A recent survey of the sea floor near the failed BP oil well in the Gulf of Mexico has uncovered a coral graveyard of deepwater coral species that were most likely damaged from the infamous recent oil spill and plume plaguing the gulf. Located seven miles southwest of the well, the gorgonian corals were discovered with many dead and dying specimens 4,500 feet below the surface. So far the scientific evidence is pointing to the oil spill and underwater plume as the likely cause.
Scientists aboard a National Oceanic and Atmospheric Administration research vessel discovered the affected area using a submersible robot equipped with cameras and sampling tools.Researchers have traced the probably path of the massive underwater oil plume that was in direct line with the devastated patch of coral that measured approximately 130 x 50 ft. (40 x 15m). Although it could take months to determine whether it was in fact the leaked oil or dispersant killed the corals.
According to Charles Fisher, a marine biologist from Pennsylvania State University and chief scientist on the federal government financed expedition, the documented presence of oil plumes in the area, the proximity to BP’s well and the recent nature of the die-off make it highly likely that the spill was responsible.
As we see in our own systems, as corals become stressed they produce mucus that traps debris. The evidence shows the corals most likely have been getting clogged with toxic debris and literally rotting away the last few months.
Since this research is part of an ongoing effort to document the life on the Gulf of Mexico seafloor, coral samples can be take and compared to previous ones to note the changes in tissue and genetic structure. These samples can also be analyzed for traces of oil or dispersant.
The expedition that found the coral death site was part of an ongoing effort to document life on the Gulf floor, so these coral samples can be compared with previous samples to measure changes in tissue and genetic structure. The new samples will also be checked for oil and dispersant residue.
Although some corals may appear to be healthy, they may have suffered other ways including genetic mutations or losing the ability to reproduce. “If they’re not reproducing, they’re not producing larvae and they’re not going to be able to recolonise that area,” says Rhian Waller, a biological oceanographer at the University of Hawai’i at Manoa in Honolulu, who was not part of the team.
The team will continue their survey in early December that includes 25 other sites that may have been affected by the plume and “there could be more bad news to come,” says team member Erik Cordes, a biologist at Temple University in Philadelphia.
[via NY Times and New Scientist]
