You cannot pick up a health-oriented magazine these days without finding an article touting the benefits of eating fish. Usually the articles identify a handful of fish as the best choices for adding omega-3’s into a diet through weekly consumption or explain a regime of fish oil supplements. While some experts have recently started warning about the dangers of mercury in exposure from consuming too much of certain fish, most do not discuss the general environmental impacts of their recommendations. However, the fish you choose impacts not only your health, but also the health of the U.S. fisheries; to make wise choices consumers need to consider what threatens the fisheries from which their fish was harvested.
The fishing industry has survived for the past few decades on dwindling profit margins that have driven many to adopt unsustainable fishing practices. Some commercial fishing enterprises feel compelled to adopt poor fishing practices to increase their catch from these dwindling populations. Others adopt damaging practices to increase their productivity to stay profitable as fish prices fall. Regardless of the reasons for using these practices, the damage done to the marine ecology cannot be dismissed. The two most serious threats from commercial fishing are overfishing and poor fishing practices.
Overfishing occurs when fishermen harvest more of a commercial fish population than can be replaced during the spawning season or when by-catch levels hurt a non-commercial marine animal population. The National Marine Fishery Service classifies one third of the assessed U.S. fish stocks as over-fished, including several commercially important stocks. Unfortunately, the regional councils that set harvest levels for these populations routinely set levels above what scientist identify as sustainable. Bycatch, the capture of one species while fishing for another, also makes it difficult to prevent overfishing in some fisheries and to rebuild others. For example, for every pound of Gulf of Mexico shrimp landed fishermen discard over four pounds of other dead or dying finfish, such as juvenile red snapper (an already over-fished commercial stock).
Poor fishing practices can subject vast areas of the seafloor to damage from actions like bottom trawling and dredging, which degrades or destroys important fish habitat. When trawling boats attach weights to the bottom of the nets and then drag them for miles along the seafloor leveling everything in its path. The destruction of the bottom habitat entangle the shellfish and other bottom resting fish in the net as they try to flee the destruction of their homes. Not only does this method produce significant by-catch, it destroys coral reefs and seaweed beds. People occasionally compare this activity to clear-cutting a forest, but in some ways, trawling is more damaging than clear cutting. Many coral beds damaged by this practice are centuries old and their slow rate of growth make them impossible to replace. Scientist have found that some areas trawled fail to restore even basic ecological systems within five years of being destroyed. Some fishermen certify the use of safe harvesting methods and I recommend purchasing from these sources when they are available, but this certification is relatively new and cannot be found in all stores.
Non-fishing threats to important fish habitat also abound. Builders dredge, fill and destroy salt marshes. Dams block salmon runs. Healthy fish stocks cannot be maintained without the habitat necessary for spawning, shelter, and feeding. Water pollution from human activities has spread throughout the hydrological ecosystems allowing longer-lived and fatty fish to accumulate significant levels of toxins and heavy metals.
The accumulation of toxins in fatty fish prove particularly frightening, because those a generally the fish most recommended by the medical community. Fatty fish provide one of the healthiest fats because they are high in EPA and DHA. These omega-3 fatty acids contribute to a healthy heart and brain. Doctors recommend taking fish oil supplements or eating more fatty fish to help patients manage a variety of healthy conditions from depression to high cholesterol. Unfortunately, in recent years people who add fish to their diet without an awareness of the health of the fish they consumed have experience side effects from the toxins in the fish. In fact the documentation of people suffering from the accumulation of mercury in tuna forced the Environmental Protection Agency to issue consumption advisories the strictly limited the amounts that pregnant women and children could consume.
Various environmental groups focused on protecting fisheries have developed list of recommended fish by either identifying fish that commonly come from sustainable fisheries or identifying fish that generally do not accumulate high levels of toxins. Medical sources have list of recommended fish based on potential health benefits. In the list below, I have combined some of the more popular list to identify the fish choices that are healthiest for you and the environment.
Good Fish Guide
Low in Mercury & High in Omega-3s
Crab (Dunegess, Snow, and Stone)
Rainbow Trout (farmed)
Salmon (wild Pacific)
Low in Mercury & Moderate/Low Levels of Omega-3s
Mussels (farmed) Oysters (farmed)
Sturgeon (US farmed)
Tilapia Catfish (high in POPs)
Once a month consumption due to toxins or questionable fishing practices
Crab (Blue, imitation and King)
salmon (Atlantic or farmed)(toxins)
Shrimp (farmed domestic)(toxins)
Tuna, mixed (toxins)
Avoid because of mercury or unsustainable fishing practices
Caviar (imported or wild)(PFM)
Chilean Seabass (PFM & PFP)
Crab (King- imported) (PFM)
King mackerel (PFM)
Largemouth bass (PFM)
Monkfish (PFM & PFP) Orange Roughy (PFM)
Rock Fish (PFM & PFP)
Shrimp (Gulf and imported) (PFP)
Tuna,albacore (steaks or canned)(PFM & PFP)(mercury)
White croaker (PFP)
‘PFM’ – poor fishery management; ‘PFP’ – poor fishing practices. Resources for information were Environmental Working Group, Monterey Bay Aquarium, Institute for Agriculture and Trade Policy, the Pacific Whale Foundation, the Omega-3 Information Service and the FDA.