|Coastwatch Autumn 2003:
Science on the High Seas: The Oculina Banks Research Cruise
By: Pam Smith
North CarolinaSea Grant
for a link to the article click here
It’s late afternoon when the M/V Liberty Star steams out of Port Canaveral, Fla. — past charter boats in from a day of Gulf Stream fishing, and on past commercial fishing vessels draped with nets still wet from hoisting the catch-of-the-day.
The determined pace means Liberty Star— a NASA space-shuttle support ship — will reach its destination 30 miles offshore well before the sun slips below the horizon.
Topside, Andy Shepard thinks out loud. “There’s plenty of daylight for a launch.”
But this launch won’t generate a deep-space probe.
On the contrary. His crew will launch an array of high-tech instruments to explore the deep-ocean realm of the Oculina Banks — the only known deepwater reef in the world made by Oculina varicosa, or Ivory Tree coral. This pure-white oddity grows in mounds and pinnacles along the edge of Florida’s continental shelf, below the Gulf Stream Florida Current at depths of 200 to 300 feet.
Shepard, who is coordinating the 10-day scientific mission, is director of a National Undersea Research Center based at the University of North Carolina at Wilmington and funded by the National Oceanic and Atmospheric Administration (NOAA).
He has assembled an interdisciplinary team of researchers, technicians, students and observers from a number of organizations. They will help document the status of the coral habitat and fish populations in the 300-square mile Oculina Habitat of Particular Concern (OHAPC). A 92-square mile segment of the offshore formation first became a Marine Protected Area (MPA) nearly 20 years ago.
The 2003 Oculina expedition is the latest in a series — largely sponsored by NOAA Fisheries — designed to produce scientific data to support sound habitat protection and fisheries management decisions.
Scientists fear that much of the unique coral reef ecosystem continues to be reduced to rubble, mainly from bottom-fishing activities. The questions to be answered: How much coral is intact? Is it enough to provide habitat for deepwater fish, such as snapper and grouper?
Ocean research is costly, and the NASA partnership stretches limited research dollars. NASA provides a state-of-the-art ship as a platform for operations at sea, as well as a highly trained crew to launch and maneuver undersea research technologies. NOAA’s Remotely Operated Vehicle (ROV) and NASA’s Passive Acoustic Monitoring System (PAMS) will enable researchers to “see and hear” ocean floor activities.
Much of what already is known about Oculina Banks is the result of decades of research by John Reed, chief scientist on the mission and at Harbor Branch Oceanographic Institution (HBOI) in Fort Pierce, Fla. In 1975, scientists there discovered the rare coral biotherms — reefs built by animals.
Soon after, Reed began studying Oculina Banks. He described live coral thickets, mounds and pinnacles up to 30 meters high and teeming with life. Reed recorded a healthy ecosystem supporting 250 species of mollusks, 50 species of crabs and shrimp, and some 70 species of fish — including various grouper, snapper, black drum, porgies, sea bass, amberjack, angelfish, sharks, rays and small reef fish.
Continuing studies demonstrate steady declines in both live coral and fish populations — in spite of having federal protection since 1984.
That’s when NOAA Fisheries’ South Atlantic Fisheries Management Council designated the 92-square mile area as the OHAPC) — an MPA classification that called for close monitoring and banned the use of bottom-tending gear such as trawls, dredges and fish traps.
Subsequent research by HBOI’s Grant Gilmore and Florida State University’s Chris Koenig showed dramatic loss of fish populations, primarily grouper and snapper.
So, in 1994 the council classified the area as the Experimental Oculina Research Reserve for a 10-year period to protect the coral habitat and dwindling snapper and grouper populations in the reserve.
Then, in 2000 the council expanded the OHAPC to encompass 300-square miles — about 60 nautical miles long and 5 nautical miles wide — stretching from Cape Canaveral to Fort Pierce.
The moratorium on hook-and-line bottom fishing for all snapper and grouper species applies only to the 92-square mile experimental research reserve. The entire area remains off-limits to bottom trawls, dredges, fish traps and anchoring — but commercial and recreational fishers may surface troll for pelagic fish, such as wahoo, tuna, dolphin and sailfish.
The goal is to protect the rare coral, protect fish habitat, and assist in the management of important commercial and recreational fisheries.
Life as a coral
Corals are primitive animals made up of colonies of polyps. Unlike their shallow-water reef cousins, the deep-water species, such as Oculina varicosa, lack symbiotic algae, or zooxanthellae, to supply nourishment and color. Instead, tentacles that encircle their miniscule, soft bodies capture plankton carried by deep-flowing currents for food and energy.
The Oculina varicosa corals secrete limestone, expanding their branch-like skeletons as they grow upward, ever-so-slowly, at a rate of about one-half inch per year, building the reef as they go. A five-foot coral “tree” may be a century old.
