Experts originally had hoped that aquaculture, or fish farming, would help alleviate the fishing pressure on the oceans by raising fish in coastal net cages, inland ponds and other methods. Today, one-third of seafood comes from aquaculture and that proportion is expected to increase to 50% by 2020.

However, if not managed correctly, aquaculture does more harm than good. For example, salmon feed requires approximately three pounds of wild fish protein to raise one pound of farmed fish. The average salmon farm is a series of net pens floating along the coast, allowing feces, uneaten feed and other wastes to circulate directly into the surrounding ocean environment, untreated. Scientists are also concerned that the closely quartered fish easily spread disease to one another (consequently requiring antibiotic treatment) or to nearby wild fish. The farmed salmon can also escape from their net pens and compete with wild populations of fish for natural resources. For these reasons, Seafood Watch recommends that you avoid farm-raised salmon.