Red fish, green fish

With bigger fish high in mercury content, and fish and other water-dwelling species of all kinds struggling for survival as a result of overfishing, anyone watching his or her health—or concerned about the environment—might be tempted to forgo fish altogether.

Unlike so many other food choices—organic versus non-organic, fresh versus processed—deciding which fish to select requires a lot of specific knowledge before determining if it’s one to choose or to avoid. This includes needing to know how a fish was raised, or where it was caught, and the survival status of a particular species which changes as fish populations diminish and rebound. Thankfully, there are a number of new tools to help us become better fish buyers.

Wallet cards—such as the free, downloadable one put out by Shedd Aquarium in Chicago (see column note)—are probably the best-known consumer tool for making ecologically sound fish choices, with smartphone apps a close second. Aimed at maintaining or restoring diminishing fish stocks, these little cards have lofty goals. Using simple color coding, wallet cards break choices into three categories:

• Green: Best choice. Fish stocks are abundant and well-managed; fish is caught or farmed in responsible ways.

• Yellow: Good alternative. There are concerns with how the fish is caught or farmed, or known habitat destruction.

• Red: Avoid. Biomass needs time to recover or changes are needed in how the fish is farmed or caught.

Of course, beyond this basic guide,there’s a lot to know about what’s happening to fish and why we should be concerned. There are five main factors that generally go into rating seafood:

• Overfishing: This happens when the biomass of a species becomes critically low or if a species is fished faster than it can reproduce to replenish stock. Haddock in the Northeast was for many years on the “avoid” (red) or “good alternative” (yellow) list depending on the catch method. Better management beginning in 1995 ended overfishing, allowing the species to recover. Choose hook-and-line-caught haddock (green) when possible.

• Bycatch: This is the unintended discarded dead or dying fish and other marine life. Fishers are allowed nine pounds of discard to every one pound of intended catch—a plainly unsustainable ratio. Ask about bycatch reduction equipment information, especially for shrimp. Pacific halibut fishermen adopted fly-fishing streamers and catch-shares to dramatically reduce the destruction of seabirds and turtles from their longlines, and to protect the fishery from overfishing. Look for wild-caught Alaskan halibut (green).

• Habitat destruction: This comes from destructive fishing methods such as bottom trawling—a practice that’s not unlike clear-cutting a forest to catch a few deer. Whole habitats are mowed down by large, heavy rolling bars paving the way for nets pulling up the ground-dwelling fish and everything else around it. Some trawlers have modified equipment to create less damage to the ocean floor.

The vast majority of imported shrimp is farmed in environmentally destructive conditions. All shrimp imported in the U.S. from Thailand is farmed. Only about 25 percent comes from recirculating systems that do not release untreated waste into the environment. Choose U.S. wild-caught shrimp if you can get information about bycatch reduction or imported Thai shrimp if it is from a recirculating farm.

• Aquaculture/farmed fish: At least half of the seafood we eat is aquaculture-raised. That is, farmed. And some fish farms use more fish (such as anchovies) for feed than they produce. Pressure is mounting for internationally recognized, environmentally sound aquaculture standards.

U.S. farmed catfish and barramundi are both good examples of environmentally sound aquaculture. The best farmed fish involves land-based, recirculating tanks and fish feed with a high portion of plant matter.

• Illegal, unreported and unregulated (IUU) fishing: Prior to 2010, IUU fishing accounted for 19 percent of world seafood catch, with an estimated worth of $13.5 billion. Some international discussions have begun to address improved traceability.

Bluefin tuna (“avoid”) is near collapse thanks to well-documented illegal fishing. Chilean seabass also comes from waters with high rates of illegal fishing. Avoid it altogether or choose only Marine Stewardship Council-certified Chilean seabass.

If you are nursing or pregnant, steer clear of large fish like tuna and swordfish, which have the highest quantities of pollutants like mercury and PCBs (polychlorinated biphenyls), substances that can impair neurological development in infants.

And sustainability can also include economic and social goals. Is the fishery from which your purchase comes managed in a way that sustains fish and local fishing communities? Many people choose to participate in community-supported fisheries programs to support their local economy and local families.

Before you head to the store or out to dinner, take a few minutes to familiarize yourself with the many tools now available. You’ll find that making healthful and informed seafood decisions is well within reach—as close as your phone or your wallet.

E/The Environmental Magazine