Highlights: 00:25:14 Stalked crinoids 00:36:29 Hexactinellid sponges 00:42:18 Fish

This canyon is mostly comprised of soft sediment substrate. On carbonate ledges less than 2 m in height brisingids and chrysogorgiid occur. Soft sediment shows signs of bioturbation; the conspicuous fauna included stalked crinoids, echinoid species including Phormosoma placenta.

START VIDEO [00:00:00]/[16:06:00] [1] The transect starts on a relatively bioturbated gently upsloping mud bottom. Stalked crinoids (probably cf. Democrinus sp. OTU1103 which anchors in mud) protrude from the sediment and Ophiomusa lymani is frequently encountered, along with occasional other fauna. After a sparse patch of pebbles [00:13:00] [2] the crinoids are no longer seen and O. lymani dominates, including through another brief patch of sparse pebbles. [00:17:00] [3] A dense patch of Gracilechinus acutus norvegicus urchins is encountered then at [00:20:00] [4] back to O. lymani. [00:21:00] [5] carbonate rock is visible beneath the mud hosting mixed corals, transitioning back to [00:22:00] [6] O. lymani on deeper bioturbated mud. [00:23:00] [7] another G. acutus norvegicus patch. [00:23:00] [8] flat carbonate is again visible beneath the mud veneer hosting mixed corals dominated by Chrysogorgiidae sp . (OTU1008). This transitions to a carbonate step (c 50cm high), with denser corals, still Chrysogorgiidae dominating, but antipatharians, anemones, sea pens, and echinoderms (especially brisingids, stalked crinoids). The ROV traverses left along it until it shallows, before returning right and moving forward and past it over flat carbonate with mud veneer before it deepens at [00:27:00] [9] cf. Democrinus sp . and O. lymani on bioturbated mud. [00:29:00] [10] again flat then stepped/terraced carbonate with mixed corals, especially Chrysogorgiidae sp. , and a heavy mud veneer. Each step is no more than 1m high, the ROV a couple of times traverses along before proceeding over a step. The flat carbonate appears more diverse than the vertical faces here. The last terrace with mud veneer also hosts black cobbles/pebbles and one flat black boulder (resembling tarmac) with pale carbonate visible beneath. [00:40:00] [11] the mud deepens and cf. Democrinus dominates with O. lymani. [00:45:00] [12] while this assemblage continues the species most apparent becomes the pigtail coral Radicipes cf. gracilis (OTU1044), encountering one every couple of metres (see note above). [00:49:00] [13] returned to cf. Democrinus sp . /O. lymani although at [01:02:00] [14] dominance is less apparent amongst other sparse epifauna encountered (holothurians, urchins etc). Burrows here are dominant with cf. Democrinus sp . being marginally more abundant than other species. [01:07:00] [15] sparse pebbles and cobbles on mud again host mixed corals as before but caryophyllid cup corals (OTU6) are the most abundant species, together with cf. Democrinus sp . in the mud. [01:09:00] [16] the pebbles end, returning to bioturbated mud and cf. Democrinus sp., although a few Radicipes cf. gracilis are again encountered. [01:14:00] [17] Again the burrows are dominant and a couple of eucarid shrimp encountered (OTU1106) assumed to be the burrowers, with Phormosoma placenta being the dominant visible epifauna among other species. [01:15:00] [18] cf. Democinus sp . return, with frequent P. placenta [01:29:00] stopped to sample 2 pushcores before continuing until [01:46:00] [19] sparse pebbles and cobbles again host a mixed coral and sponge assemblage with no clear dominant species while cf. Democrinus sp. dominates the intermediate mud. [01:47:00] [20] cf. Democrinus sp . and Phormosoma placenta on burrowed mud, [01:51:00] [21] sparse patchy pebbles on mud with P. placenta and sparse mixed corals. At [01:51:00] steep downhill becomes visible off to the left, and the ROV proceeds over and down with this assemblage continued until END VIDEO [01:58:00]/18:05.