, they use a chemical called 'Cypermethrin' to treat sea lice. Cypermethrin is a synthetic pyrethroid chemical, also used as sheep dip. Cypermethrin is 100 times more toxic to aquatic life than it is on land. It is considered so environmentally dangerous that its use on fish farms is illegal in Canada and Scotland. "As little as a small cupful of cypermethrin . . . has the potential to kill fish and insects over several kilometres in a sizeable watercourse. The effect can be as devastating as an Exocet missile in the water." (Scottish Environment Protection Agency, 13 June 1997.) Would you want your children to swim in sheep dip?

  • Farmed salmon are gray because they don't mature in the same way as wild salmon, nor is their diet the same. In order to make their flesh pink, they are fed a special dye, astaxanthin. The Swiss pharmaceutical giant, Hoffman - La Roche, have named their astaxanthin product 'Carophyll Pink,' describing it as 'the reliable source of pigment which provides your fish with a nature identical colour' [sic]. It comes with a colour chart of shades from palest pink to rosy red: you can choose what tint of dye you would like to eat.

  • Farmed salmon sometimes escape because of damage to nets by storms or by seals, for example. When they do escape, it is not by ones or twos, but by thousands. (In British Columbia, for example, it is estimated that more than 345,000 farmed salmon escaped between 1991 and 1999.) Escaped salmon - and whatever diseases or parasites they carry - can infect wild fish.

  • It is acknowledged that sea lice on farmed salmon can be spread to wild fish; salmon and sea trout are susceptible. Sea trout are almost extinct in many angling rivers in Ireland (a major tourism revenue earner), and wild salmon are under threat. The Crana River, in Inishowen, is one of Donegal's finest wild salmon rivers. They have seen their wild salmon eaten alive by sea lice.

  • In Norway, no salmon farm is allowed within 20 km of a wild salmon river. In 1994, the Ministry of the Marine in Ireland accepted a report that recommended that all fish farms be kept more than 20 km away from any wild salmon river, but because of pressure from the aquaculture industry, the report was never officially published (printed copies of the recommendations do exist, however). In Lough Swilly, the Crana River is only 3 1/2 km from a fish farm licensed by the Ministry.

  • Escapees can inter-breed with wild fish, producing offspring which are no longer true Irish wild salmon. Many of the salmon that anglers catch in the Crana River, for example, are misshapen half-breeds. In Norway, where salmon farming began, the government became so concerned about inter-breeding and dilution of the salmon gene pool, that they have established a 'gene bank' of the original wild species lines, so that they still have their true 'wild' salmon genes for later breeding. In Ireland, we have no original gene bank.

  • Bright lights, spotlighting the cages, are sometimes used at night to encourage growth.

  • Farmed salmon are carnivorous. It takes four pounds of processed wild fish to produce one pound of farmed salmon. The fish they are fed is suitable for human consumption, and could have been used for that purpose.

  • Two months ago, the EU's Scientific Committee for Food found that fish oil and fishmeal have the highest levels of toxic industrial chemicals such as dioxins. Yes, dioxins are in everything - but fish oil and fishmeal are the most heavily contaminated of all these feed materials, and are found at higher levels in carnivorous fish, like salmon, both wild and farmed. (See New York Times, 18 Dec 2000). These EU scientists advised that we cut our consumption of fish considerably.

  • The Blue Flag beach at Portsalon brings tourists from all over the world. Voted by The Observer as 'one of the ten best beaches in the world' (it was Number 2), why risk having it despoiled by fish cages? Why risk losing the Blue Flag? Rathmullan has already lost theirs; Portsalon currently has the only Blue Flag on Lough Swilly.

  • A recent Norwegian research report (January 2001) notes that 'salmon farming may gradually move out of the country, because of stringent government regulations.' New salmon-farming licences have not been granted by the Norwegian government for years. Two countries mentioned where salmon farming was likely to move were Chile ('with few and liberal regulations, an investment-friendly policy and a frail administrative infrastructure') and Ireland (where they 'also practice a relatively investment-friendly policy.') Why should Ireland choose to increase what Norway has seen fit to regulate so strictly? What does Norway know that Ireland doesn't? Or, more accurately, what have they learned that we refuse to acknowledge?
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Fact Sheets:

Shellfish Farming

Salmon Farming

Environmental Impact Assessments & Statements

Sea Lice