The Deepwater Horizon spill hit coral harder than previously thought
Wednesday, July 30, 2014, 9:00 AM - It's been more than four years since an explosion aboard the Deepwater Horizon oil platform killed 11 and unleashed the largest oil spill in history.
Now, a new study from Penn State University says the impact of the spill on coral communities was more than predicted.
"The footprint of the impact of the spill on coral communities is both deeper and wider than previous data indicated," Prof. Charles Fisher, the lead author of the research, said in a release. "This study very clearly shows that multiple coral communities, up to 22 km from the spill site and at depths of over 1,800 metres, were impacted by the spill."
The team chose to study coral for the spill's long-term impact since, even when the organisms that make up a reef die, they leave being a "skeleton" of minerals that does not decompose. They looked at the current state of one coral community known to have been impacted, and compared it to coral at two other sites discovered in 2011. Both showed signs of patchy brown growth not found on healthy colonies.
Despite coral's suitability for study, it's not very common in the Gulf of Mexico, so the study's authors had to look very hard to find them, 3D seismic data, towed camera systems and autonomous underwater vehicles to find and photograph them.
"We were looking for coral communities at depths of over 1,000 metres that are often smaller than the size of a tennis court," Fisher said. "We needed high resolution images of the coral colonies that are scattered across these communities and that range in size from a small houseplant to a small shrub."
The results of the study will be published in the journal Proceedings of the National Academy of Sciences.