News Business & Policy This Acronym Will Help You Choose Ethical, Sustainable Seafood You'll never get stuck wondering what to buy at the seafood counter. By Katherine Martinko Katherine Martinko Twitter Senior Editor University of Toronto Katherine Martinko is an expert in sustainable living. She holds a degree in English Literature and History from the University of Toronto. Learn about our editorial process Updated December 14, 2020 02:32PM EST Fact checked by Haley Mast Fact checked by Haley Mast LinkedIn Harvard University Extension School Haley Mast is a freelance writer, fact-checker, and small organic farmer in the Columbia River Gorge. She enjoys gardening, reporting on environmental topics, and spending her time outside snowboarding or foraging. Topics of expertise and interest include agriculture, conservation, ecology, and climate science. Learn about our fact checking process Shana Novak / Getty Images Share Twitter Pinterest Email News Environment Business & Policy Science Animals Home & Design Current Events Treehugger Voices News Archive Have you ever stood in front of the seafood counter, wondering what to choose? It can be daunting figuring out what the most sustainable and ethical options are. In order to ease the decision-making process, here's a handy acronym known as the "Good Fish" rules. They come from Becky Selengut's cookbook by the same name, in which Selengut suggests using the acronym FISH to remember what to buy. "F" is for Farmed This does not apply to just any farmed fish. You want to look specifically for farmed mollusks and shellfish (excluding shrimp), which are considered to be the most ethical form of seafood. Shellfish such as oysters, mussels, and clams filter nutrients from the surrounding water and do not require feeding; they grow a meaty muscle meat that is rich in omega-3s without the mercury levels found in other fish. They also absorb carbon to make their shells. Most farmed finfish is best avoided. These fish tend to be raised in confined spaces that can lead to disease and pollution. Because conditions are cramped, they may get less exercise, which makes them a less healthy fish. Farmed salmon, for example, can develop up to three times more saturated fat than wild salmon, caused partly by too little exercise and manmade fish feed. They may be more prone to greater accumulation of toxins, including polychlorinated biphenyls (PCBs). Farmed fish can also contribute to the depletion of wild fish through feed. In her book "How to Be a Conscious Eater," Sophie Egan writes that producing fish feed is extremely inefficient: "It takes more than 15 pounds of wild fish to produce 1 pound of farmed tuna. This practice ravages stocks of certain 'forage fish' (anchovies, herring, menhaden) to make fish meal and fish oil to feed the fish whose wild stocks you're supposedly offsetting by enhancing the total supply." Furthermore, there have been escapes of farmed fish into natural environments that threaten the health and stability of wild fish populations. In 2018, more than 300,000 farmed Atlantic salmon escaped from an enclosure off the Washington coast and disappeared into a habitat dominated by Pacific salmon. The long-term effects are unknown, raising questions about the wisdom of farming a species of fish so far from its natural habitat. "I" is for Investigate Dig into the sources of your seafood and ask where it's from. There are lots of tools to do so. Look for reliable certification labels such as the Monterey Bay Aquarium, which runs the highly respected Seafood Watch program (download a handy reference sheet here or get the app for your phone) or the Marine Stewardship Council's blue label on packaging. Check out the Environmental Working Group's Consumer Guide to Seafood or the Environmental Defense Fund's Seafood Selector that includes a sushi-specific guide. The Aquaculture Stewardship Council's ratings are specific to farmed fish and adhere to fairly strict standards. "S" is for Small The smaller the fish, the better it is for a number of reasons. These tend to be the healthiest, as they're rich in omega-3 fatty acids, which is a big part of why eating seafood is healthy in the first place. They contain fewer toxins, such as mercury, because they are low on the food chain and the chemicals have not been able to bio-accumulate. An article on Oceana's blog points out that harvesting smaller fish uses much less fuel, making it a lower carbon option. Amy McDermott wrote, "Fisheries targeting anchovy, mackerel and similar fish are the most fuel efficient, according to a 2015 study coauthored by [Peter] Tyedmers [who studies the environmental consequences of food systems at Dalhousie University in Halifax]. They average less than 80 liters [21 gallons] of fuel per ton of catch when fishermen use purse-like nets to surround huge schools of the fish. Because these species swim in dense aggregations, fishermen can locate a swarm, throw a net around the whole thing, and pull up thousands of fish in one trip." This is not part of Selengut's rules, but "S" could also stand as a reminder to avoid shrimp. It's the most popular seafood in the US, but arguably the most damaging because of the way it's caught – using trawlers that drag along the ocean bed, scooping everything in their path. Dr. Ayana Elizabeth Johnson, marine biologist and founder of the Urban Ocean Lab, writes on her website: "To paraphrase Sylvia Earle, the terrestrial equivalent of bottom trawling would be using a bulldozer to catch songbirds. Farming shrimp also results in massive amounts of habitat destruction – mangrove forests off the coast of countries in southeast Asia in particular." Side note: While we're on the topic of seafood to avoid, octopus is another species that's best avoided. They are such clever, interactive animals, but their wild fishery is in decline and farming them is highly complicated, leading to large numbers of deaths from stress. Do yourself a favor and watch "My Octopus Teacher" on Netflix. You'll never want to eat another one again. "H" is for Home Buy fish that has traveled the least distance to your plate – same as everything else, ideally! If you live in the U.S. or Canada, you can trust the governmental bodies overseeing fisheries to do a reliable job of managing fish stocks. Dr. Johnson explains that the US adheres to the Magnuson Stevens Act (MSA): "Just 18% of the fish stocks managed under the MSA are considered overfished compared to about 34% of fish stocks globally. U.S. fishing vessels are also subject to a number of labor requirements while labor conditions on some international fishing boats can be quite poor." Imports from overseas are less transparent and harder to trace, and recent investigative reports have uncovered the horrifying use of slave labor on Thai shrimp boats. It's safest to buy American, and this also keeps profits closer to home, benefiting local fishermen. This article was updated with additional sourcing. View Article Sources Jacquet, Jennifer et al. "Seafood In The Future: Bivalves Are Better". Solutions, vol 8, no. 1, 2017, pp. 27-32. Aubin, J. et al. "Assessment Of The Environmental Impact Of Carnivorous Finfish Production Systems Using Life Cycle Assessment". Science Direct, 2009. "Factory Fish Farming". Food & Water Watch, 2013. Palstra, Arjan P., and Josep V. Planas. "Fish Under Exercise". Fish Physiology And Biochemistry, vol 37, no. 2, 2011, pp. 259-272. Springer Science And Business Media LLC, doi:10.1007/s10695-011-9505-0. Leech, Joe. "Wild Vs Farmed Salmon: Which Type Of Salmon Is Healthier?". Healthline, 2018. McDermott, Amy. "Eating Seafood Can Reduce Your Carbon Footprint, But Some Fish Are Better Than Others". Oceana, 2018. McKie, Robin. "Octopus Farming Is ‘Unethical And A Threat To The Food Chain’". The Guardian, 2019.