Science: Aquaculture: Food from the Deep

IN the past 100 years, the amount of food taken from the sea has multiplied more than tenfold, a rate in excess of global population growth. But the annual world catch—now about 60 million metric tons—cannot continue growing indefinitely. In fact, such sea staples as California sardines, Northwest Pacific salmon and Barents Sea cod —not to mention the beleaguered whale —are already rapidly dwindling. Contrary to the myth, Fisheries Biologist William Ricker recently warned, in a National Academy of Sciences report, the sea is not "a limitless reservoir of food energy."

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