Instead, these buyers either rely on partnership with an organization like Seafood Watch to identify better performing shrimp farms, or, they can look for a certification from an independent, nonprofit assessing agency. (Only about 3 percent to 6 percent of shrimp farms are assessed, which is a voluntary process that the farms pay for.)

The certifications a consumer in the United States is most likely to encounter are the Global Aquaculture Alliance (G.A.A.), which has developed standards called the Best Aquaculture Practices (B.A.P.). There is also the Aquaculture Stewardship Council (A.S.C.), which is more established and widespread in Europe.

If you see any of these abbreviations listed on the label of your frozen shrimp or at your fish market, you can go ahead and buy with confidence. (Look for at least a two-star B.A.P. rating, out of four stars.)

While all these endorsements address the environmental sustainability of the farms, only the B.A.P. and A.S.C. take fair labor practices into consideration. (Seafood Watch is developing tools to do this in the near future.) And, none of them can tell you anything about the quality of the shrimp’s flavor and texture — for example, whether the shrimp have been treated with chemicals after harvesting, whether they’ve been mishandled during processing or whether they’ve been thawed and frozen several times over, all of which can leave them soft and watery.