A Newly Discovered Coral Reef on America’s Doorstep

newly discovered coral reef
Alvin collects a sample of Lophelia pertusa from an extensive mound of both dead and live coral.

A NEWLY DISCOVERED CORAL REEF off the U.S.’s mid-Atlantic coast  stretches for some 85 miles, dense with stony Lophelia pertusa, a branching deep-sea, cold-water coral.

A half-mile below the ocean surface, the “new” reef has “mountains” of coral, according to researchers. It’s situated about 160 miles off Charleston, S.C.

DEEP SEARCH – A VOYAGE OF DISCOVERY

The newly discovered coral reef was identified by scientists from the National Oceanic and Atmospheric Administration and other agencies as part of DEEP SEARCH, a five-year project to explore the deep waters off Virginia and the Carolinas.

Its presence was suggested by sonar mapping of the region by the NOAA research vessel Okeanos Explorer earlier this year. The follow-up voyage by the research ship Atlantis in late summer was equipped with the manned submersible Alvin.

newly discovered coral reef
On the third dive of the expedition, the DEEP SEARCH team discovered thriving Lophelia pertusa reefs in a region further offshore and in deeper water than other known Lophelia reefs in the US Atlantic.

“AS FAR AS THE EYE COULD SEE…”

When the ROV reached the seafloor, Chief Scientist Erik Cordes wrote on the NOAA website,  “there was coral skeleton as far as the eye could see, throughout the entire dive. But this was only our first hint, a few short hours of observation, of what may be waiting for us in the area.”

Describing the newly discovered coral reef, he added, “We were all surprised to find that these mounds were made by Lophelia pertusa, along with some other deep-sea corals, and that they were thriving in these conditions—further offshore and deeper than we had ever seen them before.”

LOPHELIA PERTUSA

Usually found at depths of 660-3,300 feet/200-1,000 meters, Lophelia pertusa is a reef-building coral that’s too far below the lighted zone to be helped by the presence of photosynthetic algae. Its branching architecture would maximize its polyps’ access to plankton-laden currents.

The L. pertusa reef visited by Alvin showed that new Lophelia, like most corals, grows atop old skeletons, creating mound structures 260-330 feet/80-100 meters high. L. pertusa is known to grow throughout the Atlantic, the Caribbean, the Gulf of Mexico and even the western Mediterranean.

It’s slow-growing and apparently long-lived. Radiocarbon dating has shown that another L. pertusa reef in the Atlantic to be as old as 40,000 years, with individual structures as much as 1,000 years old.

A time-lapse video compresses eight-hours of Alvin’s initial voyage to the newly discovered coral reef into three minutes.

THE DEEP SEARCH MISSION

DEEP SEARCH is a collaboration of NOAA, the Bureau of Ocean Energy Management and the U.S. Geological Survey.  R/V Atlantis and Alvin are vessels operated the Woods Hole Oceanographic Institution.

The DEEP SEARCH mission comes against a backdrop of the Trump administration’s proposal to allow energy companies to drill and mine in waters along the U.S. continental shelf, including protected areas. Although it’s still unclear what waters might be vulnerable, one of the project’s goals is to aid the BOEM in identifying new, fragile habitats as part of a management plan.

PRINCIPAL SOURCES:  Mission Summary: What We Have Learned from DEEP SEARCH Expedition AT-41,” NOAA; “Dive Three: Exciting Finds on Our First Coral Dive!” NOAA;  “Scientists Discover Giant Deep-Sea Coral Reef Off Atlantic Coast,” MSN; “Scientists discovered a coral reef — almost as long as Delaware — hidden off the coast of Charleston,” Washington Post; “Lophelia pertusa,” Encyclopedia of Life;Lophelia,” Wikipedia.