One of the impacted corals with attached brittle starfish. Although the orange tips on some branches of the coral is the color of living tissue, it is unlikely that any living tissue remains on this animal. Lophelia II 2010; NOAA OER and BOEMRE

By Sandy Bauers, Inquirer Staff Writer
20 April 2012 The scientists were a little tired and burned out. For two weeks, they had been aboard a research ship in the Gulf of Mexico, trying to find and analyze deep-sea communities of coral on the dark bottom, nearly a mile below. A robot submersible was down there now. Charles Fisher, a Penn State biologist who specializes in corals, was doing other work as he kept an eye on the video feed. Suddenly, he stopped. They had found the reef they were searching for. And it didn’t look good. Something was wrong. Two years after the April 20 explosion on the Deepwater Horizon drilling platform and a three-month gusher that released five million barrels of oil into the Gulf of Mexico, the laborious and meticulous process of quantifying the damage is still under way. Much of the research by the government remains confidential because it may ultimately be part of legal proceedings against BP, the company that owned the rig. But some results are being made public, including the recent findings of several Pennsylvania scientists studying deep-sea corals. Last month, coral experts from Temple University and Pennsylvania State University, plus a geochemist from Haverford College, published a paper in the Proceedings of the National Academy of Sciences, showing that coral colonies at a site seven miles from the well – and in the path of the drifting oil – suffered severe effects. The corals showed “widespread signs of stress,” according to the paper. Of 43 kinds of coral, a quarter of them showed impacts to more than 90 percent of the colony. They were covered with brown goo. They had lost tissue. To Eric Cordes, a Temple University biologist who also was on the ship, it indicated “an ongoing process of death.” When the scientists got coral samples on deck, “we could see that everywhere they had been covered, the tissue was either gone or completely degraded.” For Fisher, “this is exactly what we had been on the lookout for during all dives, but hoping not to see anywhere.” It stood to reason the brown goo was petroleum, but for proof, the scientists turned to Haverford’s Helen White. She, like the others, eventually climbed into a submersible and traveled an hour to the seafloor to have a look and obtain samples. In the lab, she was able to fingerprint the substance and determine that it was oil and was from the spill. “It really underscores how unprecedented this spill was in terms of its size,” White said. Most spills are on the surface. This one happened at depth. “It really shows this spill had the ability to impact more than a typical surface slick.” […]

2 years after spill, troubling signs for life on seafloor