I went vegetarian-ish earlier this year, and I have eaten a lot of Filet 'O Fish sandwiches since then. (I call myself "vegetarian-ish" because I do eat seafood. And as you may have noticed, fish is not a vegetable.) I have had ample time to study the little cardboard box, with its printed message that "McDonalds Supports Sustainable Fishing." Conspicuously missing from the box is any information on what kind of fish is in that Fillet!