Scientists, salvors cooperate to protect coralJan 23, 2013 12:38 PM
Diver Juan Vera removes coral near the salvage tug's anchor.
Vessel groundings are tough enough on coral. But in many cases salvage operations just make things worse, with dragging anchors and cables inflicting more damage than the initial impact of a hull.
To better protect reefs in U.S. territorial waters, the National Oceanic and Atmospheric Administration (NOAA) has been working with salvors to safeguard coral and move colonies out of harm’s way if necessary.
Sean Griffin, habitat restoration specialist at NOAA’s Office of Response and Restoration in Puerto Rico, said the agency has had an emergency response program in place for about six years to minimize damage after a grounding.
A salvage barge's stem anchor and cable share the sea floor with octocoral and a sponge.
“We’re working more and more with salvors in these areas as they go in, to try to be on the scene and help and advise on the best way to remove the vessel to reduce the amount of damage during the extraction,” he said.
Griffin was involved in coral preservation efforts on Mona Island, Puerto Rico, during the recent removal of the freighter Jireh by Resolve Marine Group. More than 1,000 corals were proactively removed from the salvage area and transplanted, including endangered elkhorn coral more than three feet in diameter.
“We coordinate with the Coast Guard and salvors to identify areas where they’re going to be dropping the anchors and cables, then we go in and clear out the corals beforehand so they won’t get crushed,” he said.
Corals typically are moved aside by divers and temporarily reattached to the reef, then are moved back to their original home when the salvage is complete. But with the Jireh operation occurring during peak hurricane season, some of the corals were reattached permanently on an adjacent reef so they would be less vulnerable to storms.
Griffin said that despite the diligence of NOAA dive teams at the Jireh site, some corals were lost when the weather turned violent.
“Given the condition of the bow, it was tough to get in there and work sometimes, and by the time we were able to address it, Tropical Storm Ernesto had passed by,” he said. “The swells reached about 20 feet from that and rotated the vessel counterclockwise, crushing a colony by the bow.”
Although Mona Island is uninhabited, it is adjacent to a busy shipping lane and is susceptible to groundings. One of the largest involved the 325-foot containership Fortuna Reefer, which damaged nearly seven acres of coral when it ran aground in July 1997. NOAA initiated an emergency restoration of the reef that was completed in October of that year.
In the U.S. Virgin Islands, the salvage of the 90-foot ferry Royal Miss Belmar after it grounded in July 2011 showcased cooperation between government agencies, the Nature Conservancy and Donjon Marine Co. The parties worked together to ensure that Donjon’s anchors were placed in predetermined positions to avoid damaging coral while the salvors did their job.
Griffin said while groundings are frequent in the Caribbean, an increase in collaboration with salvage companies has helped limit reef damage. That was the case during the removal of Jireh, which he called “extremely difficult” due to the isolation and lack of resources on Mona Island.
“I’ve never worked with Resolve before, but it worked out really well,” Griffin said. “They were very cooperative. It was just a very complicated operation.”