Yesterday, I went to a panel on sustainable fish hosted by chef Rick Moonen of RM Seafood in Las Vegas and the Environmental Defense Fund. We received a preview of Moonen's first-ever cookbook, Fish Without a Doubt (Houghton Mifflin)—challenging fish recipes with a sustainable bent—and learned some enlightening news from Moonen and the Environmental Defense Fund's experts:

—According to a 2006 study led by marine biologist Boris Worm, if nothing is done to protect our ocean's current fish stock, ALL the wild-caught fish we see in our supermarkets will be gone in 50 years.

—Most farmed salmon should be avoided, as it takes an average of three to six pounds of wild-caught fish to feed every pound of farm-raised salmon.

—Moonen advocates eating small fish on the bottom of the food chain, like anchovies and mackerel, since they're high in healthful omega-3 fatty acids and low in environmental contaminants.

—Canned tuna lovers should opt for "light" tuna, which tends to be lower in mercury than larger albacore "white" tuna.

—While Moonen shies away from advocating any one type of fish (he wants to avoid the kind of overfishing that happened after Julia Child called monkfish the poor man's lobster), he's currently hot on cobia, also known as lemonfish, a sustainably farmed fish from Belize.