Marine Institute
SeaRover Dive Video

D537 Transect RB24 Mosaic sediment (gravel/boulders/bedrock) on slope with Lophelia/Madrepora reefs. Mud with Cidaris cidaris. Non Priority. Features: Escarpment, Ridge, Straddles SAC. Water depth: -720 m. TL: 4 km

Highlights: Lophelia & fish Sailfin roughshark - Oxynotus paradoxus Pink anemone

Rock outcrops, boulders and pebble strewn substrate with Lophelia and/or Madrepora forming large reefs in some areas. Corals are common and include Leiopathes sp. and Bathypathes sp., bamboo corals and large gorgonians, as are fish species including grenadiers, Lepidion eques, eels and monkfish. There is a variety of fan-shaped sponges along with blue and yellow encrusting sponge. A large grouper shark is observed.

START VIDEO [00:00:00]/04:21 [1] The entire transect is on mosaic sediment (mud/gravel/boulders) on moderate slope where Lophelia pertusa/Madrepora oculata colonies dominate on hard substrata and Cidaris cidaris dominate on mud. [00:01:00]. [00:16:00] From this point until the end of the transect, frequent/abundant aggregations of Phakellia ventilabrum OTU202 on boulders, at times co-dominating with L. pertusa/M. oculata colonies. [00:42:00]- ROV stops for imagery. [01:17:00] The ROV is now on top of bedrock, which is covered in mosaic sediment (mud/gravel/boulders). L. pertusa/M. oculata colonies dominate on hard substrata while C. cidaris dominates on mud. [01:23:00] Now no more bedrock. Mud/gravel/boulders continue. [01:25:00]-[01:30:00] ROV stops for one pushcore sample. The ROV moves a little bit further until [01:33:00]-[01:41:00] ROV stops for pushcore sampling and imagery. [01:45:00] ROV stops for sampling, although sampling aborted. In this part of the transect, boulders are less abundant as well as C. cidaris. [01:57:00] ROV stops again for sampling/sampling aborted. END VIDEO [02:00:00]/06:21.

Eels were present (at times abundant) throughout the entire transect. An individual of Centrophorus squamosus was observed, also another small Elasmobranchia species was encountered (possibly Centrophorus sp.).

Progression Start Duration Code Name
1[00:00:00]01:16:11M.AtMB.Bi.CorRee.LopFraMixed coral assemblage on Atlantic mid bathyal Lophelia pertusa reef framework (biogenic structure)
2[01:16:12]00:06:08M.AtMB.Ro.MixCorMixed cold water coral community on Atlantic mid bathyal rock and other hard substrata
3[01:22:21]00:36:21M.AtMB.MxAtlantic mid bathyal mixed sediment

Porifera
cf. Farreidae : 1142 : R
cf. Phakellia ventilabrum : 202 : F
cf. Polymastia penicillus : 1137 : R
Geodia barretti : 196 : R
Porifera branching-erect sp. 1/Antho dichotoma : 281 : R
Porifera encrusting globose (pale) : 75 : R
Porifera encrusting green : 802 : O
Porifera encrusting sp. 14 : 52 : R
Porifera encrusting sp. 15 (yellow) : 58 : R
Porifera lamellate lobose : 81 : R
Porifera massive globose sp. 6 : 137 : R
Blue Porifera encrusting : 800 : R
Cnidaria
Cerianthidae sp. 1 : 2 : R
Pachycerianthus multiplicatus : 458 : R
Actiniaria sp. 20 : 605 : R
Actinernus michaelsarsi : 554 : R
Bolocera tuediae : 12 : R
Phelliactis sp. 1 : 255 : R
Antipathes dichotoma : 1187 : R
Stichopathes cf. gravieri : 283 : R
Stichopathes sp. : 560 : R
Leiopathes sp. : 305 : O
Bathypathes sp. (brown) : 284 : O
Parantipathes sp. (branched) : 1161 : R

Caryophyllia sp. 2 : 6 : O
Lophelia pertusa : 250 : F
Madrepora oculata : 251 : O
Anthomastus grandiflorus : 278 : R
cf. Clavulariidae sp. : 289 : R
Eknomisis sp. : 649 : R
Keratoisis sp. 2 : 578 : R
Paramuricea sp. : 1050 : R
Gorgonacea sp. 7 (pink) cf. Isidella : 307 : R
Pennatula aculeata : 1046 : R
Hydrozoa (flat branched) : 56 : R
Rhodaliidae sp. 1 : 950 : R
Annelida
Serpulidae sp. 1 : 106 : R
Arthropoda
Chirostylidae sp. 1 (indet.) : 285 : R
Paromola cuvieri : 304 : R
Caridea (indet.) : 1077 : R
Munidopsis sp. : 1126 : R
Mollusca
Muusoctopus johnsonianus : 1194 : R
Margarites sp. 1 : 277 : R
Echinodermata
Crinoidea sp. 1 : 131 : R
Crinoidea sp. 1 : 131 : R
Gorgonocephalus sp. 1 : 214 : R

Brisingidae sp. : 274 : R
Pseudarchaster sp. 1 : 433 : R
Ceramaster/Peltaster/Plinthaster sp. 1 : 234 : R
Echinidae sp. (pink) : 194 : R
Cidaris cidaris : 211 : O
Araeosoma fenestratum : 188 : R
Parastichopus tremulus : 266 : R
Chordata
Centrophorus squamosus : 1048 : R
Oxynotus paradoxus : 9984 : R
Squaliformes sp. : 569 : R
Chimaera monstrosa : 265 : R
Synaphobranchus kaupii : 440 : R
Merlangius melangus : 1019 : R
Coryphaenoides guentheri : 577 : R
Macrouridae sp. (cf. Coelorhynchus) : 1172 : R
Lepidion cf. guentheri : 1160 : R
Lepidion eques : 249 : R
Phycis blennoides : 1020 : R
Lophius piscatorius : 273 : R
Helicolenus dactylopterus : 227 : R

Number of species = 66

© Marine Institute, MERC Consultants, Bernard Picton 2022