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Page 1 | Page 2 | Page 3 | Page 4 Redefining Pristine Jen Smith, who has spent the last 8 years
studying Hawaiian reefs, returned from one of the dives to say, "My own
personal baseline was shifted yesterday." The shifted baseline is not
limited to things that we see with our eyes underwater, but also to
other benefits that the ocean shares with us. The food web phenomena ignited deeper questions within the Line Islands research group. If sharks and other predators are more prevalent in an unspoiled environment, perhaps this is the way things should be, rather than the much more common coral ecosystems characterized by few predators and abundant algae. This evoked the idea of "shifting baselines," the concept devised by fisheries biologist Daniel Pauly and popularized in large part by Scripps Professor Jeremy Jackson, also a Line Islands Expedition participant, that argues that environments appear "normal" to us as we first know them. In a personal sense a baseline could be a childhood memory of a favorite park or playground that is "shifted" when that place is degraded or "shifted" over time. Jackson's research shows that many well-grounded scientific ideas in marine ecology should be reevaluated because the baseline in which they were developed may have already been disturbed. Indeed, Sala says that more than 90 percent of marine biological studies, and 99.9 percent of studies on coral reefs, were conducted in conditions in which the environment was already seriously impaired. 
"There has been a shifting baseline in ecology because every ecosystem has lost its predators," said Sandin. "It's no longer accepted that that's the way things should work." In 2003, Palmyra Atoll was initially selected as the sole study site for the project because it had been regarded as a model destination for studying unspoiled coral reefs. With swaying palm trees and idyllic sunsets, it would be hard to argue otherwise at the surface. Yet underwater the researchers found a different scene. Thousands of U.S. soldiers were stationed at Palmyra during World War II because of the atoll's strategic location in the central Pacific Ocean. Even though the soldiers only stayed five years, they left a clear mark on the coral communities still visible today. The scientists were able to document areas of Palmyra that are clearly degraded and other areas that have rebounded in the decades since the war with the emergence of new coral growth "recruits." 
This evidence is giving them unique opportunities to study how much pollution and overfishing a coral system can withstand and what it takes to recover. They are making progress in dissecting the direct and indirect effects of each of these impacts. In the future, such analyses will be vital for decision makers around the world grappling with the best ways to implement marine reserves, locations set aside for rehabilitation from human impacts. "Learning about Palmyra and Kingman brings us back to square one," said Sala. "This will be important for science and for conservation. It will help us determine the minimum area that we need to protect if we really want to protect the entire ecosystem." Next page: 'This is getting into the unknown' |
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