Commentary and Photography by Alexandra Morton

There are husbandry practices within the salmon farming industry which need to be scrutinized by the Minister of Health for their impact on human health.

Chinook salmon smolt - July 31, 2001 - Broughton Archipelago

Sixteen years ago I moved to a remote archipelago off the coast of British Columbia to study the natural history of killer whales. Four years after my research began, salmon farms started towing into the area to raise Atlantic salmon. I am writing to you after 12 years of closely observing the salmon farms in my study area, and noticing aspects of farm salmon husbandry which can not be acceptable to human health. I would never feed my children a farm salmon.

In 1993, a company called Scanmar used Atlantic salmon stock which were infected with a triple-antibiotic resistant strain of Aeromonas salmonicida - the causative agent for the fish disease, furunculosis. This bacteria was resistant to all antibiotics approved for use in salmon farming and it spread 10 km to infect several B.C. Packer farms, another company raising salmon. Despite the fact that the farms straddled prime, protected, wild chinook salmon habitat, and the provincial Ministry of Fisheries, Food and Agriculture declared the spreading disease an "emergency situation", the federal Department of Fisheries and Oceans allowed the diseased stocks to remain in the net pens and prescribed oral administration of the antibiotic, Erythromycin.

What caught my attention was in the DFO publication "Streamtips" (summer 1992) DFO had published an "Erythromycin warning." "Fish treated with erythromycin, including spent adults, may not be used for human consumption and under no circumstances may the drug be used orally... in food fish,” it stated. It occurred to me that DFO had compromised its own concerns about this important antibiotic, the public health and the wild salmon stocks, under pressure from salmon farmers. The wild salmon, incidentally, crashed across all age-classes in that area, that year, and have never recovered.

Every fall I assist in capturing wild coho broodstock for enhancement. Several days following an escape of 30,000 Atlantic salmon from a nearby salmon farm run by Stolt, Atlantic salmon appeared in the stream where we were taking the coho. We froze the first three we caught, the fourth I sent to the Provincial Ministry of Fisheries, and from the fifth I took bacterial swabs and sent them to the Fish Pathology Lab at the University of Guelph. All these fish had open sores, encrusted with yellow pus and we were concerned about this infection spreading to the endangered coho. I wanted to identify the pathogen, before we started losing the endangered coho broodstock.

The lab report found two bacteria - Serratia plymuthica and Serratia liquefaciens. Neither of these bacteria were recognized by fish scientists I contacted, although they have been responsible for death among farmed Atlantic salmon in other parts of the world. So I called my doctor. She was familiar with these ecoli-like bacteria - common in sewage. What really alarmed me was their resistance to 11 out of 18 antibiotics tested. Since this discovery, the province has been splitting hairs regarding my methodology, the source of the infection and fish, but MY first reaction was that I should have been wearing gloves when I handled that fish.

People throughout B.C. are catching escaped farm salmon with no idea of the drug history of those fish. Did they escape mid-treatment, have they completed a safe withdrawal period? I have talked with hatchery workers, encountering Atlantic salmon during broodstock takes who smoked and ate the farm fish. This low temperature cooking method will not kill the bacteria present.

People are also fishing in the immediate vicinity of fish farms - which do not advertise drug and pesticide treatments underway in the net pens. Since the nets do not prevent medicated food pellets from getting outside the pen - the entire wild food chain is susceptible to uptake of the drugs. Antibiotic residues and resistant bacteria persist in the waste which accumulates under salmon farms.

Fishermen and B.C. sea food consumers are therefore at risk of antibiotic contamination, a recognized, growing threat to human health. This situation is aggravated by the practice of siting of salmon farms in the areas of highest wild biomass production in this archipelago, locations which were protected for a fleeting time by the province as "red zones" where no fish-fish farming could be conducted (Coastal Resource Interest Study 1989).

