Marine Institute
SeaRover Dive Video

D533 Transect RB13 Mud/boulders/carbonate wall. Sea pen aggregations. Priority. Features: Fished, Escarpment. Water depth: -2210 m. TL: 1.8 km. SOL: 14° 12.938' W 55° 50.176' N

Highlights: Octopus Sea fan Brisingid starfish Orange anemone Bamboo coral & brittlestar - Ophiomusa Bamboo coral and Phelliactis anemone

The first half of this dive is flat soft sediment with little conspicuous fauna with the exception of a few anemones, including burrowing forms and Phelliactis sp., the soft coral Anthomastus sp., incirrate octopus and grenadiers. Drop stones play host to cup corals, encrusting sponges, Anthomastus sp., and the anenome Actinernus sp. The presence of a vertical chalk-like wall with mud overlay saw an increase in species richness. Here lots of brisingiids, small sponges, echinoids, ophiuroids, encrusting sponges, cup corals, Acanella sp., gorgonian fans with associated snake stars and the squat lobster Munida sp. Heavy marine snow occurred throughout this dive, making visibility poor in some areas.

START VIDEO [1] [00:00:00]/03:28The video starts with the ROV carrying out core sampling which takes place in muddy sediment on a moderate slope. Ceriantharia species are most abundant species with frequent sights of Coryphaenoides guentheri. Similar muddy sediment carries on for the first hour of the transect. [2] [01:06:00] Sparse boulders appear during this part of the transect where a small patch of sea pen aggregation (Pennatulacea indet) is present. [3] [01:13:00] Transect crosses small escarpment (overhanging carbonate mound) dominated by Brisingidae OTU274. [4] The ROV reaches a flat summit of muddy sediment dominated by Acanella arbuscula for most of the last part of the video. Between [01:45:00] and [01:57:00] the ROV collects a sample of A. arbuscula END VIDEO.

Progression Start Duration Code Name
1[00:00:02]01:04:47M.AtUA.MuAtlantic upper abyssal mud
2[01:04:50]00:07:13M.AtUA.MuAtlantic upper abyssal mud
3[01:12:04]00:15:43M.AtUA.CoAtlantic upper abyssal coarse sediment
4[01:27:48]00:28:03M.AtLB.Mu.EreCorErect coral field on Atlantic lower bathyal mud

Porifera
cf. Phakellia ventilabrum : 202 : R
Porifera encrusting sp. 1 (white) : 1 : R
Porifera globose (muddy) : 1128 : R
Porifera massive globose sp. 9 : 380 : R
Cnidaria
Cerianthidae sp. 1 : 2 : R
Actiniaria sp. 20 : 605 : R
cf. Halcampoididae sp. : 984 : R
Actinernus michaelsarsi : 554 : R
Phelliactis sp. 1 : 255 : R
Stauropathes arctica : 547 : R
Desmophyllum cf. dianthus : 335 : R
Anthomastus grandiflorus : 278 : R
Acanella arbuscula : 585 : R
Paramuricea sp. : 1050 : R

Pennatulacea (indet.) : 1114 : R
Pennatulacea sp. 3 (submerged axis) : 1191 : R
Anthoptilum sp. : 1107 : R
Arthropoda
Munida tenuimana : 339 : R
Caridea (indet.) : 1077 : R
Munidopsis sp. : 1126 : R
Eucarida sp. : 1106 : R
Mollusca
Muusoctopus johnsonianus : 1194 : R
cf. Grimpoteuthis sp. : 1176 : R
Echinodermata
Democrinus sp. : 1103 : R
Crinoidea sp. 1 : 131 : R
Ophiomusa lymani : 551 : R
Brisingidae sp. : 274 : R

Solasteridae sp. (white) : 9977 : R
Echinidae sp. (white) : 559 : R
Phormosoma placenta : 555 : R
Chordata
Synaphobranchus kaupii : 440 : R
Brosme brosme : 258 : R
Coryphaenoides guentheri : 577 : R
Lepidion cf. guentheri : 1160 : R
Lepidion eques : 249 : R
Polyacanthonotus rissoanus : 552 : R

Number of species = 36

© Marine Institute, MERC Consultants, Bernard Picton 2022