Sunday, December 27, 2009
“Sustainable” Salmon: A Slippery Selection
It isn’t news that most of the world’s fisheries are in crisis, and yet market demand for fish as an important protein source remains high. Salmon is a particularly popular choice, hailed for it’s health benefits, but when it comes to choosing a sustainable fish for dinner, salmon is one of the toughest to justify serving at the table. The majority of salmon available at the grocery store comes from fish farms in Chile and Norway, and is raised in submerged pens in protected bays, fjords, and freshwater lakes. Although aquaculture seems like a good way to take the pressure off of wild fish stocks, it is often a less sustainable option than one might suspect.
On the surface, aquaculture presents the perfect alternative to relying on dwindling wild populations. However, this hasn’t proven to be the case. In fact, salmon farming can actually aid in crippling wild stocks, as it is common for farmed salmon to escape their submerged pens. In Chile, where salmon is a non-native species, its introduction to the local ecosystem can be harmful to existing species. Once in open water, farmed salmon can also interbreed with wild salmon, muddling natural genetics, as well as spread diseases and parasites. In recent years, Chilean farms (owned by the giant Norwegian company, Marine Harvest) have come under scrutiny due to an outbreak of an infectious fish virus. Farm-bred fish are particularly susceptible to disease, a consequence of crowded pens, and are given high doses of antibiotics to combat bacterial illness.
Salmon farms can also be harmful to the surrounding environment, contaminating local ecosystems with high concentrations of fish waste and excess feed. The increase of nutrients from fish waste depletes oxygen in the water and makes it difficult for other animals to survive in the area surrounding the farm. These issues exist regardless of whether salmon is raised organically or conventionally. Additionally the process of manufacturing fish feed, maintaining farms, and processing the fish, requires huge inputs of energy and resources.
When talking about sustainable seafood, it is important for us to pay attention the bigger picture. It is true that if I buy farmed salmon from Chile, I have not purchased a fish from a potentially at-risk population. However the impact fish farming can have on wild fish and on the environment, and the amount of antibiotics and effort it takes to keep farmed fish “healthy” makes me think twice about choosing salmon. Several non-profit marine protection groups, like the Blue Ocean Institute, have rating systems to help consumers navigate which type of salmon is the most “sustainable” choice, and increasingly these tools are showing up in grocery stores around the world. In the case of salmon, wild Alaskan is often a better pick than the internationally farm-raised version. It is important for us, as conscientious consumers, to make informed decisions when buying fish, but perhaps it is also time for us to take a more proactive approach to encourage fish farms to follow a more sustainable model.