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The Once and Healthy Salmon Farm

What's the difference between wild salmon and those from a fish farm?

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How safe is seafood from a salmon farm?

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Most scientists agree that seafood rich in omega-3 fatty acids is one of the most nourishing of all foods. A variety of studies have shown that in most individuals, fish could help fight cancer, cardiovascular disease, immune function, brain health, rheumatoid arthritis, etc. Cold water oily fish including sardines, herring, mackerel and anchovies are excellent sources of omega-3 fatty acids, but salmon -- the fish chosen by most Americans -- is near or at the top of the list.

Prior to the early 1960's, when salmon farming began in Norway, the only choice was the wild-caught variety of salmon. Undammed river stocks were abundant in the Pacific, but it was largely a seasonal delicacy, and one relished for its incomparable taste and nutritional value.

The Atlantic salmon fishery had been in decline for over 100 years for a variety of reasons, including dams, overfishing, increased levels of pollutants and higher water temperatures. The EPA has designated the Atlantic salmon endangered -- thus, any Atlantic salmon on a restaurant menu is farmed.

This was all before the era of factory trawlers and aquaculture, which has further contributed to drastic reductions in wild fish stocks almost everywhere. So what if salmon are farmed? Just what is salmon farming and what are the implications?

  • The salmon raised on a farm was probably born in a plastic tray instead of leaping up rocky streams; the first 3 years of its life were spent like a marine couch potato.
  • These young fish are vaccinated to survive the diseases that ravage it and the tens of thousands of others where it lives, in acres of net-covered pens tethered offshore.
  • It was likely dosed with antibiotics to ward off infection or fed pesticides to protect it from bloodsucking sea lice.
  • It was fed a diet of synthetic pigment to avoid what would otherwise be its color of unappetizing pale gray.
  • If all this was not bad enough, to the farmed variety and their human consumers, the same parasitic sea lice in the pens prey on and infect juvenile wild salmon when they swim past on their way from inland rivers to the ocean.
  • Escapees from the pens interbreed and hybridize with wild fish and spread parasites, pollution, and infectious diseases, and they genetically weaken wild fish populations.
  • Their waste and uneaten feed smother the sea floor beneath these farms, generating bacteria that consume oxygen vital to shellfish and other bottom-dwelling sea creatures.
  • According to a new analysis by government advisers in Britain, among 100 different worst-case examples of fruit, vegetables, meat and other foodstuffs polluted by pesticides over the past five years, farmed Atlantic salmon comes out worst. Every fish sample in the batch tested by scientists was found to contain at least three toxic chemicals.

Perhaps the direst of all these consequences is that these farms worsen the problem they were hoping to eliminate: filling the demand from growing world populations for seafood and allowing wild stocks to regenerate. This is because the captive salmon, which are carnivores, require a diet of fish, unlike vegetarian catfish that are fed grain on farms. Some 2.4 pounds of wild fish are required to produce one pound of farmed salmon. That means grinding up a lot of sardines, anchovies, mackerel, herring and other fish is required to produce the oil and meal compressed into pellets of salmon chow. This does not take the strain off wild fisheries, but adds to it.

There is a silver lining for salmon lovers in this dreary farmed fish story, and it's in Alaska. The healthiest populations and habitats are there, and the Alaska Salmon Fishery recently received the an award for sustainability from the Marine Stewardship Council. Because these fisheries are so well-managed, fresh-caught wild salmon are available nearly eight months of the year and high quality "frozen at sea" (FAS) line-caught fish are available during the interim.

This article was authored by Chicago-area conservationist Donnie Dann and appears here by permission.

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