Marine Institute
SeaRover Dive Video

D548 Transect PB03 Rippled sand/boulders/carbonate wall with mainly crinoid colonies. Priority. Features: Ridge, Wall. Water depth: -2350 m. TL: 2.7 km SOL: 15° 2.550' W 53° 14.543' N

Highlights: Compass anemone Purple sea cucmber Sea pen

Areas of rippled sand, shell hash and carbonate sediment form the main substrate with a vertical carbonate cliff towards the end of the dive. Shell hash is very dense in some areas with little faunal associations. Sea pens, holothurians and echinoid urchins are observed throughout. Hard substrate, carbonate sediment and cliffs are species poor consisting of crinoids, glass sponges, the occasional cup coral and ophiuroids. Fish abundance and diversity are also low, the occasional grenadier, eel and Alepocephalidae spp.

START VIDEO A [00:00:00]/01:01. The entire dive is set on moderate slope interspersed with carbonate vertical walls. [00:00:00]-[00:24:00] ROV stops for sampling a pushcore. [1] Rippled sand/pteropod hash on uphill slope with frequent pebbles and cobbles. Sparse epifauna, mainly Paguridae sp. with Adamsia sp. and Brisingidae. [00:28:00] [2] Now the ROV reached the bottom of carbonate vertical wall and slowly moves upwards. [3] Sediment predominantly sand and cobbles. [4] Broken carbonate rocks with inlets are frequent where mainly stalked crinoids dwell. From vertical wall to narrow sandy ledges are recorded in this part of the transect. [00:34:00] [5] The ROV reaches the top on the ledges where rippled sand sediment dominate. Sparse epifauna , including Ophiomusa lymani. [00:37:00] [6] Pebbles sediment on sand with stalked crinoids Bathycrinidae sp. [00:39:00] [7] Carbonate boulders and rocks from this point. Scarce and sparse epifauna, including Bathycrinidae sp. and glass sponges. [00:42:00] [8] now again rippled sand. [00:45:00] [9] now boulders/cobbles on rippled sand. [00:46:00]-[00:57:00] ROV stops for sampling of Actiniaria sp.18. [01:02:00]-[01:04:00] ROV stops for imagery of Benthothuria sp. [01:18:00] [10] Sediment is now covered in pteropod hash and a few Galacantha sp. are encountered. [01:54:00] [11] Now carbonate boulders on ripple sand and pebbles with crinoids and glass sponges. [01:56:00] [12] ROV climbs again a vertical carbonate wall with Bathycrinidae sp. hanging from the wall. The peculiarity of the wall is the presence of crevices and small inlets. [01:58:00] [13] The ROV reaches the top of the wall. Again rippled sand on steep hill. [01:59:00] [14] Carbonate crust/cobbles/pebbles/rippled sand with abundant Bathycrinidae sp. END VIDEO A [02:01:00].

START VIDEO B [02:01:00]. The second tape shows predominantly rippled sand and pebble/ cobble fields. Throughout the dive, moderate slope interspersed with vertical walls. Vertical walls mainly characterized by carbonate. Bathycrinidae sp. is the only dominant epibenthic species to record. END VIDEO [02:42:00]/03:43.

Progression Start Duration Code Name
1[00:00:00]00:27:14M.AtUA.SaAtlantic upper abyssal sand
15[00:00:00]00:10:00M.AtUA.SaAtlantic upper abyssal sand
16[00:10:01]00:05:22M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
17[00:15:24]00:06:39M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
18[00:22:04]00:03:30M.AtUA.SaAtlantic upper abyssal sand
19[00:25:35]00:16:47M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
2[00:27:15]00:01:26M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
3[00:28:42]00:00:55M.AtUA.SaAtlantic upper abyssal sand
4[00:29:38]00:03:24M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
5[00:33:03]00:02:50M.AtUA.SaAtlantic upper abyssal sand
6[00:35:54]00:02:29M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
7[00:38:24]00:02:56M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
8[00:41:21]00:02:52M.AtUA.SaAtlantic upper abyssal sand
9[00:44:14]00:32:46M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
10[01:17:01]00:37:04M.AtUA.SaAtlantic upper abyssal sand
11[01:54:06]00:02:25M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
12[01:56:32]00:02:06M.AtUA.RoAtlantic upper abyssal rock and other hard substrata
13[01:58:39]00:00:57M.AtUA.SaAtlantic upper abyssal sand
14[01:59:37]00:00:23M.AtUA.RoAtlantic upper abyssal rock and other hard substrata

Porifera cylindrical sp. 2 : 1075 : R
Porifera encrusting sp. 2 : 7 : R
Porifera globose lobose : 1178 : R
Porifera lamellate (escarpment) : 1101 : R
Porifera lamellate sp. 7 : 422 : R
Actiniaria sp. 1 : 4 : R
Actiniaria sp. 18 : 582 : R
Adamsia sp. : 1066 : R
Anthomastus grandiflorus : 278 : R
Anthoptilum sp. : 1107 : R
Umbellula sp. : 581 : R
Galacantha sp. : 1144 : R

Paguridae sp. : 205 : R
Colossendeis sp. 1 : 1059 : R
Eucarida sp. (red deep) : 1138 : R
Colus sp. : 113 : R
Bathycrinidae sp. : 1141 : R
Bathycrinidae sp. 1 : 1041 : R
Bathycrinidae sp. 2 cf. Porphyrocrinus thalassae : 1045 : R
Anachalypsicrinus nefertiti : 1031 : R
Crinoidea sp. 1 : 131 : R
Ophiomusa lymani : 551 : R
Ophiuroidea sp. (orange deep) : 646 : R
Brisingidae sp. : 274 : R
Ceramaster/Peltaster/Plinthaster sp. 1 : 234 : R

cf. Echinus (deep pink spine) : 1129 : R
Echinoidea sp. 5 : 572 : R
Peniagone sp. : 1167 : R
Mesothuria intestinalis : 536 : R
Benthothuria sp. : 1124 : R
Coryphaenoides guentheri : 577 : R
Lepidion cf. guentheri : 1160 : R
Mora moro : 349 : R
Halosauridae sp. : 1113 : R
Polyacanthonotus rissoanus : 552 : R

Number of species = 35

© Marine Institute, MERC Consultants, Bernard Picton 2022