The Antarctic food webs represent two entire above-belowground communities from Signy Island Reference Sites on Signy Island, one of the South Orkney Islands in the Maritime Antarctic. The two communities are a dry moss community (Antarctic dry tundra) and a wet moss community (Antarctic wet tundra). These two communities were the focus of intensive biological study by personnel from the British Antarctic Survey over the course of a decade in the 1970''s, of which the results were finally compiled into a meta-analysis by Davis (1981). The Jacobians of the dry and wet tundra were calculated by Neutel and Thorne (2014) using the empirical biomass and flow data of the respective systems from Davis'' analysis. The Jacobians represent the interaction strengths of the species in the two food webs, evaluated at equilibrium.

Calanus hyperboreus dominates the copepod biomass in the high Arctic. It forms an important intermediate trophic level in the Central Arctic food web, grazing on algae and protists and serving as prey for a large range of other zooplankton, fish and seabirds. Their unique lipids (20:1, 22:1 fatty acids and fatty alcohols) can be traced within the Arctic megafauna from seals to whales and polar bears, as these energy-rich lipids are crucial body reserves for the dark season. During the MOSAiC expedition in the Central Arctic Ocean (CAO, 2019-2020), C. hyperboreus adult females (AF) and subadult copepodites stages (CV) were sampled weekly to fortnightly. A range of nets were used to sample either horizontally underneath the sea ice or vertically from maximum 2000 m through the water column. Onboard, ~10 AF and ~20 CV of C. hyperboreus were sorted from each catch, photographed, rinsed with freshwater to remove salt and frozen at -80C for subsequent analysis of their total dry mass (DM), lipid content and a suite of trophic markers, including bulk stable isotopes (BSI), phytosterols (PS), total fatty acids (TFA), total fatty alcohols (TFAlc), and highly-branched isoprenoids (HBI). During the time of their seasonal descent at the end of summer, vertical sampling of C. hyperboreus was intensified and additional parameters were analysed, e.g. the FA and FAlc composition of their storage lipids (neutral lipids, NLFA, NLFAlc) and membrane lipids (polar lipids, PLFA, PLFAlc), the carbon isotopic composition of key FA and FAlc (CSIA-FA; CSIA-FAlc), and the tissue density. By combining this array of trophic markers, valuable information about the body conditions and feeding history of these copepods can be linked to their life cycle and vertical distribution. The initial separation of the various trophic markers was carried out at the University of Plymouth. After estimating the total DM, subsamples for BSI were sent to the Littoral, Environment and Societies Joint Research Unit stable isotope facility (CNRS - University of La Rochelle, France) for analysis. Three internal standards were added to the samples used for lipid analysis to quantify the TFA, TFAlc, PS and HBI content. As a first step, the total lipid content of the animals was extracted in dichloromethane : methanol. The lipid samples were split into two equal subsamples, one was sent to the Alfred-Wegener-Institute (AWI) in Bremerhaven/Germany for FA and FAlc analyses and the second was used for PS and HBI analyses in Plymouth. This dataset is linked to a manuscript that compares the trophic marker composition of C. hyperboreus from the surface vs. deep ocean to understand drivers, benefits, and risks of their seasonal migration in the CAO. The manuscript focusses mainly on the copepod descent in late summer and the changes in body conditions and trophic marker composition over the winter months. Contributions by KS were funded by the UK''s Natural Environment Research Council MOSAiC Thematic project SYM-PEL: "Quantifying the contribution of sympagic versus pelagic diatoms to Arctic food webs and biogeochemical fluxes: application of source-specific highly branched isoprenoid biomarkers" (NE/S002502/1). CJA, RGC, CEG, KMS and RJ were funded by the US National Science Foundation Office of Polar Programs (OPP-1824447 and OPP-1824414).

The soil food webs in this collection represent a total of 32 belowground communities studied by Neutel et al. (2007), from two natural successions in sandy dune soils: one on the Waddensea Island of Schiermonnikoog in the north of the Netherlands and the other at Hulshorsterzand, on the Veluwe, in the central Netherlands. The study sites, which constitute the two gradients, represent four consecutive stages in chronosequences of early primary vegetation succession, increasing in aboveground and below-ground productivity. The Jacobians of the 32 food webs (two series, four stages with four replicates per stage) were calculated by Neutel et al. (2007) from observed average biomass data of the respective systems, and inferring steady-state biomass flow data using a procedure described by Hunt et al. (1987). The Jacobians represent the interaction strengths of the species in the two food webs, evaluated at equilibrium.