Simple as it is, coral is the keystone of complex ecosystems.
Rock shrimp, a prime commercial target in Florida, are attracted to the nooks and crannies of coral reefs for food and shelter. During their migratory journeys, pelagic fish, such as tuna, feed on baitfish associated with reefs. The Oculina Banks are a well-known breeding site for many species of snapper and grouper. Less migratory, these fishes stay closer to home, and so, rely on the reef’s baitfish for sustenance for much of their long lives.
Oculina Banks — with its branching coral clusters and limestone shelves and ledges — has provided critical habitat for marine life for millennia. About 90 percent of the Oculina varicosa has been damaged or destroyed during the past two decades, Koenig’s research shows.
So, scientists want to know if coral restoration is feasible. During the mission they’ll revisit several areas to check on previously placed artificial reef structures that were “seeded” with sprigs of live coral.
They also will use a three-dimensional map of the reserve bottom made using multi-beam sonar during a 2002 cruise on the same ship. The ROV dives will be used to “ground truth” this map, Reed says. This will establish important baseline scientific data that can be used to track future changes in the Oculina Banks ecosystem.
A Sense of Urgency
On board Liberty Star, there is a sense of urgency to get on with the mission.
The research team is anxious to make up for time lost returning to port to retrieve parts for the ROV disabled during a first-day dive. Repairs are completed just as the ship approaches Oculina Banks.
On the bridge, Shepard and Reed review charts and pinpoint dive coordinates with Capt. Bren Wade and First Mate Walt Adams — members of the United Space Alliance crew whose usual contract work with NASA involves retrieving space-shuttle rockets at sea.
For this operation, the crane operator lowers the tethered ROV into the sea until it hovers just above bottom. All the while, the captain maneuvers the ship against the strong current that flows at two to three knots, allowing the ROV to “fly” along the bottom at one-half to one knot.
In all, 23 ROV dives are scheduled, involving criss-cross sweeps over each site. The list includes historic sites not seen for 25 years. The ROV also will peer into unexplored areas inside and outside the reserve.
The launch begins and Shepard watches until the ROV disappears into the waves, then slips through the hatch to join Reed in the control room. There, Lance Horn is at the monitor, ready to “pilot” the ROV across the site.
Thrust engines roar and the monitor flickers the first glimpse of the reef transmitted from the ROV video camera. For the next tense hour, Horn — in constant communication with the bridge officers and the crane operator — controls the depth, pitch and yaw of the robot; points the video camera; and illuminates reef features and marine life.
Seated in front of the console, Reed and Shepard are joined by Robert Brock, a fish biologist from NOAA Fisheries headquarters in Silver Spring, Md., and Stacey Harter, a fish biologist from NOAA Fisheries in Panama City, Fla. The team will identify, videotape and photograph reef characteristics and fish populations.
Lights, camera, action
It’s an intense “I Spy” video game. A feature comes in view, and one scientist calls out a general term. Another adds to the description, and so on.
Occasionally, they spot a cluster of live Oculina varicosa in areas where it had not been recorded before.
“Nice, John! We found more,” Shepard exclaims at one unexpected sighting.
And so the ROV dives go, with peaks of excitement at spotting an artificial reef ball with intact, live coral and a couple of grouper swimming in and out of the igloo-like structure.
Spirits plummet at seeing clusters of half-dead coral, wrapped with long-line. Pieces of nets, cable and trawls on the reef testify to illegal bottom-fishing activities.
The coral, as fragile as china, is no match for the sweeping action of such equipment — a reality brought home as the camera reveals the bottom littered with broken coral debris. Two decades ago, Reed recorded healthy stands of Oculina varicosa in many of the same areas.
More disturbing, perhaps, is what they do not see.
They do not see formations of live coral the size of Volkswagen beetles Reed described in the mid-1970s. Nor do they see large congregations of grouper, snapper, or black drum, once in abundance on Oculina Banks.
Reed, who has logged countless dives from the Harbor Branch submersible, remembers a time when the area was thick with curious fish.
Once, a caliper he was using to measure coral growth got the attention of a 300-pound Warsaw grouper. The fish swam closer and surprised Reed by snatching the caliper from his hand. The monster quickly retreated, then stopped to see if Reed was following. Reed recovered the caliper and went back to work, only to have the playful Warsaw grouper return for another round of “take away.”
“He was like a giant Labrador retriever,” Reed recalls.
Sadly on this trip, ROV eyes do not spot a single Warsaw grouper.
The mission is carefully orchestrated. Each day, new people are shuttled out to the M/V Liberty Star to observe the scientific mission for a day. The roster includes resource managers, fish biologists, educators and journalists.
