A team of university, state and federal scientists is close to wrapping its exploration of a little known deep reef, Pulley Ridge, where spectacular plate coral colonies blanket the sea floor and red groupers actually help create habitat.
Scientists believe this ecosystem, which lies 33 miles northwest of the western most boundary of the Florida Keys National Marine Sanctuary, serves as a source of invertebrate and fish larvae riding the Loop Current’s easterly and southward curvature from Florida’s coast to the sanctuary.
The deepest known photosynthetic coral reef off the continental U.S., Pulley Ridge, 180 feet to 240 feet down is home to giant barrel sponges and largely undisturbed plate corals. Nearby, pits in the seafloor created by red groupers make for a complex habitat that supports a wide range of other species — including colorful fish such as the purple reef fish and tasty ones such as vermillion snapper.
Aboard the University of Miami Rosenstiel School of Marine and Atmospheric Science’s F.G. Walton Smith, the team started its final field Aug. 22 and plans to wrap it Friday. Using the remotely operated vehicle Mohawk, owned by the National Marine Sanctuary Foundation and the Flower Garden Banks National Marine Sanctuary and operated by the Undersea Vehicles Program at the University of North Carolina-Wilmington, the team has been collecting seafloor images and taking samples of marine life.
The images will help scientists characterize the seafloor and fish communities and the samples of marine life will help identify specific species.
One of the highlights of the multi-year research project was last year’s discovery of a large patch, greater than 65 yards across, of nearly continuous plate coral.
“We will be looking at the science from this project to see how closely fish, corals, and marine life in Pulley Ridge are connected to the Florida Keys,” sanctuary Superintendent Sean Morton said.
Pulley Ridge is one of the areas that the Sanctuary Advisory Council requested the National Oceanic and Atmospheric Administration analyze for potential inclusion within the sanctuary. The Gulf of Mexico Fishery Management Council designated it a Habitat Area of Particular Concern in 2005 because it fits the criteria of being rare, ecologically important and susceptible to environmental stress (e.g., oil spills).
Specific fishing regulations in place there prohibit bottom anchoring by fishing vessels, bottom trawling, longlines, buoy gear and all traps and pots. However, the Habitat Area of Particular Concern designation does not protect Pulley Ridge from anchoring by non-fishing vessels, impacts from divers or from any other non-extractive uses, all of which can impact the health of the reef. Also, some of the more newly discovered reefs at Pulley Ridge are not protected as part of the designation.
If it were to become part of the sanctuary, additional management capabilities available under the National Marine Sanctuaries Act would provide further protection to Pulley Ridge from non-fishing related activities such as anchoring, discharges and dumping, cable laying or oil, gas, and mineral extraction.
“Understanding the connectivity of Pulley Ridge to the greater Florida Keys ecosystem will be critical for determining whether the boundaries of the Florida Keys National Marine Sanctuary should be expanded to include Pulley Ridge,” Morton said.
This was provided by the Florida Keys National Marine Sanctuary.