Here, we sampled five specimens of Chondrocladia and Cladorhiza as part of the Hidden Biodiversity project, using the SuperMohawk ROV on board the CCGS Amundsen. In October 2015, samples were collected from Scott Inlet and off Qikiqtarjuaq, and retrieved using a custom-built sample elevator. Samples were immediately dissected and processed for DNA and histological analyses. The analysis of these samples is currently in progress.

A remotely operated vehicle (ROV) video survey was conducted at the Saglek Bank location, at a depth of ~750 m in July 2018. The main objectives of this dive were to video-survey coral and sponge fauna on ridge at 750 m depth, and to collect coral and sponge samples. Bottom type was mainly sandy and gravel, with boulders in some parts of the transect. Corals include the solitary scleractinian Flabellum sp., soft corals (Nephtheidae), mushroom soft corals (probably Anthomastus sp.), sea pens Anthoptilum (erect and also lying on sea floor) and Halipteris finmarchica on sandy gravel bottom. Dead sea pen skeletons were also observed. Sponges include Asconema sp., Geodia sp., encrusting blue sponges (Hymedesmia sp.), and some unidentified fan-shape sponges. Among fish, we observed redfish (Sebastes spp.), small grenadiers (Family Macrouridae), and small (likely juvenile) skates (Family Rajidae). Other invertebrates include unidentified squat lobsters, sea anemones, and crabs.

A video-survey using a Super Mohawk remotely operated vehicle (ROV) was conducted in July 2017 at Lancaster Sound, Nunavut. The benthic environment was video-recorded and opportunistically photographed using a high-definition camera (1Cam Alpha, Sub C Imaging, 24.1 megapixels), at ~740 m. The ROV recorded transect data for approximately 1 km over a level muddy sand bottom with abundant Umbellula sea pens, Chondrocladia sp. carnivorous sponges, small Virgularia sp. sea pens, and common other sessile, sedentary and mobile epifauna and infauna including cerianthids, sea anemones, large Gorgonocephalus sp., and two common ophiuroid species, small holothurians and sea stars. The most common fish were eelpouts (Lycodes sp.), although several other types of fish were observed. Depth change over the 1 km transect was less than 10 m.

A remotely operated vehicle (ROV) video survey was conducted at the NE Saglek Bank location, at a depth of ~1000 m in July 2018. The main objectives of this dive were to survey epifauna at 1000 m off of the bank and to collect corals, sponges, and other large epifauna from this depth zone. This dive was aborted due to twisting of cable wire and tension which caused video to fail repeatedly. Dive ended at 982 m.

A video-survey using a Super Mohawk remotely operated vehicle (ROV) was conducted in July 2017 at Pond Inlet, Nunavut. The benthic environment was video-recorded and opportunistically photographed using a high-definition camera (1Cam Alpha, Sub C Imaging, 24.1 megapixels), starting at a depth of 850 m. Samples of corals and sponges were collected, mainly for studies of biodiversity and geochemistry. Soft corals, sponges, and sea anemones were conspicuous at this site.

The ROV dive at this site was aborted after 35 minutes underwater due to strong winds.

A remotely operated vehicle (ROV) video survey was conducted at the NE Hatton Sill location, at a depth of ~620 m in August 2018. The primary purpose of the ROV dive at this location was to obtain video-transect data for species composition determination, site characterization and depth distribution of corals and sponges, and to collect live and dead corals and sponges. Bottom type was mainly sand and gravel with occasional boulders. Semi-consolidated sand was observed at various points within the dive. Corals observed during this dive include Primnoa resedaeformis (including dead skeletons), soft corals, mushroom corals (e.g. Anthomastus sp.), Paramuricea sp., Radicipes sp., sea pens, sponges including Asconema spp. and Geodia spp.

A remotely operated vehicle (ROV) video survey was conducted at the Saglek Bank location, at a depth of ~500 m in July 2018. The primary purpose of this ROV dive was the geological and biological site characterization across depths, and sampling of dead coral skeletons, live corals for stable isotopes and lipids, and sponges for stable isotopes. Bottom type was mainly sandy gravelly bottom. Small sponges and soft corals (Family Nephtheidae) were abundant at this site (probably Geodia spp.). Other corals observed include red mushroom corals (Family Alcyoniidae, likely Anthomastus sp.), Primnoa resedaeformis (live and dead – skeletons). Primnoa resedaeformis colonies were mostly small, and abundant at certain parts of the dive. No sampling was possible during this dive due to a mix of strong currents and ROV issues.

Sponges were sampled from multiple sites in the Northeast Atlantic from multiple cruises aboard the CCGS Amundsen. Benthic sponges were obtained through Box cores, Agassiz trawls, and through targeted sampling using the SuMO ROV. Sponges were photographed on board and in-situ when possible (using ROV camera). Collected sponges were retained for taxonomic analysis. Whole or portions of each collected sponge were preserved in 96% ethanol to prevent DNA degradation. Larger sponge fragments were frozen on board. Collected sponges are to be subsampled for morphology-based taxonomy (analysis of spicule structure and body form), and for molecular taxonomy through extraction and amplification of cytochrome oxidase subunit I (COI) mitochondrial DNA fragments for DNA barcoding. In total, 112 separate sponges were sampled during the 2015/2016 leg from depths ranging between 80-1148 metres and encompassing latitudes 60°18N to 68°15N. 31 specimens were collected using the ROV and therefore have associated in-situ video imagery which will aid in species identifications and descriptions. In total, 48 separate sponges were sampled during the 2017 leg from depths between 84 - 875 metres and encompassing latitudes 62°34N to 78°19N. Nine specimens were collected using the ROV and therefore have associated in-situ video imagery which will aid in species identifications and descriptions. In-situ videos are not included in the dataset but will be made available upon request. See Links to data section for contact.