Deep Sea Benthic Biodiversity dataset https://portal.medin.org.uk/portal/start.php?tpc=006_5423c2f9d3505bd6a17a0ee286e1d7a8 The deep sea benthic biodiversity dataset encompasses a wide range of benthic sampling and observational activities carried out by the Scottish Association for Marine Science (SAMS) since 1973. Data include analyses of samples obtained by fish trawls, benthic imagery and core sampling. The principle regions covered are the Arctic, North Atlantic and Rockall Trough and the Portuguese coast. Sampling has been carried out on numerous cruises, funded through various initiatives (ranging from NERC to commercially-funded ventures). A wide range of methods and equipment were used to obtain the information. These include Agassiz trawls, bed hop cameras, dredges, grabs, epibenthic sledges, corers and landers. Sampling of the macro and megabenthic community in the Rockall Trough (N.E. Atlantic) was primarily undertaken at two deep-sea permanent stations (54deg 40 N, 12deg 16 W in 2900m depth and 57deg 19 N, 10deg 28 W in 2200m depth) on a seasonal and interannual basis. Macrofauna samples were normally retained on 0.42mm sieves and sometimes 0.25mm. Net mesh sizes down to 0.3mm were also used. Sample processing was normally to major taxa then to family and, where possible, species groups. Partial sample processing of common echinoderms and bivalve molluscs for length/frequency/season data was carried out with most samples. Collaboration on taxonomy, where necessary, was with the Natural History Museum, London or the recognised experts in the field. These data help to build up a temporal and spatial record of regional biodiversity and consequently are a valuable tool to monitor the state of marine habitats. 20171003 20150616