Yaty and I went to the Aquarium on our last trip to California, and I picked up a few Seafood Watch wallet cards:

A program of Monterey Bay Aquarium designed to raise consumer awareness about the importance of buying seafood from sustainable sources. We recommend which seafood to buy or avoid, helping consumers to become advocates for environmentally friendly seafood. We're also partners of the Seafood Choices Alliance where, along with other seafood awareness campaigns, we provide seafood purveyors with recommendations on seafood choices.

[ Monterey Bay Aquarium: About the Seafood Watch Program ]

The display they made in conjunction with this was quite informative. For example I figured the best salmon was farm-raised because it wouldn't impact the wild salmon. In fact it's quite the opposite. Farm-raised salmon actually damages the wild populations.

The more you know... and of course, Knowing is half the battle...