The Deepwater Horizon oil spill greatly affected coral populations

(new study) - A new study of two additional coral communities shows signs of damage from oil spills from the Deepwater Horizon oil spill in the Gulf of Mexico. This finding is by a group of scientists led by biochemist Charles Fisher of Penn State University.

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An article describing this study and the additional effects of human activity on coral communities in the Gulf of Mexico will be published this week in July, in the Yearbook's Early Edition online magazine. Proceedings of the National Academy of Sciences.

'The trail of oil spill impact on coral reef ecosystems is both deeper and wider than the data previously pointed out , ' Fisher said. 'This study clearly shows that diverse coral communities, stretching up to 22 km from the oil spill site and at a depth of more than 1800m, have been affected by the oil spill'.

Oil spilled from the oil spill in the Gulf of Mexico has almost melted, so other clues are now needed to determine if marine life is affected by spill. Fisher's team used the current environmental conditions in a coral community known to have been impacted by the spill in 2010 as a kind of 'fingerprinting' to measure the impact of oil spills in A coral community has been identified.

Unlike other organisms that have been affected by the spill that have vanished quickly from the sea floor, corals that form a mineral skeleton can survive for many years after corals die. 'One of the main reasons for coral's usefulness as an organism is that it is a coral skeleton that will hold evidence of long-term damage, after the damage caused by the oil ' , Fisher said.

Scientists compared the newly identified coral communities with a coral community that they discovered and studied over the period of the oil spill, using them as a reference model with the Growth of damage caused by oil spills over time.'We were able to identify evidence of oil spill damage in the two coral communities discovered in 2011, because we knew exactly the coral reef community affected by the spill in 2010 was How, it seems like we discovered new coral communities' at the time.

Corals rarely appear in the deep waters of the Gulf of Mexico, but because this species is an indicator organism to monitor the impact of environmental disasters such as the Deepwater Horizon explosion, efforts to find corals have been repay in useful scientific data. " We have been searching for coral reefs at depths of more than 1,000 meters and are often smaller than the size of a tennis court ," Fisher said. 'We need high-resolution images of coral communities scattered throughout the area and spread out, ranging in size from a small indoor bonsai to a small shrub'. .

To begin the study, the team used 3D seismic data from the Marine Energy Administration to identify 488 coral habitats in 40km radius around the spill site. From that list, they selected 29 positions that they assessed that contained corals affected by the spill. The team then used zipper and Sentry camera systems, an underwater self-propelled vehicle, which researchers programmed to move and return automatically through special areas to collect images of locations on the seabed only a few meters away. Finally, the research team used a vehicle called the Ultra-heavy-duty remote-operated vehicle (ROV) to acquire high-resolution images of coral reefs in locations they identified. .

'With boat cameras, ROV, we were able to collect beautiful, high-resolution images of coral reefs,' Fisher said. 'When we compared these images with known samples damaged by oil, all the signals showed a clear evidence of the two coral communities that identified the effects of Deepwater Horizon oil spill'. .

In the study of the effects of the Deepwater Horizon oil spill on coral communities, the team also found that two coral areas were caught in the commercial fishing route. These additional findings serve as a reminder that the Gulf of Mexico is being affected by various human activities.

Joining Fisher, the team has researchers including: Pen-Yuan Hsing, Samantha P. Berlet, Miles G. Saunders and Elizabeth A. Larcom from Penn State; Carl L. Kaiser, Dana R. Yoerger and Timothy M. Shank from Woods Hole Oceanographic Institution Research Institute; Harry H. Roberts from Louisiana State University, William W. Shedd from the Marine Energy Administration, Erik E. Cordes from Temple University; and James M. Brooks from TDI-Brooks International Inc.

The study was supported by the Assessment and Restoration Division of the National Oceanic and Atmospheric Administration (NOAA) and many other organizations.