I’ve laid out information on both wild and farmed salmon. There are many other issues that confront healthy populations of wild salmon. Besides the effects of farmed salmon in the vicinity of spawning grounds, farming also can create problems for the salmon. Salmon require very specific riverbeds and water flow for spawning and the growth of the new salmon. Sediment runoff, diverted waterflows and pesticides used on farms can adversely affect the salmon population.
The dams on the rivers have created an obstacle for spawning salmon to swim upsteam and the small fry to swim downstream.
The question comes up about how we as consumers should vote with our dollars as we purchase our seafood. Most harvests are carefully controlled. The Pacific Salmon is managed by scientists setting an allowable catch level based on the “biomass” or total amount of that type of fish in the oceans. Catch levels are set well below the number of fish that can be sustainably caught. The Alaska Seafood Marketing Institute has a lot of great information if you want more about catch levels (www.alaskaseafood.org).
Because the population is well managed, any purchase of wild Pacific Salmon is by definition sustainable. For many of us, if we can’t get fish quickly from the boat, frozen supplies are a great alternative. Frozen fish are generally processed very soon after catch and when thawed properly, are as fresh as anything we can get here in Huntsville. Costco and Sams have even started carrying wild Alaskan salmon filets in their frozen sections.
As a rule, avoid farmed Atlantic salmon. Even farmed responsibly by addressing the issues I mentioned, it still takes about 3 pounds of harvested fish to grow 1 pound of farmed salmon. If you do buy farmed salmon, make sure the farm is not using antibiotics, provides sufficient room for the fish to eliminate sea lice and other diseases and minimizes the impact of the waste on the surrounding environment. They must use closed pens to prevent the escapes that are creating havoc in some wild salmon populations. The other farming options are full tank farming where the fish farm is not in floating alongside the wild population. There are a few tank farms for salmon, but it is more expensive to farm this way. Many other types of seafood can be farmed economically in tank farms.
If you want more information about purchasing sustainable seafood, the Monterey Bay Aquarium publishes the Seafood Watch which is a list of fish that is well managed or farmed in environmental friendly ways. They publish a variety of pocket guides for reference – http://www.montereybayaquarium.org/cr/cr_seafoodwatch/download.aspx
Seafood is good for us and just tastes so darn good – be assured that you can purchase seafood that does not adversely affect the population or environment!