by Elizabeth Kolbert
The Atlantic bluefin tuna is shaped like a child’s idea of a fish, with a pointy snout, two dorsal fins, and a rounded belly that gradually tapers toward the back. It is gunmetal blue on top, and silvery on the underside, and its tail looks like a sickle. The Atlantic bluefin is one of the fastest swimmers in the sea, reaching speeds of fifty-five miles an hour. This is an achievement that scientists have sought to understand but have never quite mastered; a robo-tuna, built by a team of engineers at M.I.T., was unable to outswim a real one. (The word “tuna” is derived from the Greek thuno, meaning “to rush.”) Atlantic bluefins are voracious carnivores—they feed on squid, crustaceans, and other fish—and can grow to be fifteen feet long.
At one time, Atlantic bluefins were common from the coast of Maine to the Black Sea, and from Norway to Brazil. In the Mediterranean, they have been prized for millennia—in an ode from the second century, the poet Oppian describes the Romans catching bluefins in “nets arranged like a city”—but they are unusually bloody fish, and in most of the rest of the world there was little market for them. (Among English speakers, they were long known as “horse mackerel.”) As recently as the late nineteen-sixties, bluefin in the United States sold for only a few pennies a pound, if there were any buyers, and frequently ended up being ground into cat food. Then, in the nineteen-seventies, the Japanese developed a taste for sushi made with bluefin, or hon-maguro. This new preference, it’s been hypothesized, arose from their exposure, following the Second World War, to American-style fatty foods. The taste for hon-maguro was, in turn, imported back to the U.S. Soon, fishing for bluefin became so lucrative that the sale of a single animal could feed a family for a year. (Earlier this year, a five-hundred-pound Pacific bluefin went for an astonishing three hundred and forty dollars a pound at a Tokyo fish auction.) First, the big bluefins were fished out, then the smaller ones, too, became hard to find. Tuna “ranching,” a practice by which the fish are herded into huge circular nets and fattened up before slaughter, was for a time seen as a solution until it was shown to be part of the problem: as fewer bluefins were allowed to reach spawning age, there were fewer and fewer new fish to fatten.
Bluefin catches are managed—the word is used here loosely—by the International Commission for the Conservation of Atlantic Tunas. The commission, known by the acronym ICCAT—pronounced “eye-cat”—is based in Madrid, and its members include the U.S., the European Union, Japan, Canada, and Brazil. In 2008, ICCAT scientists recommended that the bluefin catch in the eastern Atlantic and the Mediterranean be limited to between eighty-five hundred and fifteen thousand tons. ICCAT instead adopted a quota of twenty-two thousand tons. That same year, a panel of independent reviewers, hired by the commission to assess its performance, observed that ICCAT “is widely regarded as an international disgrace.” (Carl Safina, the noted marine conservationist, has nicknamed the group the International Conspiracy to Catch All the Tunas.) By most estimates, bluefin stocks have fallen by eighty per cent in the past forty years. According to other assessments, the situation is even grimmer. Callum Roberts, a professor of marine conservation at England’s University of York, has calculated that there is now only one bluefin left for every fifty that were swimming in the Atlantic in 1940.