Deep Connections 2019: Exploring Atlantic Canyons and Seamounts of the U.S. and Canada

Dive 05: Unnamed Minor Canyon

Date: September 2, 2019
Location: Lat: 40.90572°, Lon: -66.50047°
Dive Depth Range: 535 - 754 meters (1,756 - 2,475 feet)
Access Dive Summary and ROV Data

Three Atlantic Halibut (Hippoglossus hippoglossus) were spotted in an unnamed deep-sea canyon north of Kinlan Canyon, located off the New England coast. Three observations in such a short period of time suggests that this canyon may be critical habitat for this endangered species. Video courtesy of the NOAA Office of Ocean Exploration and Research, Deep Connections 2019. Download larger version (mp4, 102 MB).

Today we dove on the southern wall of an unnamed minor canyon north of Kinlan Canyon. Major shelf-incised canyons in this region have received a fair amount of attention in terms of exploration; however, minor slope canyons like the one targeted during this dive remain mostly unexplored. The planned dive track was designed to cross the canyon axis in order to assess the geologically recent sediment transport history of the canyon, as well as the benthic communities of the area.

A large endangered Atlantic Halibut (Hippoglossus hippoglossus) seen resting on the seafloor during dive 5 of Deep Connections 2019 expedition.

A large endangered Atlantic Halibut (Hippoglossus hippoglossus) seen resting on the seafloor during Dive 05 of the Deep Connections 2019 expedition. Image courtesy of the NOAA Office of Ocean Exploration and Research, Deep Connections 2019. Download larger version (jpg, 1.5 MB).

Striped shrimp seen on a bubblegum coral during dive 5 of Deep Connections 2019 expedition.

Striped shrimp seen on a bubblegum coral during Dive 05 of the Deep Connections 2019 expedition. Image courtesy of the NOAA Office of Ocean Exploration and Research, Deep Connections 2019. Download larger version (jpg, 1.3 MB).

The remotely operated vehicle (ROV) reached the seafloor near the northern wall on the canyon, where the current was relatively swift. The floor of the canyon was predominantly soft sediment, with a similar biological assemblage as that observed at the Dive 03 site, composed of quill worms, lantern sharks, schools of fin squid, and deep-sea red crabs. Several clumps of Lophelia pertusa skeleton were observed in the bottom of the canyon with sediment displaced around them, suggesting that they fell off the northern canyon wall, but no living specimens were observed. As we traveled across the canyon axis, we observed abundant evidence of slope failure in the form of large boulders, which hosted sponges, cup corals, plexaurid corals, and Venus flytrap anemones. Upon reaching the southern wall of the canyon, we discovered sheer walls of sandstone and limestone heavily encrusted with corals, sponges, and other invertebrates. We documented three large specimens of Atlantic Halibut, an endangered species. The planned ascent up the southern canyon wall was halted to evade a suspended fishing line, and we also found other evidence of fishing gear along the bottom. Shortly after beginning our ascent along the wall, the canyon wall abruptly transitioned to a more mildly sloping, fine sediment environment, similar to the Northeast Channel dive site.

Small bobtail squid nestled between clumps of dead Lophelia pertusa seen during dive 5 of Deep Connections 2019 expedition.

Small bobtail squid nestled between clumps of dead Lophelia pertusa seen during Dive 05 of the Deep Connections 2019 expedition. Image courtesy of the NOAA Office of Ocean Exploration and Research, Deep Connections 2019. Download larger version (jpg, 1.1 MB).

Dense deep-sea coral and sponge community observed on a sheer wall during dive 5 of Deep Connections 2019 expedition.

Dense deep-sea coral and sponge community observed on a sheer wall during Dive 05 of the Deep Connections 2019 expedition. Image courtesy of the NOAA Office of Ocean Exploration and Research, Deep Connections 2019. Download larger version (jpg, 1.3 MB).

Location of Dive 5 of the Deep Connections 2019 expedition on September 2, 2019.

Location of Dive 05 of the Deep Connections 2019 expedition on September 2, 2019. Download larger version (jpg, 1.7 MB).

Map showing the dive track of dive 5 of the Deep Connections 2019 expedition.

Map showing the dive track of Dive 05 of the Deep Connections 2019 expedition. Download larger version (jpg, 391 KB).