If Guelph University's tests were accurate, at least some farm salmon harbour seriously drug resistant pathogens. Disturbingly, the fish I sampled was resistant to human medicines such as Penicillin, Ampicillin and Erythromycin.

There are no towns in the area - Echo Bay has only 40 people- and so there are no municipal sewers which could have exposed this fish to drug resistant sewage.

As an aside, there are rumors, which I have not attempted to substantiate, of people experiencing toxic shock as a result of handling fish in the farm salmon processing plants. People believe it is due to exposure to drug residues in the fish to which the person is allergic.

My second area of concern is pesticides. Some of the farms coat their entire nets with a red anti-foulant paint called Flexgar to prevent growth of mussels, barnacles and other species. In a period of months, this paint flakes off the nets and the net has to be repainted. Unbelievably, the label for this product specifically states "Toxic to aquatic organisms. Do not contaminate water. Do not allow chips to enter water" with a skull and crossbones clearly visible! And yet not only do gallons of paint chip off each net into the water, the farm fish feed among these paint chips, with mouths agape, sucking in water along with each pellet. It seems impossible that they are not consuming the paint chips flaking off the five submerged sides of the net pens as they feed. Are other Canadian agricultural food producers raising livestock in containers coated with toxic paint?

The other salmon farming pesticide which is not approved by its manufacturer for use in the marine environment is Ivermectin. Ivermectin is coveted by salmon farmers to rid their slow-swimming, high-density fish stock of sea lice - a big issue for salmon farmers. In a policy, which seems negligent at best, B.C. salmon farmers are not allowed to put Ivermectin in the water as a "pesticide", unless they soak it into a food pellet, which many marine organisms will find attractive, and then throw it into the water as a "pharmaceutical".

On February 7, 2000, 7,000 farm salmon died from an over-dose of Ivermectin, illustrating the narrow margin between efficacy and toxicity for this drug. The problem is not so much that a vet made a mistake, but that this lethal chemical is being used at all in a fish farm sited on commercial and sport fishing grounds. Nearby this farm an exclusive fishing lodge attracts luxury yachts with helicopters on the upper decks and these people go out and trap prawns near the salmon farms using Ivermectin. In addition, a commercial fishing fleet works in the area harvesting prawns and other species and ships the seafood all over the world.

Prawns are bottom feeders, inhabiting places where currents slacken and drop particulate matter and Ivermectin-laced pellets are now dropping on them. If the prawns don't outright die, they will carry this persistent pesticide for a long time. Four nanograms of Ivermectin per liter of water kills shrimp (that's one ounce per 10,000 Olympic-sized swimming pools) and 1000 degree days are required to withdraw salmon from Ivermectin. It is so toxic its manufacturer, Merck, has not approved or even tested the drug for use in water. It was found to kill all life in the sediments underneath salmon farms, preventing decomposition thus creating seriously toxic dumpsites.

Ivermectin is benefiting from a legal loophole. A "pesticide" must attack a parasite directly, but Ivermectin has to applied to the host, to the point of almost killing that host, to reach the parasite and therefore it is a "pharmaceutical". The Provincial Abbottsford Veterinarian Lab uses this loophole to give salmon farmers permission to use Ivermectin - even though the manufacturer knows it is too toxic to even attempt approval for use in water. This behaviour seems irresponsible, threatening the health of seafood consumers. In Scotland, vets are using the same loophole and 11% of farm fish tested positive for Ivermectin in 1994, but who is testing the wild food chain adjacent to the farms?

These are some of the reasons I would never feed my children farm salmon and why I am asking you to examine husbandry practices on salmon farms. It has become abundantly clear to me as I observe this industry that what is damaging to our environment is damaging to our bodies.

The salmon farms belong in tanks, isolated from resources used by the public in the same manner as other animal feedlots.

END NOTE: Alexandra Morton is a biologist, author - and voice in the wilderness. She lives off the coast of Northern Vancouver Island in an area where there is a heavy concentration of fish farms, and for years has been warning of the ecological dangers this industry poses.