As a pesco-vegetarian, I am acutely aware of how difficult making good fish choice proves. Information about how the specific fish you are considering in the market was caught or raised is usually not available. Often you must rely upon the average review of the practices for that species (and now that they do post locations the fishery).
Some fisheries and species information have great track records for being healthy and well managed, such as the wild Alaskan salmon fishery.
But other have shaky reviews and specific seasonal challenges that require the consumer to stay on the ball. For instance, even before hurricane season devastated the Gulf region with oil leaks and toxic runoff from damaged coastal areas, the coast experienced massive red algae blooms. Until recently red algae blooms were considered only a problem for the few weeks they lasted, but new research shows that fish exposed to red algae blooms carry the toxins for long periods after the bloom subsides. It maybe a year or two before I am comfortable eating fish from the Gulf for all these reasons combined.
I will not cut fish out of my diet, largely because 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 health oriented articles 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.
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 overfished, 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 overfished 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.
Non-fishing threats to important fish habitat also abound. Builders dredge, fill and destroy salt marshes; these marches serve as important hatcheries for many fish populations, as well as natural buffers for marine animals during storms. 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 are 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 sustainablely managed fisheries or identifying fish that generally do not accumulate high levels of toxins. I recommend checking out: the Monterey Bay Aquarium fish guide
(very detailed reviews of many commercial species); The Fish List
; Ocean Alive
; or Blue Ocean Institute
. I created my own list from these sources and from medical articles that identifies the environmental risk and the healthiest choices, which I will try to post as a Word document.
Good luck and shop smart.