A large black coral along the edge of a very steep cliff that was heavily encrusted with coral and sponges.

A large black coral along the edge of a very steep cliff that was heavily encrusted with coral and sponges. Image courtesy of NOAA Okeanos Explorer Program, Our Deepwater Backyard: Exploring Atlantic Canyons and Seamounts 2014. Download larger version (jpg, 1.7 MB).

Dive 08 - Gosnold Seamount
September 28, 2014
38°, 18.143' N ; 062°, 30.643' W, 2,138 meters
Access Dive Summary and ROV Data

Okeanos Explorer EX1404L3

Dive 08: Gosnold Seamount. Video courtesy of NOAA Office of Ocean Exploration and Research. Download (mp4, 54.0 MB)

Today, remotely operated vehicle Deep Discoverer (D2) conducted the first-ever exploration of Gosnold Seamount and discovered an incredible landscape of deep-sea corals. D2 landed on hard bottom at a depth of 2,138 meters with several coral colonies, anemones, and sponges. During our transit up the ridge, we encountered 15 individual fish of eight different taxa, several crinoids, a diversity of sponges, coral rubble, hydroids, sea cucumbers, shrimp, sea stars, a dandelion siphonophore, urchins, brittle stars, barnacles, and sea spiders. At the top of the rift arm, D2 explored a sediment plane with manganese-crusted pebbles and similar encrusting fauna as seen down slope on the few larger hard-rock areas. The most abundant fauna throughout the dive were sponges and corals, primarily large brambles of bamboo corals and precious corals. Other corals present included black corals, cup corals, primnoid corals. Highlights of the dive included an almost vertical rock wall feature with a high density and diversity of corals, a rare sun star, a hermit crab using a sponge instead of a shell for its home, and a rare coral-eating mollusk (aplacophora). D2 was recovered from 1,850 meters after two deployments of the Sepoke on the sediment plane, which indicated that sediment accumulation was less than 15 centimeters.