KRILLBASE is a data rescue and compilation project which aims to improve the availability of information on two of the Southern Ocean''s most important zooplankton taxa: Antarctic krill (Euphausia superba) and salps (Family Salpidae). In 2016, the project released a database of information from 15,194 scientific net hauls, collected between 1926 and 2016 by scientists from ten countries. These data, on the density of Antarctic krill and salps, provide a resource for analysing the distribution and abundance of these taxa throughout the Southern Ocean, to support ecological and biogeochemical research as well as fisheries management and conservation. The data are available as a downloadable csv files and via a seachable web interface. Each row of the main data table represents either a net haul or a composite of several net hauls. The columns describe searchable and filterable sampling and environmental information as well as the krill and salp density. The krill data are presented as both the observed density (NUMBER_OF_KRILL_UNDER_1M2, no.m-2) and the density standardised to a single, relatively efficient sampling method (STANDARDISED_KRILL_UNDER_1M2, no.m-2). The salp data are presented as observed density for all species combined, where an individual can be either a solitary oozoid or a member of an aggregate chain (NUMBER_OF_SALPS_UNDER_1M2, no.m-2). 12,758 of the net hauls in the database include krill data, 9,726 include salp data. 7,295 of the net hauls include both krill and salp data. For hauls where data for either salps or krill were not available the relevant field is blank. The RECORD_TYPE column distinguishes between four types of record and we emphasise that every analysis of the data should first screen on this field to avoid using the same data twice. Most records are labelled "haul", and these result from a single net sampling the water column at a specific station. Others, labelled "stratified pooled haul", are the combined result of several (typically three) stratified hauls (labelled "stratified haul") sampling different parts of the water column. A small number of records, labelled "survey mean" represent the arithmetic mean densities from multiple stations as this was the only recoverable information from the relevant surveys, which were mainly conducted in the 1980s. The dataset is fully described in the following publication which should be cited in published analyses of these data: Atkinson A, Hill SL, Pakhomov E, Siegel V, Anadon R, Chiba S, Daly KL, Downie R, Fielding S, Fretwell P, Gerrish L, Hosie GW, Jessopp MJ, Kawaguchi S, Krafft BA, Loeb V, Nishikawa J, Peat HJ, Reiss CS, Ross RM, Langdon B Quetin, Schmidt K, Steinberg DK, Subramaniam RC, Tarling GA, Ward P (2017) KRILLBASE: a circumpolar database of Antarctic krill and salp numerical densities, 1926-2016. Earth Syst. Sci. Data, 9: 193-210 (doi:10.5194/essd-9-193-2017)

Quantification of interactive effects of ocean warming and ocean acidification based on near-future climate change projections on morphometrics and oocyte size of benthic invertebrates (the bivalves Astarte crenata and Bathyarca glacialis) from the Western Barents Sea. Supported by The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems project (NE/N015894/1 and NE/P006426/1, 2017-2021), Natural Environment Research Council (NERC) in the UK.

Images of histological sections of oocytes to quantify oocyte size frequency distributions in Astarte crenata and Ctenodiscus crispatus used in the analyses by Reed et al. 2021 (Ecology and Evolution) from the Western Barents Sea during summer 2017 across a North - South transect intersecting the polar front. Supported by The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems project (NE/N015894/1 and NE/P006426/1, 2017-2021), Natural Environment Research Council (NERC) in the UK.

Quantification of morphological and reproductive traits in Astarte crenata and Ctenodiscus crispatus (oocyte size/gonad index), used in the analyses by Reed et al. 2021 (Ecology and Evolution) from the Western Barents Sea during summer 2017 across a North - South Transect intersecting the polar front.

Images of histological sections of oocytes to quantify the interactive effects of ocean warming and ocean acidification based on near-future climate change projections on oocyte size frequency distributions of benthic invertebrates (the bivalves Astarte crenata and Bathyarca glacialis) from the Western Barents Sea. Supported by The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems project (NE/N015894/1 and NE/P006426/1, 2017-2021), Natural Environment Research Council (NERC) in the UK.

This dataset contains data from a study of pteropod shell dissolution on individuals exposed to CO2-enriched seawater. The data include the amount of dissolution as well as the physical and chemical parameters on which carbonate chemistry parameters were calculated.

