All over the world, nearly-extinct sea creatures are caught and sold, and migrant workers are exploited for profit. As part of its sustainability efforts, Costco has long banned its stores from selling certain endangered fish.

In 2011, Costco removed Atlantic cod, Atlantic halibut, Chilean sea bass, Greenland halibut, grouper, monkfish, orange roughy, redfish, shark, skates, rays, swordfish, and bluefin tuna from its shelves. Every seafood item from the chain requires approval from the Marine Stewardship Council, which vets fisheries for environmentally sound practices.

In place of those no-go fish, Costco sells options like Sockeye salmon, which the Monterey Bay Aquarium Seafood Watch lists as a "certified buy." However, Sockeye are often wild-caught using Gillnets, which have been known to cause harm to sea turtles, but sockeye are still ultimately more sustainable than many other types of fish.