Glenn Jones, a paleoceanographer at Texas A&M University at Galveston, has been fishing through some 200,000 American menus to document how our appetite for seafood has changed the population of the world's oceans. Using menus from as far back as 1850, he noted the price of fish and shellfish meals and adjusted them for inflation. Jones found that for many species prices rose over time, suggesting that people's demand for seafood overwhelmed the ocean's supply.
In some cases, the increase has been modest: Raw oysters are only about twice as expensive as they were in 1850. Abalone, on the other hand, now costs about $70 a plate—10 times as much as when it first became popular in the 1920s—reflecting years of overharvesting so severe that the marine snails may never recover. Lobster prices soared in the 1880s and again in the 1950s as people's tastes changed. One after another, Jones says, popular wild fish have become so rare that they have vanished from menus, replaced by temporarily more abundant varieties. Halibut gave way to codfish, then haddock, and now scrod, which includes young haddock or codfish.
"Early on, people were harvesting these very large 300-pound halibut. Now they're down to juvenile fish," he says. "They're fishing their way through the food chain."