Choosing sustainable seafood can be overwhelming. Fish is healthy, and supposedly three servings a week is ideal. But maybe not if that three servings is full of mercury, and not if the fish is being hunted to the point of extinction. So what's a seafood-loving girl to do?
I carry the Seafood Watch iphone app with me on every trip to the fish market. They also make a wallet chart that you can pick up at Whole Foods or other such places. A quick glance will tell me whether a potential purchase is a "Best Choice" a "Good Alternative" or something to "Avoid". If you want to delve deeper, it will also explain the rating to you. I used to avoid seafood all together because the subtleties were too overwhelming, but this tool makes decision-making much easier. That said, food fraud runs rampant in the seafood industry, so make sure your fish market is knowledgeable and trustworthy so you don't end up with catfish instead of snapper (But you wouldn't buy snapper, right? It's on the "Avoid" list.)
Where I live there are many seafood peddlers to choose from. There's the small, locally-owned fishmonger, which has the best quality fish around but not always the most sustainable choices. Then there's the local food co-op, which has plenty of sustainable options at crazy high prices (though their little packages of leftover lox ends are super cheap and have become a staple for me). I've found that Trader Joe's, at least last time I checked, doesn't carry very many sustainable options in their freezer. Even the generic grocery store in town has a pretty fine seafood counter, which is where we ended up last night in our search for mussels.
I was on the hunt for an iron-rich snack, because I'm starting to suspect I'm running a little low in the iron department. Mussels are a great source of iron, and according to my handy-dandy iphone app, farmed mussels are a "best choice" purchase because they are raised in an environmentally responsible manner. The seafood counter at Big Y had bags of live mussels farmed in Prince Edward Island (not exactly local, but not Thailand either). The price: $5.50 for 2 lbs. Sold! We took those puppies home and made an amazing meal by steaming them in a creamy wine sauce. A big win for my iron intake, my wallet, and sustainable seafood!