Authorities in coastal states from Maryland to Maine are warning consumers not to eat striped bass or large bluefish very often because they contain too much mercury. Pregnant women and children under age 6 are warned to avoid stripers or bluefish larger than 14 inches entirely, and everyone is being asked to limit consumption.
That's some serious stuff, as both species are major game fishes in the region and are widely eaten. Unfortunately both species collect so much mercury because they are high-ranking predators on the food chain, eating lots of smaller fish who each have far lower levels of the toxin. Mercury hangs around in an animal's system for a while, so your body needs a break between meals containing it in order to stay healthy. Fish-eating fishes don't get that break.
The silver lining is that bluefish are better eating at 14 inches and below -- the larger they get, the oilier and fishier they get. And large stripers over 36 inches are typically big breeding females, a group of fish we want to keep alive. Like bluefish, large stripers tend to have coarse meat that is not as fine as that from a smaller fish.
To read an overview on which fish and seafood are typically high in mercury, and which are safe to eat regularly, click here.