For conscientious consumers, ordering fish in a restaurant can be an exercise in frustration: Which fish are endangered? Which adjectives are meaningful?

Where did I put my Monterey Bay Aquarium Seafood Watch pocket guide?

The responsible consumption of seafood is so complicated by overfished waters, mislabeled products, environmental threats—and shifting statuses of all of these—we devoted our February cover to the restaurants that source their fish most sustainably. (And prepare them most delectably.)

Now comes more help still, from the folks at the international ocean conservation group, Oceana. When faced with a menu full of seafood choices, they advise, all you have to remember are four words:

Wild. “Organic,” when applied to seafood, is a meaningless designation in the United States. Look instead for the term “wild,” which mean fish that are more sustainable and can have twice the omega-3s and half the fat of farmed fish.

Local. By “local” Oceana means “United States,” which they maintain has some of the best-regulated wild fisheries in the world. But here in the Northwest you can go hyperlocal, increasing freshness and decreasing carbon footprints by aiming for fish plucked from our own waters.

Little. In some quarters, little fish like sardines and anchovies don’t have the culinary cachet of tuna, halibut, or salmon. They do, however, have eco-cachet. Eating lower on the food chain is more sustainable for the ocean’s ecosystem and doesn’t require environmentally destructive deep-sea trawling.

Shellfish. The hardest-working environmentalists of the sea, shellfish filter and clean water by feeding on phytoplankton. Says Oceana: “One ton of harvested oyster meat offsets the equivalent of the waste contribution of thirty-eight people per year.” Oyster happy hour, here we come.

Finally, Oceana dispenses a shot of common sense: You don't have to be perfect. "Too often, the teenager working the summer job behind your local fish counter or as a server at your favorite seafood restaurant may not know whether the filet of 'cod' you want to eat was caught off the coast of Iceland with a hook and line, or on Georges Bank with bottom trawl gear." Or is, in fact, not cod at all. 

Just do your best to remember wild, local, little, and shellfish and you'll make a difference.