There was an interesting question raised today in the New York Times asking why farmed salmon is worse than farmed tilapia. One of the main differences is the fact that salmon is raised in floating feedlots in Chile, Canada and Europe. They require to be in salt water whereas tilapia can be raised in tanks or ponds and require no fish or animal protein in their feeds.
The feedlots create a whole set of issues the farmed salmon have been known to escape and interfere with the wild salmon population The farmed salmon have a lot of parasites and diseases that are passed onto the wild salmon close to the lots. Studies have also shown that farmed salmon have higher concentrations of PCB’s and Mercury than wild. They also tend to be contaminated with antibiotics as they are treated with large quantities to prevent disease. They have to live in cramped conditions and even swallow their own waste.
Because salmon are carnivores it takes a lot of fish to feed them and decreases the populations of other fish in the process.
So yet again interesting points to consider but the conclusion is to buy wild salmon, better for the environment, the fish and our health.
Sources:
- http://www.sectionz.info/issue_1/wild_salmon.htm
- http://www.nytimes.com/2010/04/13/science/13qna.html?ref=science