Climate change and development (and its resulting pollution in coastal areas), overfishing, and even salmon farming are threatening the world’s fish supplies. For example, waste from most salmon farms passes directly into the ocean. Diseases and parasites from farmed fish can also spread to wild species. Some farmers use antibiotics to control disease among salmon, only fostering the growth of drug-resistant bacteria. When farmed salmon escape from ocean pens, they threaten wild stocks by competing for food and spawning grounds.

Despite a recent review that suggests the collapse of current commercial fisheries by 2048, a return to abundance and biodiversity is possible—if we work together to restore marine environments through pollution controls, strict fishing quotas, and careful ecosystem management. When buying seafood, look for wild-caught or farmed fish from operations that don’t use antibiotics or supplemental hormones and that test low for environmental contaminants like dioxin, mercury, and polychlorinated biphenyls (PCBs).

To eat four ounces of omega-3-rich fatty fish twice a week may also require sampling a wide variety of watery fare to save dwindling stocks of some species. Here are the most sustainable choices from different areas with notes (where applicable) on the best catch and management practices:

Arctic char (farmed)
Barramundi (U.S. farmed)
Catfish (U.S. farmed)
Clams (farmed)
Cod, Pacific (Alaska longline)
Crab, Dungeness or stone
Halibut, Pacific
Herring/Sardines (Atlantic)
Lobster, spiny (U.S.)
Mussels (farmed)
Oysters (farmed)
Pollock (Alaska wild)
Salmon (Alaska wild)
Scallops, bay (farmed)
Striped bass (wild* or farmed)
Sturgeon/Caviar (farmed)
Tilapia (U.S. farmed)
Trout, rainbow (farmed)
Tuna, albacore (U.S. or British Columbia troll or pole); skipjack (troll or pole)
* Limit consumption due to possible contamination.
Also go to www.seafoodwatch.org for a downloadable chart on reasonable alternatives and which seafood to avoid.