On Monday, Whole Foods Market Inc. unveiled a new initiative: seafood ratings based on environmental friendliness. This move toward sustainability is part of a national trend, the Associated Press reports, that is also reflected in the pledge of fellow retailer Trader Joe's to carry only sustainable seafood by 2012 and Target Co.'s move to stop selling farmed salmon. (See also Corby's recent piece about how McDonald's, Long John Silver's, and Red Lobster are embracing sustainable fish.) As part of this broader, consumer-driven movement, Whole Foods's new rating system relies on the red, yellow, and green colors of traffic lights, similar to the U.K. "traffic light" health labels—recently done away with—that Marion Nestle wrote about on the Atlantic Food Channel:

The program is the latest in a series of moves by major grocers to change seafood policies as concern rises about overfishing and the environmental effects of certain fishing methods.

Similar to a stoplight, seafood is given a green, yellow or red rating. A green rating indicates the species is relatively abundant and is caught in environmentally friendly ways. Yellow means some concerns exist with the species' status or the methods by which it was caught. And a red rating means the species is suffering from overfishing, or the methods used to catch it harm other marine life or habitats.

The company, based in Austin, Texas, said it is the first national retailer to display such ratings.

Read the full story at the Associated Press.