I just watched Happy Feet. Fun movie, and it also provided a useful link to the Monterey Bay Aquarium (mbayaq.org) which happens to have info about fish to eat, and not eat. They have a lot of fish on their lists, and their "avoid" list was built based on many different factors. Some factors include "too much mercury" or "farming doesn't meet our standards." Good reasons, but not eating such a fish won't make much of an impact. Much better reasons, in my opinion, are "population in extreme decline," "endangered," "very destructive bycatch" or, in the famous dilemma of the Chilean Sea Bass aka Toothfish, "endangered & 50% of harvest is poached."
And so, here is my cleaned up list of fish. Please do not eat the following: Chilean Sea Bass "Caviar"/Sturgeon Bluefin Tuna Atlantic Cod MonkFish Dog fish Spiny Lobster (Caribbean) Rock Fish (some sp. overfished) Scallops, Mid-Atlantic (North-Atl is OK) Shrimp (destructive bycatch, esp: Black tiger shrimp, Tiger prawn, White shrimp )
Believe me, as a sushi lover it's tough to put fish like Bluefin Tuna up there, but we're the very folks responsible for it's demise. (xposted)