The Fate of the Ocean
Page 7 of 12
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Hixon tells me that we need a Kuhnian paradigm shift in fisheries management. “Current managers learned single-species management, and they’re resistant to changing that, even though it seldom works.” A scientific consensus signed by him and 218 other scientists and policy experts pleads for an updated approach: “From a scientific perspective, we now know enough to improve dramatically the conservation and management of marine systems through the implementation of ecosystem-based approaches.”
As on land, protecting places is the best way to preserve life. In 2003, the World Conservation Union listed 102,102 protected areas on earth. But only 4,116 of these were protected marine areas, preserving less than 0.5 percent of the world ocean, whereas 11.5 percent of the land surface has been granted some form of sanctuary. To reach parity, we need to add 23 times as many marine reserves and offshore national parks, or 10 times more total area—and perhaps even more, since the liquid medium of the ocean is more in-terconnected, and the fate of its disparate realms more intertwined than here.
RACHEL CARSON wrote of the sea that “in its mysterious past it encompasses all the dim origins of life and receives in the end, after, it may be, many transmutations, the dead husks of that same life. For all at last return to the sea—to Oceanus, the ocean river.” We return to the sea, too, in various husks, including in the form of atmospheric emissions. Sweden, for example, calculates that its populace of 8.9 million carries 2.8 tons of mercury fillings in their mouths, most of which is destined eventually to go airborne in crematoriums.
Crematory emissions are a small but growing percentage of the total global mercury pollution, the vast majority of which enters the foodweb as a biologically active derivative of the inorganic mercury released by the smokestacks of the coal and chlorine industries. Oxidized in the atmosphere and piggybacking on raindrops, this form of mercury eventually settles to the bottom of oceans and lakes, where it is converted to dangerous methylmercury by aquatic bacteria, which are eaten by plankton, which are eaten by fish, and bigger fish—with each subsequent meal bioaccumulating in higher levels until apex predators such as tuna and whales carry mercury levels as much as 1 million times higher than the waters around them.
As do we. Epidemiological studies show that mercury levels among Arctic peoples are high enough to cause neurobehavioral effects, while a Hong Kong study revealed that 10 percent of the region’s high school students suffer mercury poisoning from eating tuna and swordfish. The European Union warns pregnant women to limit their consumption of both tuna and swordfish because of brain damage to their unborn children, and the U.S. Food and Drug Administration warns pregnant women, lactating women, and young children not to eat swordfish, shark, tilefish, or king mackerel, though the powerful tuna lobby succeeded in keeping tuna off that list. The EPA now estimates at least one in eight American women of childbearing age has unsafe levels of mercury in her blood, and as many as 600,000 of the 4 million babies born in the United States in 2000 were exposed to unacceptable levels because their mothers ate a diet rich in fish (in a continuation of bioaccumulation, the level of mercury in a fetus’ blood can be 70 percent higher than its mother’s). Yet the Bush administration, circumventing the Clean Air Act, has enabled coal-fired power plants to delay curtailing significant mercury emissions until 2018.
IT’S MIDNIGHT OVER THE GULF OF MEXICO, the skies stripped of clouds and glittering with stars as 25-knot winds blow down from the north. For most of the residents of the bayou country of southern Louisiana, these are welcome winds; only a month has passed since Hurricane Katrina made landfall, and 11 days since Hurricane Rita, and these northerlies are cold and dry enough to dismantle any additional tropical storms from the top down. It’s also blowing sufficiently hard that Captain Craig LeBoeuf decides to sail R/V Pelican through the Intracoastal Waterway and out into the Gulf at Morgan City, so that dawn will light our way along the shallow shelf where more than 100 hurricane-broken oil rigs and drilling structures foul the waters.
This once was one of the most prolific bodies of water on earth, a place where the outflow from the Mississippi River introduced freshwater nutrients into a deepwater environment. But long before Katrina, the Gulf had become one of the world’s most polluted marine ecosystems, with mercury loads among the highest ever recorded, including levels in blue marlin 30 times above what the EPA deems safe for human consumption. An average of 10 tons of mercury comes down the Mississippi every year, with close to another ton added by the offshore drilling industry. Equally alarming, a sizable portion of the Gulf is so biologically dysfunctional on a seasonal basis that it’s known as a dead zone—the largest such area in the United States and the second largest on the planet, measuring nearly 8,000 square miles in 2001, an area larger than New Jersey.
