As of 1995, some 37,000 industrial-sized fishing ships, plus about a million smaller boats, were between them taking twice as many fish from the sea as they had just twenty-five years earlier. Trawlers are sometimes now as big as cruise ships and haul behind them nets big enough to hold a dozen jumbo jets. Some even use spotter planes to locate shoals of fish from the air.
It is estimated that about a quarter of every fishing net hauled up contains "by-catch"—fish that can't be landed because they are too small or of the wrong type or caught in the wrong season. As one observer told the Economist: "We're still in the Dark Ages. We just drop a net down and see what comes up." Perhaps as much as twenty-two million metric tons of such unwanted fish are dumped back in the sea each year, mostly in the form of corpses. For every pound of shrimp harvested, about four pounds of fish and other marine creatures are destroyed.