I”ve heard that a number of fish commonly available in seafood

I”ve heard that a number of fish commonly available in seafood restaurants are now threatened with extinction. Is this true?

—Glenn Hammond, San Francisco, CA

No doubt the age of commercial/industrial fishing, which dawned in the 1950s when large offshore trawlers and at-sea processing facilities first plied the open ocean, has taken its toll on a number of fish species. Atlantic Cod, for example, once teemed off the coast of New England and sustained millions of settlers and then immigrants. But populations have been reduced by more than 90 percent in the last half century, and diners would be hard-pressed to find any for sale at restaurants or fish markets these days.

Ocean activists have been working hard to prevent another tragedy on the scale of the Atlantic Cod, though several other endangered fish species are still widely available throughout the U.S. and elsewhere. Examples include shark, red snapper, bluefin tuna, wild shrimp, wild caviar and orange roughy. Over-fishing, the illegal trade, habitat loss and pollution have put these and many other marine species at risk.

On the bright side, some threatened populations are now on the reboun! d, thanks to efforts to reduce consumption. Chilean Sea Bass, for example, was all the rage at gourmet eateries in the 1990s. But in just two decades, the average size of individual fish caught dropped by more than 60 percent, meaning that fishermen were taking all the adults, thus decimating their reproductive capacity. By getting hundreds of restaurants to stop serving the trendy fish, a coalition called the Seafood Choices Alliance (SCA) was able to significantly reduce the strain on the species. Similar campaigns are underway now to try to bring the Atlantic swordfish, shark and bluefin tuna back from the brink.

SCA also works to educate seafood wholesalers, chefs and consumers about which types of fish consumers can indulge in guilt-free. SCA lists 19 species on its SeaSense Safe List for 2005, including abalone, Dungeness crab, northern pink shrimp, oysters and sablefish. The organization also produces the “Sourcing Seafood” handbook to help seafood buyers navigate the murky waters of purchasing sustainably harvested seafood.

Meanwhile, the Monterey Bay Aquarium”s website features Seafood Watch, a free series of guides to help consumers figure out which types of fish are OK to eat. And the company EcoFish sells a wide range of sustainably harvested seafood products to more than 1,000 grocery and natural food stores and to over 150 restaurants nationwide. Consumers can buy EcoFish products directly via the company”s website.

But eater beware: Even if the fish on your plate is not threatened with extinction, it might contain traces of mercury, the heavy metal which is emitted from coal-burning power plants and has been found to cause a wide variety of human health problems. As a result of the threat, the U.S. Environmental Protection Agency (EPA), while acknowledging that fish provide one of the healthiest sources of protein in our diets, recommends that pregnant women, nursing mothers and young children limit their intake to two meals pe! r week of seafood such as shrimp, canned light tuna, salmon, pollock and catfish.

CONTACTS: Seafood Choices Alliance, “www.seafoodchoices.org; Monterey Bay Aquarium Seafood Watch, www.montereybayaquarium.com/cr/seafoodwatch.asp, EcoFi

sh, www.ecofish.com, U.S. Environmental Protection Agency (EPA), www.epa.gov