We've put out (most of the work was actually done by the Monterey Bay Aquarium) a guide to seafood choices with three catagories: Best choices (fish that are abundant, well managed and caught or farmed in environmentally friendly ways), Alternative Choices (good alternatives but with some concerns about how they are caught or farmed), and Avoid! (species that that are overfished or caught/farmed in ways that are environmentally harmful).
Catfish (US farmed) Clams (farmed) Softshell clams (wild-caught) Dungeness crab (Canada) Croaker (Atlantic) Halibut (Pacific) Herring (Atlantic) Lobster (Spiny, US) Mussels (farmed) Oysters (farmed) Pollock (wild caught) Salmon (wild caught) Striped bass (farmed or wild caught) Sturgeon caviar (farmed) Tilapia (farmed) Rainbow trout (farmed) Albacore, Bigeye and Yellowfin Tuna (troll or pole caught)
Alternatives:
Basa (farmed) Black Sea Bass Bluefish Hard shell clams (wild caught) Blue crab Rock crab King crab (Alaska) Imitation crabmeat or surimi Haddock (line caught) Hake (Red or Silver) Lobster (New England) Mahi mahi or Dolphinfish Oysters (wild caught) Scallops (Bay) Scallops (Deep-sea, Canada) Scup Shrimp (Canada) Shrimp (US farmed raised) Squid Swordfish (US) Tilefish (Mid-Atlantic) Albacore, Bigeye or Yellowfin Tuna (longline caught) Tuna (canned dolphin-safe)
Avoid!
Chilean Sea bass Cod (Atlantic) King crab (imported) Dogfish (Atlantic) Flounder (Atlantic, all species) Haddock (trawl caught) Hake (White) Halibut (Atlantic) Monkfish Orange Roughy Salmon (farmed) Scallops (Deep sea mid-Atlantic) Sharks Skates Shrimp (imported farmed or wild caught) Red snapper Sturgeon caviar (imported wild caught) Swordfish (imported) Tilefish (Southeast) Tuna (Bluefin)