Wild Alaskan Salmon Is Still the Best Choice

But smarter ways to farm salmon are available

Posted: 19-Jul-2006; Updated: 16-Oct-2007

Wild Alaskan Salmon Is Still the Best Choice

Salmon are a good source of lean protein. But where they come from can affect how healthy they are to eat.

Growing 1 pound of farmed salmon requires 3 pounds of wild fish, robbing marine animals of a primary food source.

If you eat fish, chances are you eat salmon. In 2001, salmon took over the number three spot in America's top seafood choices. In 2004, Americans ate almost twice as much of the pink-fleshed fish as they did in 1995.

A big part of the soaring demand is the fish's wealth of omega-3 fatty acids, which studies suggest have a wide range of benefits, from lowering risk of stroke to reducing depression.

Another reason for the explosive growth in salmon consumption is the expansion of salmon farming—which has helped push down the price and make it available year-round. But remember when ordering it at restaurants or trawling for it at your local seafood counter: not all salmon are created equal.

Typical farmed salmon have health and ecological drawbacks

The taste differences between the four most popular wild species from Alaska—chinook, coho, sockeye and pink—and farmed salmon are substantial and are reflected in their prices. But taste isn't the only thing that sets them apart.

Typical farmed and wild salmon have substantial distinctions in how healthy they are to eat. There are also considerable environmental drawbacks to salmon farming—although some salmon farmers have committed to important steps forward. The bottom line is: eating wild salmon from Alaska is better for your health and the environment, for now anyway. But change is underway. (See sidebar.)

Eat smart ... here's how to start

Now, there are good reasons to buy farmed salmon—wild salmon may not be in season or it may be too expensive. But if you choose farmed salmon (usually Atlantic salmon, a species that is commercially extinct in the wild), you should limit those meals (or find a source of farmed salmon that meets strong contaminant standards). Find out how much is recommended for your gender and age group.

Finding smarter ways to raise salmon

If you care about the environment and especially our oceans, here's the full scoop on farmed salmon.

Problem

Typical salmon farming robs essential food sources from the entire marine food chain. Unlike some farmed fish, salmon are carnivores. Their feed includes fishmeal and fish oil made primarily from small fish, such as sardines, capelin and menhaden. On average, it takes roughly 3 pounds of feed fish to produce one pound of farmed fish. These fish are an important food source for lots of other ocean life, including striped bass, bluefish, whales, sea birds and seals.

Better Way

Lower the fishmeal and fish oil content of the salmon feed and substitute with vegetarian options.

Problem

Some farmed salmon is significantly higher in PCBs and other toxins than wild salmon.

Better Way

Wild pink and chum salmon are especially low in contaminants thanks to a plankton-rich diet. Most other wild salmon from Alaska are, too, because they eat a mix of fish, krill and other small animals from cleaner waters. Feeding farmed salmon less wild fish or using forage fish from cleaner South American waters reduces the concentration of toxic substances.

Problem

Salmon farms produce concentrated waste that heavily pollutes surrounding areas. By one estimate, an average farm may release an amount of nitrogen, phosphorus, and fecal matter roughly equivalent to the nutrient waste in untreated sewage from 20,000, 25,000, and 65,000 people, respectively. Farmed salmon are raised so closely together that sea lice become a problem, and the lice can spread to wild fish. Crowded pens are also breeding grounds for disease. Antibiotics, parasiticides, and other chemicals used to treat disease and parasite outbreaks can leak into surrounding waters.

Better Way

Use vaccines and other preventative measures to minimize disease and thus drug usage. Move fish farms away from key wild salmon runs. Adopt integrated systems where mussels and seaweeds are grown near salmon pens to recycle nutrient wastes.

Problem

Farmed salmon can escape and harm wild populations. The effect of salmon escapes depends on where the fish are farmed. In the Pacific Ocean, where Atlantic salmon are non-native, they could compete with their wild counterparts for food, spawning sites, etc. In the Atlantic Ocean, where wild Atlantic salmon are endangered, they could also interbreed and alter the makeup of the wild gene pool.

Better Way

Use tough nets and other measures to minimize escapes. Tag salmon, so farmers can be held accountable for fish that escape. Support research on how to raise farmed salmon in closed containers.

A salmon's diet may be hazardous to your health. See full graphic »

Advertising claims that there is little or no mercury in salmon miss the point. Cancer-causing PCBs are the toxins to be concerned with when it comes to farmed salmon, and some farmed salmon are loaded with them, containing three to six times the World Health Organization’s recommended amount of PCBs and dioxins.

Why? Their feed, which includes large amounts of fishmeal and oil, is contaminated with PCBs. Unlike some other farmed animals like hogs, which are bred to be lean, farmed salmon are fattened up. While the fat in salmon is full of heart-healthy omega-3 fatty acids, the extra fat also increases the storage capacity for carcinogenic toxins such as PCBs.