The soil food webs in this collection represent seven belowground communities from native and agricultural soils. The seven communities are from experimental research sites in the USA, Sweden and the Netherlands. The Jacobians of the seven food webs were calculated by de Ruiter et al. (1995) using the empirical biomass data of the respective systems, and inferring steady-state biomass flow data using a procedure described by Hunt et al. (1987), see further references below. The Jacobians represent the interaction strengths of the species in the two food webs, evaluated at equilibrium.

This dataset comprises Argos PTT data for Adelie penguins, Pygoscelid adeliae, at Signy, Powell and Laurie Islands, part of the South Orkney Islands, between December and January 1999-2014. Tags were deployed across the South Orkney Islands (Signy Island, Powell Island and Laurie Island) between December and January (austral summer). The tracking data encompasses the breeding and post-breeding migratory dispersal of chinstrap penguins. The data includes coordinates for satellite uplinks for each tag and respective trip, along with error values for each satellite uplink. Metadata includes additional information about nesting and morphology, when available. PTT tags were deployed by British Antarctic Survey (BAS) personnel and supported by Natural Environment Research Council (UK) core funding and WWF grant GB095701

This dataset comprises Platform Terminal Transmitter (PTT) data for chinstrap penguins at Signy, Laurie and Monroe Islands, part of the South Orkney Islands, between December and February 2000-2016 (austral summer). The tracking data encompasses the breeding and post-breeding migratory dispersal of chinstrap penguins. The data includes coordinates for satellite uplinks for each tag and respective trip, along with error values for each satellite uplink. Metadata includes additional information about nesting and morphology, when available. PTT tags were deployed by British Antarctic Survey (BAS) personnel supported by Natural Environment Research Council (UK) core funding, WWF Grant (GB095701), Darwin Plus grant DPLUS054 and CCAMLR special fund.

This dataset comprises Global Positioning System (GPS) data for Adelie penguins, Pygoscelid adeliae, at Signy Island, South Orkneys Islands, from December 2011 to January 2016 (austral summer). Adelie penguins were fitted with GPS tags at Signy Island to better understand their movement for seabird conservation and management. This data includes GPS positions at specified intervals for deployed tags, with additional metadata on the morphology of the birds, their deployment and breeding. Work was carried out by personnel at the British Antarctic Survey (BAS) and was funded by Natural Environment Research Council (UK) core funding to BAS.

This dataset comprises Time-Depth Recorder (TDR) tracks for Adelie penguins, pygoscelid adeliae, at Signy Island, South Orkneys Islands, from December 2011 to January 2016 (austral summer). Adelie penguins were fitted with TDR tags at Signy Island to better understand their movement for seabird conservation and management. The data includes temperature and pressure at specified intervals for deployed tags, with additional metadata on the morphology of the birds, their deployment, and breeding. Work was carried out by personnel at the British Antarctic Survey (BAS) and was funded by Natural Environment Research Council (UK) core funding to BAS.

This dataset comprises Time-Depth Recorder (TDR) tracks for gentoo penguins, Pygoscelid papua, at Signy Island, South Orkneys Islands, from December 2011 to January 2016 (austral summer). Gentoo penguins were fitted with TDR tags at Signy Island to better understand their movement for seabird conservation and management. The data includes temperature and pressure at specified intervals for deployed tags, with additional metadata on the morphology of the birds, their deployment, and breeding. Work was carried out by personnel at the British Antarctic Survey (BAS) and was funded by Natural Environment Research Council (UK) core funding to BAS.

This dataset comprises Time-Depth Recorder (TDR) tracks of chinstrap penguins, Pygoscelid antarcticus, at the South Orkney Islands (Signy, Monroe, Powell and Laurie Island) from 2011 to 2019. Chinstrap penguins were fitted with TDR tags between December to January (austral summer) to better understand their movement for seabird conservation and management. The data includes temperature and pressure at specified intervals for deployed tags, with additional metadata on the morphology of the birds, their deployment, and breeding. Work was carried out by personnel at the British Antarctic Survey (BAS) and was funded by Natural Environment Research Council (UK) core funding to BAS. This is an updated version of a previous dataset. There have been additional tracks included with further quality control carried out.