A bivalve surrounded by cup corals and soft corals are attached to a steep cliff face. A squat lobster is associated with soft coral on the lower left, and a jellyfish swims to the left of the bivalve. Image courtesy of the NOAA Office of Ocean Exploration and Research, Northeast U.S. Canyons Expedition 2013. Download larger version (jpg, 1.4 MB).
Highlights from exploration of Hydrographer Canyon along a section of the western wall at depths from approximately 1,300 to 1,420 meters. Video courtesy of the NOAA Office of Ocean Exploration and Research, Northeast U.S. Canyons Expedition 2013. Download video (mp4, 52.9 MB).
A Rhinochimera (Harriotta sp.) swims 10 meters above the seafloor in Hydrographer Canyon. Video courtesy of the NOAA Office of Ocean Exploration and Research, Northeast U.S. Canyons Expedition 2013.. Download video (mp4, 3.2 MB).
Dive 05 was conducted in Hydrographer Canyon, exploring a section of the western wall from approximately 1,300 to 1,420 meters for deep-sea coral and sponge habitats and other deep-water fauna and to examine canyon geomorphology. At least 12 species of deep-sea coral along with numerous species of associates (shrimps, squat lobsters, isopods, amphipods) on the coral colonies were observed throughout this dive, and a strong current persisted out of the northwest. The Deep Discoverer remotely operated vehicle reached the seafloor at a depth of 1,418 meters. The bottom consisted of large, detached angular sedimentary (compacted mud) blocks draped with bioturbated sediment, suggesting that the sediments had been there for some time. During transit to the first dive waypoint, several species of corals including a black coral were seen, as well as individual small corals indicative of new recruits, and numerous octopods under rock ledges. Transiting up a steep, sediment covered slope towards waypoint 2, a spider crab, white octopus, sea lily, and rat-tail fish were observed. A vertical cliff face was encountered at 1,376 meters covered with at least eight different species of deep-sea corals. We continued to transit over blocky rock outcrops with extensive bioerosion, likely sedimentary mudstone, and extensive coral gardens until a more sedimented slope was crossed. At 1,352 meters, we conducted our final transit to waypoint 3, continuing over a sedimented slope with numerous burrows and xenophyophores, single-celled organisms that can reach at least 10 centimeters in diameter. Another large vertical wall was discovered near the end of the dive with octocorals and cup corals. Numerous columnar structures within and dislodged at the bottom of the wall face were observed, as was a small slope failure.