Dive 08: Richardson Scarp
Date: June 22, 2018
Location: Lat: 32.09482827°, Lon: -77.54584052°
Dive Depth Range:: 868 - 1,006 meters (2,848 - 3,301 feet)


Location of NOAA Ship Okeanos Explorer on June 22, 2018.

Location of NOAA Ship Okeanos Explorer on June 22, 2018. Download larger version (jpg, 388 KB).

3D view of the planned ROV track for Dive 08 shown as an orange line. The background represents the seafloor depth color-coded with slope in degrees. The warmer the color, the steeper the slope.

Three-dimensional view of the planned ROV track for Dive 08, shown as an orange line. The background represents the seafloor depth color-coded with slope in degrees; the warmer the color, the steeper the slope. Download larger version (jpg, 918 KB).





Today’s dive was at Richardson Scarp, a steep feature near the edge of the northern Blake Plateau, at the upper depths of the Blake Escarpment. This site is within a large under-explored area of the Miami Stetson Habitat Area of Particular Concern and is a high priority region for the DEEP SEARCH project, with the primary objective to identify presence and/or absence of deepwater corals and benthic communities in these areas. Some of this region was first mapped during the first leg of this expedition and last night, the mapping team collected new data over what would become today's dive site. From these data, the mission team identified an interesting scarp feature at 05:00 this morning and were on station and ready to dive it by 08:00.

Two golden crabs, a commercially important species, seen during Dive 08 of the Windows to the Deep 2018 expedition. Based on their behavior the scientists speculated that the pair was mating.

Two golden crabs, a commercially important species, seen during Dive 08 of the Windows to the Deep 2018 expedition. Based on their behavior the scientists speculated that the pair was mating. Image courtesy of the NOAA Office of Ocean Exploration and Research, Windows to the Deep 2018. Download larger version (jpg, 724 KB).

The remotely operated vehicle (ROV) Deep Discoverer was on the seafloor from 13:27:38 - 19:56:49 UTC. The dive started around 990 meters (3,248 feet) depth, at the base of the scarp in an area with sediment-covered rock. The ROV scaled the scarp, which had numerous stair-step terraces with different rocks exposed. Manganese-nodules were seen in abundance mid-way up the scarp on two of the flat-lying terraces. The slope of the scarp was often more than 30 degrees, including a 30-meter-high vertical wall. The top of the feature was flat-lying, sediment-covered rock where the dive ended, at 868 meters (about 2,848 feet) depth. During the dive, there was a fast-moving current, which likely leads to the success of the sessile species because it brings more food, for example marine snow, to the filter feeders, while the rocky substrate provided a stable place for attachment.

Through images shared by NOAA Ship Okeanos Explorer’s eye in the deep sea, the remotely operated vehicle Deep Discoverer, we have been treated to amazing insights into the lives and behaviors of a variety of deep-sea decapod crustaceans. Given the remoteness of their habitats, we very seldom have opportunities to see deep-sea organisms in their natural environment, so we know very little about their life history and behavior. On this particular day, we were provided a glimpse into the secret lives of two types of deep-sea crabs, Neolithodes sp. and Chaceon sp. Read the full description of the video here. Video courtesy of the NOAA Office of Ocean Exploration and Research, Windows to the Deep 2018. Download larger version (mp4, 53.4 MB).

Species seen throughout the dive included black corals, stony corals, octocorals including a bubblegum coral, soft corals, cup corals, cutthroat eels, cusk eels, rattails, true shrimp, sea stars, squat lobsters, a large (30 centimeters tall) carnivorous sponge, anglerfish, brittle stars, polychaete worm, hermit crabs, glass sponges, demosponges, anemones, cookie star, a skillet skate, and crabs including two golden crabs possibly mating. Another highlight for the dive was a male crab eating another crab species while the female wandered in what appeared to be a defensive posture with her claws up. Biological samples of some of the corals seen during the dive and two rocks collected will provide the scientists with more important information on the fauna in this region and the geologic history. Once available, review the dive summary for a additional information about the fauna seen and collections made.

Each Friday, the mission team hopes for an octopus so they can celebrate Octopus Friday, and this dive did not disappoint. The team observed an octopus around 892 meters (about 2,927 feet) during the dive.

While still very far from the nearest landmass, the team still observed some marine debris on this dive in the form of a net. Scientists will be on the lookout for more marine debris as they survey a wreck potentially from the 19th century tomorrow.

This large bubblegum coral as well as several smaller colonies, was seen on a near vertical wall during the dive at Richardson Scarp for the Windows to the Deep 2018 expedition.

This large bubblegum coral as well as several smaller colonies, was seen on a near vertical wall during the dive at Richardson Scarp for the Windows to the Deep 2018 expedition. Image courtesy of the NOAA Office of Ocean Exploration and Research, Windows to the Deep 2018. Download larger version (jpg, 722 KB).

Each Friday the mission team hopes for an octopus so they can celebrate Octopus Friday and this dive did not disappoint. The team observed an octopus around 892 meters (about 2,927 feet) during Dive 08 of the Windows to the Deep 2018.

Each Friday the mission team hopes for an octopus so they can celebrate Octopus Friday and this dive did not disappoint. The team observed an octopus around 892 meters (about 2,927 feet) during Dive 08 of the Windows to the Deep 2018. Image courtesy of the NOAA Office of Ocean Exploration and Research, Windows to the Deep 2018. Download larger version (jpg, 788 KB).