It’s tough out there for a health-conscious, eco-minded carnivore. Many of the terrestrial sources of animal protein aren’t particularly healthful, thanks to how those animals are produced—factory farms, corn-rich diets, overuse of antibiotics. If you turn to the sea for protein, things aren’t exactly rosy. Numerous fisheries have been overfished for decades or even centuries, forcing well-intentioned seafood eaters to consult wallet cards or smartphone apps before they order cod, lobster, tuna, or vaguely-named snapper from a menu—and that’s assuming the menus are accurate, which often is not the case.
Aquaculture (“farming” finfish and shellfish) has a host of its own problems, ranging from the foul, fecal-rich effluent that seeps out of fish pens into the surrounding sea, to concerns over genetically modified organisms (GMOs) escaping their pens and interbreeding with wild populations, to diseases that thrive in and spread from densely-packed coastal fish farms. Meanwhile, those farmed fish must be fed, and the feed is often made of wild fish species, which means aquaculture may be maintaining overfishing as much as it’s alleviating it. “Closed” fish farms, such as the inland pens used to raise trout, tilapia, barramundi, catfish, and some of our farmed shrimp, don’t pose as many problems. The fish poop can be contained, GMO fish are unlikely to escape, and their diets can be soy based. But many of these products just don’t taste very good without heavy seasoning or a trip to the deep fryer, and in terms of the eco-friendliness of a given farmed fish, the devil is in the details. Some barramundi, for example, is to be avoided, and some is a “best choice,” according to Monterey Bay Aquarium’s Seafood Watch program. Whether you’ll be able to discern the good barramundi from the bad is up to the integrity of the supply chain and the honesty—or awareness—of the person serving you.
Meanwhile, lurking behind wild fisheries and farmed fish that depend on wild-caught fish for feed, is the problem of contaminants. Methylmercury, most of which originates in emissions from coal-fired power plants, is a toxin that accumulates in the flesh of aquatic animals. Because many fish are carnivores, the concentration of methylmercury increases as you look at each higher link in a marine food chain. Large predatory fishes such as tunas, sharks, and swordfish end up with some of the highest concentrations of methylmercury and other contaminants in their flesh. Westerners tend to favor those fishes because their steaks are boneless and firm and, well, most meat-like. The extent to which a tuna steak can be sanitized and beautified—treated with carbon monoxide to turn it a lip-gloss pink, vacuum sealed in plastic, and given the sexy Hawaiian name ahi—and the popularity of sushi have made Western consumers extremely fond of yellowfin, bluefin, and bigeye tuna, while the firm but milder albacore is the favorite for canning. All of these tunas carry significant concentrations of contaminants, even in the form of canned albacore, a.k.a. “chunk white.” The safest tuna product is canned “light” tuna, which is typically made of smaller species that don’t have as much methylmercury, such as skipjack. But even light tuna should be consumed just a few times a month, especially if you’re a growing child.
So, if the large wild fish species we favor are off the table because of overfishing and/or contamination, and farmed fish are contributing to other problems in our oceans, does it make any sense at all to eat fish and raise our children to be piscivores? One compromise is to switch from staples like canned tuna and farmed salmon to small, sustainable forage fish species such as sardines, anchovies, and herring. These fish are low enough on the food chain that contaminants are not a big threat. They are also, for the most part, considered sustainable, because they are short-lived and spawn at an early age—two characteristics that make a species less susceptible to overfishing.
But if we start eating sardines and other forage fish, won’t we just start overfishing them? That’s unlikely. We are already harvesting forage fish stocks quite intensively, but we do so largely to make feed for farmed fish or to capture things like lobsters, tunas, cod, and haddock via baited hooks and traps. In other words, we catch a lot of one thing just so we can catch or raise less of another—obviously not a very efficient way of getting protein. Instead of harvesting ten pounds of sardines in order to end up with one pound of tuna or salmon, we could just eat one pound of sardines and leave the other nine pounds out in sea to feed the wild populations of large, overfished species. In other words, switching from tuna to sardines will not only reduce the fishing pressure on tuna, but it could help keep populations of those larger fish well fed.
Okay, so how does one procure and prepare forage fish? There are many varieties of canned or jarred sardines, anchovies, and herring, from the low-end offerings from Bumblebee to high-end imports from Europe. At your local supermarket, you will find some of these products alongside the canned tuna and salmon, but others may be hidden in the import or “ethnic” aisles. Sardines canned in olive oil are an easy substitute for meat in pasta dishes, while lightly pickled anchovies or herring are tasty on their own or with crackers. If you can find fresh whole sardines, drizzle them with olive oil, salt, and pepper and throw them on a grill. The skin will crisp nicely, and you can use a fork to peel the fillets right off the backbone. (Any forage fish smaller than three or four inches will have bones that are so tiny and soft that you can just eat them. But if you really want your fillets to be boneless, you can find those too.) Canned sardines also make for great sandwiches.
Personally, even if health and sustainability were not concerns, I would choose a half-dozen grilled sardines over a seared tuna steak, or a tin of canned anchovies over a can of tuna, any day of the week. More tender, more flavorful.