This dataset contains reflectance spectra measurements of Antarctic krill (Euphausia superba) that were sampled from the Scotia Sea in the Southern Ocean. Reflectance measurements were made on board on freshly caught krill, using a spectroradiometer. A number of these reflectance experiments were carried out across different regions of the Scotia Sea, on male, female and juvenile krill. Reflectance measurements are given for krill in both in situ and filtered seawater, as well as for water without krill. Data are presented in terms of remote sensing reflectance (Rrs). Funding for the work was primarily through a bursary awarded to Anna Belcher from Antarctic Science Ltd. Additionally, funding from the BAS ecosystems programme supported the project. The Natural Environment Research Council Field Spectroscopy Facility (NERC FSF) loaned the equipment required to carry out this research.

In 2018 RRS James Clark Ross investigated the marine benthic biodiversity of the Prince Gustav Channel area and the macrobenthic molluscan fauna collected by epibenthic sledge (EBS) has been assessed for species richness, abundance and assemblage composition as well as for functional traits. In total 20,307 mollusc specimens assigned to 50 morphospecies and 4 classes (Solenogastres, Bivalvia, Gastropoda and Scaphopoda) were identified. Assemblage analyses across the Prince Gustav Channel area did not show apparent pattern or separation across depth, taxon or station. To set the bivalve dataset into a wider context, unpublished bivalve species richness and abundance data from EBS collected stations in the area influenced by the Weddell Gyre were added. This doi dataset provides data for 1) PGC EBS locations, 2) PGC EBS molluscan abundances, 3) PGC molluscan functional traits, 4) Weddell Gyre EBS stations (300 - 2000 m depth), 5) Weddell Gyre EBS bivalve standardised 1000 m trawl length abundances (300 - 2000 m depth). Funding was provided by NERC urgency grant NE/R012296/1 ''Benthic biodiversity under Antarctic ice-shelves - baseline assessment of the seabed exposed by the 2017 calving of the Larsen-C Ice Shelf''.

In 2008 RRS James Clark Ross investigated the marine benthic biodiversity in Amundsen Sea and in 2018 the marine benthic biodiversity of the Prince Gustav Channel (PGC) area and the macrobenthic cumacean fauna (Peracarida, Crustacea) collected by epibenthic sledge (EBS) has been assessed for species richness, abundance and assemblage composition. In total 4431 cumacean specimens assigned to 58 morphospecies and 5 families were identified. To set the cumacean dataset into a wider context, published cumacean species richness and abundance data from EBS collected stations in the Magellan Region and Southern Ocean (Rehm et al 2007, Muehlenhardt-Siegel 1999, Cordoba & San Vincente 2009) were added. This dataset provides data for 1) Amundsen Sea and PGC EBS locations, 2) Amundsen Sea and PGC EBS cumacean abundances, 3) Magellan Region and Southern Ocean EBS cumacean standardised 1000 m trawl length abundances (175 - 3500 m depth). Funding for the expeditions and KL was provided by NERC NC Science for the BAS core project BIOPEARL and for NERC urgency grant NE/R012296/1 ''Benthic biodiversity under Antarctic ice-shelves - baseline assessment of the seabed exposed by the 2017 calving of the Larsen-C Ice Shelf''. Funding for DD was provided by the Deutsche Forschungsgemeinschaft grant Br1121/51-1.

Acoustic backscatter data were collected on board the RRS James Clark Ross (cruise JR161) as part of the Discovery 2010 programme. Data were collected using a Simrad EK60 echo sounder at 38, 120 and 200 kHz. The EK60 was run continuously from Stanley (Falkland Islands) to Signy (South Orkney Islands), then to South Georgia across the Scotia Sea in the austral spring (October - December) of 2006. Dedicated acoustic transects were also run at eight stations within these transects. The EK60 was calibrated prior to data collection on a previous cruise (JR159 on 13-14th October 2006). More information about the calibration can be found in the Cruise Report for JR159: https://www.bodc.ac.uk/data/information_and_inventories/cruise_inventory/report/jr152_jr159.pdf JR161 was the first of three cruises which comprise the field studies of the British Antarctic Survey''s (BAS) core science Discovery 2010 programme, funded by the Natural Environment Research Council.