Industry: Where Did the Menhaden Go?

The menhaden, a fish that can produce 700,000 eggs at the flip of a gill, was long one of the leading population exploders in the Atlantic Ocean and the Gulf of Mexico. Loaded with oil and bone, the eight-inch fish is about as welcome at a dining table as last Friday's halibut. Still, it is avidly sought by commercial fishermen because its oil is used in everything from lipstick to paint, and its meat and bones can be ground into high-protein animal feed.

In recent years, however, the menhaden has been in decline, and with it all of the largest...