Our Imperiled Oceans: Victory at Sea- page 3 | Science | Smithsonian
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The waters around the Phoenix Islands Protected Area (yellow and blueback fusiliers) hold some of the world's most pristine coral reefs (Paul Nicklen / National Geographic Image Collection)

Our Imperiled Oceans: Victory at Sea

The world's largest protected area, established this year in the remote Pacific, points the way to restoring marine ecosystems

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(Continued from page 2)

It was clear that outlawing the small-scale commercial fishing that occurred close to the Phoenix Islands would pose no political problem, but restricting deep-ocean fishing could be painful: nearly a third of Kiribati's $80 million annual budget came from licenses sold to deep-water fishing operations, especially the large ships that can haul up to 100 tons of skipjack, yellowfin and bigeye tuna a day.

The key to banning tuna fishing was the Washington, D.C.-based environmental group Conservation International, which Stone brought into the negotiations. The group said it could raise money for the management of a marine reserve and compensate the I-Kiribati for any income they forfeited by restricting commercial fishing. "The Republic of Kiribati has now set a standard for other countries in the Pacific and elsewhere in the world," says Conservation International president Russell Mittermeier.

Kiribati President Anote Tong, a graduate of the London School of Economics, who was re-elected for his second four-year term this past October, has supported the reserve initiative from the beginning. "We thought it was a very good idea in this day and age of threat to biodiversity," he says in his spartan office in the ultramodern Parliament building. Tong, who favors traditional Pacific skirts, says "we believe the scope for eco-tourism is great."

Teroroko, whose salary as marine reserve director and budget come from Conservation International, says the reserve "gives us insurance against the loss of marine life. It will show the world that even though we're small, we are leaders. And it will give scientists a place to observe the impact of global warming with no other man-made factors present."

For a nation that is spread out across a series of coral atolls, the health of the surrounding reefs is a matter of life and death, for they provide not only food but also protection from waves. And such atoll reefs become even more important as sea levels rise. Seas rose almost 7 inches in the 20th century, according to the Intergovernmental Panel on Climate Change, and are conservatively predicted to rise between 8 and 24 inches this century because of melting of ice caps and other environmental changes brought on by global warming.

Healthy coral reefs will continue to grow even as sea levels rise, says Jim Maragos, a coral reef biologist with the U.S. Fish and Wildlife Service in Honolulu. "But the damaged ones will not." A dead or dying coral reef will break up into rubble after a couple of decades. Eventually, big ocean swells could wash away villages on islands that, like Tarawa, rise only a few feet above the high-tide mark.

As it happens, perhaps the most ambitious study of the health of coral reefs was conducted partly in Kiribati territory and reported this year. Scientists compared four areas of the Line Islands, strung across 450 miles: Kingman Reef, which has no permanently dry land, is a U.S. wildlife refuge; Palmyra Atoll has been closed to fishing since 2001; and the Kiribati islands of Tabuaeran (formerly called Fanning) and Kiritimati (formerly called Christmas), whose populations have shot up in the last few decades to 2,500 and 5,100, respectively. Both are now being overfished in parts, the scientists say.

"Going from Kingman to Palmyra to Fanning to Christmas is like going forward in time," says Sandin, of the Scripps Institution, who coordinated the study. "It gives you what we called a gradient of human disturbance—a way to examine precisely how human activity affects the reefs."

The marine scientists analyzed all aspects of reef life—fish, corals, algae and, for the first time, microbes. As they moved from Kingman to Kiritimati, the abundance of fish fell dramatically. At Kingman, it was 5.3 metric tons per hectare, of which 40 percent were sharks, 40 percent other large predators like jacks, snappers and groupers and 20 percent small fish. Palmyra came in at 2.5 tons per hectare, Tabuaeran at 1.7 tons and Kiritimati, where virtually all the sharks have been killed for their fins, at just 1.3 tons.

The scientists discovered a link between shark density and coral reef health: the coral reefs at Kiritimati had the most algal growth, and Kingman's the least. "We're not sure how the link works," says Sandin, "but we think that when there are large numbers of sharks, herbivores eat more algae and grow faster so they can reproduce before they themselves get eaten." Algae can stifle coral development and also release sugar into the water, providing food for bacteria that include pathogens like E. coli and streptococcus and staphylococcus, which increase the rate of coral disease and attack larvae of the organisms that make up coral reefs. Overall, the researchers found that the corals in Kingman were in much better shape than those in Kiritimati, despite satellite data indicating a 2002 spike in area water temperatures, which causes coral bleaching and other diseases. "This shows that healthy reefs with a lot of fish can survive global warming much better than fished-out ones," says Sandin. "That's another reason for creating more marine reserves and building up the fish populations."

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