Marine Institute
SeaRover Dive Video

D556 Transect PB14 Mosaic substrata with with soft corals, crinoids and Brisinga on hard substrate. Priority. Features: Very deep rise. Water depth: -2900 m. TL: 2.8 km SOL: 15° 16.765' W 51° 38.467' N

Highlights: Brisingid starfish Stalked barnacles Bamboo coral Brisingid starfish & bamboo coral Bamboo coral & sponges Sea fan

Soft sediment with black stones and rocks. Chrysogorgiids, brisingiids and small sponges associated with rocks. Large waves of barnacle hash with low densities of elpidiids and asteroids cover areas of sediment. Steep rocky incline with black drop stones, crinoids, sponges, chrysogorgiid, Bathypathes and brisingiids. Species to note unknown black coral (sampled).

VIDEO A STARTS AT [00:00:00]/17:25. Thick marine snow throughout the whole transect. [1] Muddy/sperse pebbles/cobbles with Brisingidae. Mainly sparse epifauna. [00:05:00] [2] Here carbonate horizontal ledges/carbonate slope on gentle slope; though mud/cobble/pebble continue. [00:10:00] [3] Here rippled sand start to predominate on steep uphill. [00:21:00] Pebble fields become more frequent. [00:22:00] [4] Sand mixed with pteropod hash is abundant. [00:29:00] [5] Now rippled sand/gravel sediment. [00:30:00] [6] Sand/pteropod hash frequently recorded with occasional cobbles/boulders. [00:45:00] [7] Sand/pteropod hash/pebble/cobble/boulder. Sparse epifauna including glass sponges, starfish and Chrysogorgiidae sp.1. [00:46:00]-[00:50:00] ROV stops for imagery of Chrysogorgiidae sp.1 OTU1008. [01:18:00] [8] Gravel/pebble/cobbles with dominant sea urchin OTU1129 and frequent stalked crinoids Anachalypsicrinus nefertiti OTU1031. [01:41:00] Exposed rock crust. [01:45:00]-[01:47:00] ROV stops for imagery of Isididae sp OTU1064. [01:56:00] Now soft bedrock exposed/pebbles/cobbles with dominant stalked crinoids Anachalypsicrinus nefertiti OTU1031. VIDEO A ENDS 19:22.

VIDEO B STARTS [01:57:00]/19:24. [9] Stalked crinoids, feather stars and Brisingidae OTU274 dwelling on pebble/cobble/boulder up slope. Marine snow is present in this dive. [01:59:00] ROV approaches the edge of this flat/gentle slope where geormophological features include exposed soft boulders and vertical edges, as well as dense cobble/boulder fields. Brisingidae OTU274 is frequent. [02:00:00] [10] Vertical soft boulders/bedrock surrounded by pebble/cobble fields. Brisingidae and Koehlermetra porrecta are occasionally/frequently encountered. [02:02:00] ROV is moving 45 degrees to the left, leaving the edge of the bedrock and going upslope. [11] Pebble/cobble/boulder continue in this part of the transect. Ophiomusa lymani OTU551 is dominant. [02:04:00] [12] ROV reaches the edge of the slope with soft corals and stalked crinoids hanging from the edge. Then the ROV descends on a lower level where sediments are predominantly pebble/cobble/boulder. On boulders, encrusting sponges, Chrysogorgiidae sp.1 and Hydrozoa co-dominate. [02:07:00]-[02:12:00] ROV stops for imagery of Chrysogorgiidae sp.1 and encrusting sponges. [02:14:00] [13] Dense pebble/cobble fields with dominant A. nefertiti. [02:17:00]-[02:25:00] ROV stops for imagery of Stauropathes sp. 3. [02:40:00] [14] Soft bedrock exposed with pebble/cobble fields. A. nefertiti and K. porrecta co-dominate. [02:54:00] Cable on the seafloor. [02:57:00] ROV samples one pushcore until VIDEO B ENDS [03:01:00]/20:28.

Progression Start Duration Code Name
1[00:00:00]00:04:46M.AtUA.MuAtlantic upper abyssal mud
9[00:00:00]00:03:11M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
10[00:03:12]00:02:05M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
2[00:04:47]00:05:31M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
11[00:05:18]00:02:39M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
12[00:07:58]00:09:43M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
3[00:10:19]00:12:35M.AtUA.MuAtlantic upper abyssal mud
13[00:17:42]00:25:36M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
4[00:22:55]00:07:17M.AtUA.SaAtlantic upper abyssal sand
5[00:30:13]00:01:03M.AtUA.SaAtlantic upper abyssal sand
6[00:31:17]00:16:25M.AtUA.SaAtlantic upper abyssal sand
14[00:43:19]00:20:54M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
7[00:47:43]00:33:16M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
8[01:21:00]00:36:00M.AtUA.RoAtlantic upper abyssal rock and other hard substrata

Porifera
Stylocordyla borealis : 1212 : R
Porifera cylindrical sp. 2 : 1075 : R
Porifera encrusting sp. 1 (white) : 1 : R
Porifera encrusting sp. 18 (cream) : 105 : R
Porifera lamellate (bubbles) : 1156 : R
Porifera lamellate lobose : 81 : R
Porifera lamellate sp. 7 : 422 : R
Porifera massive lobose sp. 32 : 1090 : R
Cnidaria
Actiniaria sp. 20 : 605 : R
Actinernus michaelsarsi : 554 : R
Bathypathes sp. (brown) : 284 : R
Bathypathes sp. 1 : 328 : R
Stauropathes arctica : 547 : R
Stauropathes sp. 3 : 1208 : R
Caryophyllia sp. 2 : 6 : R
Anthomastus grandiflorus : 278 : R
cf. Chrysogorgiidae sp. : 1200 : R

Chrysogorgidae sp. 1 : 1008 : O
Isididae sp. (fine branching) : 1064 : R
Umbellula sp. : 581 : R
Hydrozoa (flat branched) : 56 : R
Arthropoda
Galacantha sp. : 1144 : R
Bathynectes sp. : 235 : R
Eucarida sp. (red deep) : 1138 : R
Bryozoa
Reteporella sp. : 204 : R
Echinodermata
Koehlermetra porrecta : 315 : R
Anachalypsicrinus nefertiti : 1031 : R
Crinoidea sp. : 1072 : R
Ophiomusa lymani : 551 : R
Brisingidae sp. : 274 : F
Pseudarchaster sp. 1 : 433 : R
Pterasteridae sp. : 1115 : R
Asteroidea (cf. Ceramaster/Hymenaster, red/pink)"" : 1173 : R

Asteroidea cf. sp. inulosida : 1186 : R
cf. Echinus (deep pink spine) : 1129 : R
Echinothuroidea sp. : 1094 : R
cf. Amperima sp. : 628 : R
Mesothuria intestinalis : 536 : R
Holothuroidea sp. (pink deep) : 1179 : R
Chordata
Nezumia aequalis : 1003 : R
Coryphaenoides guentheri : 577 : R
Lepidion cf. guentheri : 1160 : R
Mora moro : 349 : R
Phycis blennoides : 1020 : R
Notacanthiformes sp. 1 : 1012 : R

Number of species = 45

© Marine Institute, MERC Consultants, Bernard Picton 2022