Successful Multi-Year Effort to Study Deep-Sea Corals and Sponges in the Southeast United States

January 25, 2022

A NOAA collaboration with extensive local, academic, and federal partners has greatly expanded our understanding of deep-sea coral and sponge ecosystems in the southeast United States.

Feature Story |

Southeast

A photo of dense fields of Lophelia pertusa, a common reef-building coral, found on the Blake Plateau knolls. The corals are white in color, which is healthy - deep-sea corals don’t rely on symbiotic algae so they can’t bleach.

Researchers discovered thriving Lophelia pertusa reefs in a region farther offshore and in deeper water than other known Lophelia reefs in the U.S. Atlantic. This image of “Million Mounds” shows healthy habitat with extremely high live coral cover. Credit: NOAA Ocean Exploration.

NOAA’s Deep Sea Coral Research and Technology Program has completed its multi-year highly collaborative effort, known as the Southeast Deep Coral Initiative. Initiative collaborators explored and characterized deep-sea coral and sponge ecosystems in the federal waters of the U.S. South Atlantic, Gulf of Mexico, and U.S. Caribbean. Researchers completed 21 expeditions to survey deep-sea coral and sponge ecosystems using ships, submersibles (including remotely and autonomously operated vehicles), and other equipment. Complementary research projects conducted in partnership with universities focused on seafloor mapping, species identification, habitat suitability modelling, environmental and oceanographic monitoring, and data analysis.

A photo of a purple and yellow yellowfin flagfish situated on the seafloor between a colony of lace corals in U.S. Caribbean waters — This yellowfin flagfish was photographed between a colony of lace corals during a 2018 expedition to collect information on unknown and poorly understood deep water areas surrounding Puerto Rico and the U.S. Virgin Islands. Credit: NOAA Ocean Exploration.

Initiative Highlights

Coral and Sponge Observations

Expeditions resulted in a 450 percent increase in the number of coral and sponge observations in the West Florida Wall. This area is of particular interest to the Gulf of Mexico Fishery Management Council due to its significant coral aggregations. These records informed the Council’s decision to combine three small proposed protected areas into one much larger and more effective one.

Massive Coral Mounds

Mapping revealed that the central Blake Plateau, which was originally thought to be soft sediment, is actually covered with extensive mound features. They are composed primarily of Lophelia pertusa coral communities. Researchers have named this ecosystem “Million Mounds” and it contains some of the thickest Lophelia aggregates in the region.

Video of Deep-Sea Coral Habitats

In a collaborative research project in Puerto Rico, local anglers deployed GoPro™ drop cameras to record video of deep-sea habitats. The project improved the understanding of relationships between commercially important snappers and coral and sponge communities.

Successful telepresence-enabled expeditions allowed real-time participation from shore. Scientists involved more than 45 students, from the high school to Ph.D. level. They invited them to viewings and held laboratory classes to give the students hands-on experience with deep-sea corals.

Students from College of Charleston (standing left) with initiative Lead Scientist Peter Etnoyer (standing right) in Charleston’s “pop-up” Exploration Command Center during a NOAA Ship Okeanos Explorer watch party at Hollings Marine Laboratory. — Students from College of Charleston (left) with initiative Lead Scientist Peter Etnoyer (standing right) in Charleston’s “pop-up” Exploration Command Center during a NOAA Ship Okeanos Explorer watch party at Hollings Marine Laboratory. Credit: College of Charleston/Bob Podolsky.

Public Geodatabase

Researchers developed a web-accessible public geodatabase to share habitat suitability models, coral and sponge observations, submersible dive locations, and managed area boundaries.

These collective efforts provided important information needed to support the management of fishing and other activities that may affect deep-sea coral ecosystems throughout the region.

Expanding Partnerships

The Southeast Deep Coral Initiative, which began in 2016, was led by NOAA’s National Centers for Coastal Ocean Science, in collaboration with NOAA Fisheries, NOAA Ocean Exploration and the Office of National Marine Sanctuaries. This effort was made possible through a variety of funding sources, and extensive local, academic, and federal partners. NOAA has published the final initiative report.