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For more information on these science news and feature story tips, contact the public information officer listed at (703) 292-8070. Editor: Josh Chamot Contents of this News Tip:
Galápagos Iguana Deaths Reveal Surprising Damage From Low-Level Oil SpillsThe ecological effects of low-level oil spills may be more serious than previously thought, according to a study documenting the widespread death of marine iguanas on a Galápagos island. In research funded by the National Science Foundation (NSF), Princeton University biologist Martin Wikelski and colleagues reported that more than half the marine iguanas on the Galápagos island of Santa Fe died with a year after a grounded tanker dumped nearly 800,000 gallons of oil into nearby waters. The consequences of the spill had been thought to be relatively mild, because strong currents dispersed the oil. In the immediate aftermath, it seemed that the lives of all but a few marine animals were spared. However, the researchers' findings suggest that many iguanas died because oil killed off a beneficial microorganism that lives in the animals' guts and helps them digest their diet of seaweed. Iguana populations on other Galápagos islands that were not affected by the spill did not suffer declines during the same period. "Our results illustrate the severe effects that low-level environmental contamination can have on wild animal populations," Wikelski and colleagues wrote, adding that the findings are a warning against complacency over apparently "low-impact" contamination. Wikelski's research confirmed a dire prediction he had made based on results of his earlier work with the iguanas. In an ongoing study, Wikelski and colleagues have shown that iguanas that died because of famine had increased blood levels of the stress hormone corticosterone in the weeks before death. By coincidence, the researchers had tested the corticosterone levels in the iguanas just three days before the tanker Jessica ran aground on San Cristóbal Island Jan. 17, 2001. They returned after the accident and found that the levels had increased dramatically, leading Wikelski to predict that many iguanas would die. "In this context, corticosterone levels are a reliable indicator of the induction of life-threatening stress," he said. This simple blood test could be valuable to biologists who need to estimate the severity of environmental disasters well before the animals start to die, Wikelski said. [Cheryl Dybas] "Rosebud" Replaces "Rose Garden" on Galápagos SeafloorScientists believe that the "Rose Garden" in the Galápagos Islands - one of the first hydrothermal vent communities discovered - may have been "paved over" by a recent volcanic eruption. However, scientists on a recent expedition to the site also discovered a thriving new community of very young tubeworms, clams, and mussels nearby which they have dubbed "Rosebud." The 12-day expedition to the Galápagos Rift, funded by NSF, the National Oceanic and Atmospheric Administration's Ocean Exploration Program, and the Woods Hole Oceanographic Institution, explored the same sites where hydrothermal vents were first discovered 25 years ago. First seen by researchers in 1979, the Rose Garden site was found to have red-tipped tubeworms peeking out of six-foot-tall white tubes that swayed in shimmering warm vent fluids. Scientists had revisited the site, an icon for deep-sea biologists, in the 1980s and 1990s and observed how mussels and clams had begun to overrun the tubeworm population. The researchers had hoped the recent expedition, which began on May 24, would extend this longest-running investigation of how vent communities evolve over time. But the expedition found no signs of Rose Garden. Instead, scientists found a field of fresh lava and a new community of very young clams, mussels and tubeworms as small as one inch tall. "The new Rosebud site could be very young - less than a year old," said Tim Shank, a biologist at Woods Hole. "We may have lost Rose Garden, but we have found Rosebud. It is a brand new site, perhaps very near its inception, whose evolution we can chronicle in the future." Scientists also discovered a new, shallower hydrothermal vent located some 200 miles (322 km) west of the historic Galápagos Rift vent site. The seafloor community is brimming with large clams and mussels up to 10 inches (25 cm) across. [Cheryl Dybas] Scientists Find Evidence of Cataclysmic Volcanic Event on OahuDuring a recent Ocean Drilling Program (ODP) expedition known as Leg 200, researchers found new evidence for a cataclysmic volcanic event two million years ago on the Hawaiian Islands. The volcanic discovery was an unexpected bonus for mission scientists who set out last December to drill a hole in the sea floor to house a deep-sea geophysical, geochemical and microbiological observatory. NSF is the principal funding source for ODP. "Hotspot" volcanoes, such as the Hawaiian and Canary Islands, are so steep that large segments often collapse to the ocean floor in huge landslides. Two million years ago, the Nuuanu landslide removed half of the island of Oahu. While drilling Nuuanu deposits in the Pacific Ocean 300km northeast of Oahu, ODP scientists encountered two layers that were originally deposited at temperatures exceeding 200 C (392 F). "Our results indicate that this event was not merely a landslide, but a hot explosion. The same process could happen again to the Big Island," said Leg 200 co-chief scientist Ralph Stephen of the Woods Hole Oceanographic Institution. Stephen led the expedition along with co-chief scientist Junzo Kasahara of the Earthquake Research Institute, University of Tokyo. According to Stephen, the large landslide was associated with an explosive event more than ten times larger than the 1980 Mount Saint Helens eruption in Washington State. Under normal conditions, the magma under a volcano is held in place by the weight of the overlying rock. When a large landslide removes the rock, the hot magma explodes into the surrounding air and sea. Drilling on Leg 200 gave the first evidence that the Nuuanu landslide could have been associated with such a violent and hot event. [Cheryl Dybas] Federal Support for Science and Engineering Increasing, Report ConcludesAccording to a recent NSF report, federal support for academic science and engineering increased by 10 percent between 1999 and 2000. Four-fifths of the increase came from the Department of Health and Human Services, which accounted for three-fifths of the $19.9 billion total. The data is contained in the report Federal Science and Engineering Support to Universities, Colleges and Nonprofit Institutions: Fiscal Year 2000. Produced by NSF's Division of Science Resources Statistics, the report also detailed information on federal support in colleges and universities across the country. Of the 100 universities and colleges receiving the most federal funds, Johns Hopkins University, which received $933 million in federal support, continues to top the list. Four of the top 10 universities were in California: the University of California at Los Angeles was third; Stanford, fourth; the University of California at San Diego, seventh; and the University of California, San Francisco, tenth. Other universities in the top ten were the University of Washington, second; the University of Michigan, fifth; the University of Pennsylvania, sixth; Harvard University, eighth; and the University of Colorado, ninth. Support for research and development projects accounts for about 85 percent of the science and engineering total. Universities also receive federal support for fellowships, traineeships, training grants, facilities and other activities. [Bill Harms] For more information, see: http://www.nsf.gov/sbe/srs/nsf02319/start.htm.
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