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.

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.

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.

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.

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.

These data are gonad index (gonad mass/total animal mass) and egg size measurements for two Antarctic marine invertebrates, the starfish Odontaster validus and the brittle star Ophionotus victoriae. Data are for samples hand-collected monthly, where weather permits, by scuba divers from sites near the British Antarctic Survey''s research station at Rothera Point, Adelaide Island. Samples were first collected in 1997 and have continued for 19 years to 2015.

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.

Transcriptomic analyses were undertaken on both in situ collected and experimentally warmed blue mussels (Mytilus edulis) from Greenland. M. edulis were collected from the Godthabsfjorden near Nuuk, Greenland (64.45555, -51.14416) at the following locations and dates: Inner fjord (64.45941, -50.31030) on 11/06/2018; outer fjord (64.19666, -51.69) on 13/06/2018, and sub-tidal (64.19666, -51.69) on 13/06/2018 (outer fjord at 20-40cm below the lowest low water mark). The in situ collected inner and outer fjord intertidal animals with outer fjord subtidal animals used as controls were collected at 27 degree Celsius, 19 degree Celsius and 3 degree Celsius, respectively. Some of the outer fjord subtidal M. edulis were experimentally warmed to 22 degree Celsius and 32 degree Celsius for one hour to mimic high aerial exposure temperatures in the inner and outer fjord intertidal, respectively. RNA-Seq was performed on 5 animals for each treatment, with all subsequent bioinformatics analyses performed by Novogene, China. This work was supported by the Carlsberg Foundation, the Independent Research Fund Denmark (Danmarks Frie Forskningsfond) (DFF-International Postdoc; case no. 7027-00060B), a Marie Sklodowska-Curie Individual Fellowship (IF) under contract number 797387 and Aage V. Jensens Fond (Aage V. Jensens Foundation) and NERC-UKRI core funding to the British Antarctic Survey.

This dataset is referring to 1-year time series of particle flux, as measured by a shelf moored sediment traps (WCB) located in the Southern Ocean (northern Scotia Sea sector), a globally important region of atmospheric CO2 drawdown. This sector holds >50% of the circumpolar krill stock of Antarctic krill and is the geographic focus for the krill fishing industry. The dataset includes the specific contribution of krill components to the total C flux parameters (such as exuviae, faecal pellets and carcasses) within a period from January to December 2018. Values of krill seasonal standing stock estimated from krill standard lengths is also included in the dataset. The dataset allow the quantification of the relevant contribution of krill to the POC flux. Since abundance of Krill around South Georgia is environmentally influenced, the dataset highlights the sensitivity of POC flux to rapid regional environmental change.