Reading my local newsweekly the other day, I was struck by a review of a sushi joint whose menu is focused on sustainable seafood. I've been hearing a lot lately about how our oceans are overfished, but this was the first time I'd seen a sushi restaurant engaging directly with the issue.
So, what makes for a sustainable sushi menu? And what can I as a consumer look out for the next time I'm at a seafood restaurant? To get some answers, I talked to Gretchen Helsel, who manages Tataki (the aforementioned sushi joint), and Casson Trenor, who works for the nonprofit FishWise and acts as a sort of fish consultant for the restaurant.
One red flag is farmed salmon. Tataki doesn't serve it because oftentimes the farms "are extremely dirty open-containment, or net-pen, farms where there's no barrier between the open ocean and farm," Trenor said. This was a problem I'd heard of: large concentrations of sewage from the captive fish pollutes the ocean; also, contagious diseases and parasites spread easily in a net pen and then infect wild fish.
Instead of farmed salmon, the restaurant offers wild Alaskan salmon and farmed Arctic char, which is better suited to farming, Helsel told me. "It's smaller, and it's better raised on vegetarian diet," she said.
Also absent from the menu are unsustainably farmed shrimp from Southeast Asia and unagi, or freshwater eel, whose wild populations are crashing, Trenor told me. "A huge proportion of unagi comes from China, and the industry is notoriously opaque" and plagued with problems such as escapism and disease. In place of unagi, Tataki serves anago, a wild saltwater eel.
Another item consumers might think twice about before ordering is bluefin tuna (toro, or fatty tuna, on menus). Why? Severe depletion, for one thing. "They're tasty and coveted, and because of that, they're disappearing faster than we could ever replace them," Trenor said. A bluefin farming industry has sprung up, he added, in which the fish are ranched—captured as juveniles and raised in a pen. "Every tuna you get out of a ranch would've been in wild and won't have a chance to breed." Another problem is that it requires an enormous amount of feed to produce a relatively small amount of bluefin; the protein ratio "approaches or exceeds 20 to 1," Trenor said. "It's inherently unsustainable."
Instead of bluefin, Tataki servesnet-caught skipjack and hand-line domestic yellowfin and albacore. Which points to another consideration for fish consumers: hand-line vs. long-line. "Hand-line means just using one hook and one line to catch one fish," said Helsel. "When they long-line, that's multiple hooks and lines that are miles long, and they leave them out there for days. By the time the boats go back out, there's a lot of bycatch—meaning turtles, birds, and so on that are dead."
Various seafood guides have been published to help consumers eat fish in a more sustainable way, but no one guide is sufficient for everyone, since where you live is a factor. Overfishing.org has a list of a number of guides, with links, here.