EX1711: November 29-December 21, 2017  Science Leads: Diva Amon and Charles Messing

1. Explore and discover vulnerable marine habitats – particularly high-density deep-sea coral and sponge communities
2. Explore areas relevant to resource managers such as Essential Fish Habitats, Habitat Areas of Particular Concern, and national marine sanctuaries and their potential expansion areas
3. Explore the diversity and distribution of benthic habitats – including bottom fish habitats, chemosynthetic, and deep-sea coral communities
4. Investigate the geology of the Gulf of Mexico
5. Explore U.S. maritime heritage by investigating sonar anomalies and characterizing shipwrecks
6. Acquire a foundation of ROV, sonar, and oceanographic data to better understand the characteristics of the water column and the fauna that live there
7. Collect high-resolution bathymetry in areas with no (or low quality) sonar data
8. Engage a broad spectrum of the scientific community and public in telepresence-based exploration and provide a foundation of publicly accessible data and information products to spur further exploration, research, and management activities

Through discussions and information stemming from NOAA and other stakeholders, priority areas have been identified for exploration. This expedition will explore deep coral and sponge communities, bottom fish habitats, seamounts, undersea canyons, shipwrecks, and a variety of chemosynthetic habitats including cold seeps, mud volcanoes and brine pools. This expedition will help to establish baseline information in the region to catalyze further exploration, research, and management activities.

Conducted 17 ROV dives, ranging in depth from 300 to 2,321 meters (984 to 7,615 feet) to explore the diversity and distribution of deep-sea habitats and associated marine communities in the Gulf of Mexico basin. Operations focused on characterizing deep-sea coral and sponge communities; bottomfish habitats; shipwrecks; and chemosynthetic habitats such as cold seeps, mud volcanoes, asphalt seeps, and brine pools. Midwater exploration at depths ranging from 300 to 900 meters (984 to 2,953 feet) was also conducted on four dives to investigate the diversity and abundance of the largely unknown pelagic fauna. Highlights from the dives include:

• Observed hundreds of different species of animals, including several potential new species, new records for the region, and several significant range extensions. Several organisms were also seen alive for the first time. Some observations of note included:
Novel, rare, and unusual deep-sea fishes, including a marine smelt at a shallow depth of 900 meters (2,953 feet);
• First in situ observation of a synaphobranchid eel and skate;
• Several swordfish observed at depth, including one feeding;
• Feather star gardens on hard substrates previously undocumented in the Gulf of Mexico and Western Atlantic;
• The first record of the crinoid family Hyocrinidae (a probable new species) in the tropical Western Atlantic, and a likely new and locally abundant species of Thalassometridae;
• At least four species of carnivorous sponges.
• Observed commercially important species including fishes (silver roughy and Darwin’s slimehead) and invertebrates (golden crab, red crab, and royal red shrimp).
• Collected 105 biological samples (32 primary and 73 associated and commensal taxa) on both geological and biological samples, several of which may be undescribed species.
• Documented at least nine high-density and high-diversity coral and sponge communities.
• Surveyed Five Habitat Areas of Particular Concern (HAPCs) proposed by the Gulf of Mexico Fishery Management Council in order to collect critical baseline information to inform science and management needs. Four of these sites hosted high-density deep coral and sponge communities and one had extensive chemosynthetic communities.
• Explored six Flower Garden Banks National Marine Sanctuary proposed expansion zones to collect critical baseline information to inform science and management needs. High-diversity and density coral and sponge communities were discovered at two of areas, including a spectacular Madrepora oculata-dominated coral garden. Chemosynthetic communities, including brine rivers, large mussel beds, and asphalt seeps were observed in five of these proposed expansion zones.
• Surveyed the wreck of an early 19th-century copper-clad merchant vessel carrying artifacts including glass bottles, ceramic and porcelain vessels, remnants of a suction bilge pump with cast-iron flywheels, an anchor, and a cast-iron stove. Carried out a series of video transects along and across the forepart of the wreck to supply imagery for a 3D digital reconstruction  (courtesy of BOEM) of the wreck courtesy. Chemosynthetic fauna were observed within the wreck, likely from the presence of the degrading wood structure.