The mission is receiving positive regional media exposure, just as Shepard hoped.
He believes that education and outreach should be integral components of research projects, especially ocean exploration. How else, he asks rhetorically, can the public begin to understand a realm of life that they cannot see?
Earlier in the mission, NASA media and technology specialists facilitated a live Web cast. Students in mainland classrooms were connected to Oculina Banks during an interactive hook-up. Leslie Sautter, director of NOAA’s Project Oceanica at the College of Charleston, hosted three, one-hour segments. Each ended in a question and answer session, with mission team members answering queries submitted electronically.
Dewey Golub, Oceanica’s educator-writer and Web specialist, posts daily logs and images from the mission on a dedicated Web site, http://oceanica.cofc.edu .
The Oculina Banks research demonstrates that marine science is a very integrated discipline, Sautter says.
Sautter, a geologist and educator, is directing the collection of sediment samples. An apparatus is lowered from the ship to scoop up sediment from various sites. She will analyze the samples with Cathy Scanlon, a colleague at Woods Hole, in search of tiny shelled zooplankton called forams.
“We will be looking for a genus that dominates each environment. We expect that they will be very different from site to site,” she says. A map plotting the results will become part of the baseline data on Oculina Banks. Shifts in predominant genera could be environmental indicators, she says.
Even the best-planned mission can present unexpected hurdles. The ship develops problems, and the entire cohort transfers to M/V Freedom Star, a NASA sister ship maintained by United Space Alliance.
The ROV floods two additional times. But, frantic repair work keeps the dive schedule on target, ensuring enough time to test the PAMS technology. For that, the ship steams out of reserve to an area near Sebstian Inlet at more shallow ocean depths.
Without a hitch, NASA divers position three PAMS units on the bottom, about 100 feet apart. Gilmore, now part of the Dynamac/NASA research team, helped develop the technology to monitor shuttle launch noise in the lagoons and wildlife refuge surrounding the Kennedy Space Center.
Now, for two days and nights the units will listen and record fish sounds — each with a distinct voiceprint. The black drum lives up to his name, producing the steady beat of a bongo drum. Other fish sounds are not as recognizable to an untrained ear. Gilmore and colleagues will analyze the recordings.
Like humans, most fish make sounds during social interaction. Distinguishing spawning males calling to females is valuable for fishery management decisions, Gilmore explains. It is critical to know when spawning occurs in order to protect the fishery.
“If they don’t live long enough to spawn, there will be no fish,” Gilmore says.
Some see the PAMS technology as a potential enforcement tool in MPAs. The sensitive “ears” could identify dropping anchors or gear. Boat motors, which produce identifiable voiceprints, could be matched to illegal activity.
With all objectives met, Shepard and Reed can safely say, “Mission accomplished.” In 10 days, 23 ROV dives produced 40 hours of underwater videotape and 2,000 digital still shots to add to the accumulating scientific data.
The images also provide convincing evidence of illegal fishing activities in the OHAPC. Enforcement, they say, clearly is an issue for the fisheries council to tackle.
The scientists welcome the news that the South Atlantic Fishery Management Council is recommending that the Department of Commerce continue the ban on bottom-gear in the original 92-square mile EORR until 2014. The closure of this segment within the larger OHAPC was scheduled to sunset in 2004 if not renewed.
In addition, NOAA Fisheries Law Enforcement promise to step up efforts in the closed area. A vessel monitoring system may be deployed on shrimp trawlers in the region in 2004.
Reed, Shepard and Koenig submitted scientific data from the 2001 research mission prior to the fisheries council meeting taking up the reserve status.
Koenig also was among 60 people expressing opinions in person. He wanted to underscore the ecological value of Oculina Banks. Speaking out, he says, helps give the scientific point of view public exposure.
Public exposure of Oculina Banks is critical. If no one knows about it, no one can respond to the need to continue its protection, he says.
Perhaps media attention to the 2003 mission was a factor. But, Koenig was pleasantly surprised to hear support for the experimental reserve from many in commercial fishing arena.
“They are beginning to understand that an MPA makes a good neighbor — especially in the Gulf Stream, where strong currents can carry the larvae of spawning fish well beyond MPA boundaries,” says Koenig.
This understanding, Shepard adds, can and should provide the science foundation for selecting future marine protected areas. Six of the council’s candidate sites, like the Oculina Banks, are on the high seas, beneath the Gulf Stream.Look for an upcoming publication focusing on Marine Protected Areas. This MOA primer — meant to contribute to productive regional discussion — is a collaborative effort by the North Carolina, South Carolina, Georgia and Florida Sea Grant programs.
The South Atlantic Marine Fisheries Management Council is expected to
hold a series of public meetings later this year for the consideration
of candidate MPA sites in the region.