Deep-Sea holothurians (Echinodermata, Holothuroidea) of the Colombian Southern Caribbean Sea

Study Extent

Southern Colombian Caribbean

Sampling

Survey areas of interest were assessed using 25 towed camera transects. These transects registered seafloor features, during 3-hour surveys, taking still images every 20 seconds. Benthic and pelagic megafauna specimens were recorded in the images.

Quality Control

Videos were analysed twice for the presence of cnidarians by two different experts. This methodology allowed us to ensure all cnidarians were registered. Still images and pictures of towed camera were analysed twice by the same expert, who did preliminary identification to phylum and class. All sea cucumber images were then identified to the lowest possible. When in doubt about the identification, additional experts were contacted and the images were sent to them in jpg format for towed camera photographs, and as a snapshot (also in jpg format) for ROV videos.

Method steps

1. ROV surveys: a total of 48 video transects (duration: 9 h 9 min 26 sec) were used, looking for benthic and pelagic sea cucumbers. Snapshots were taken for each sea cucumber, registered coordinates and depth and identified them to the lowest possible taxonomic level. Towed camera images: A total of 5,066 photographs, looking for benthic and pelagic sea cucumbers were analyzed. For each sea cucumber, coordinates and depth were registered and identified to the lowest possible taxonomic level.

Southwestern Colombian Caribbean, ultra-deep waters