Sampling strategy: Samples from trawls or sledges are sieved on the trawl deck then sorted in the wet lab per taxonomic group. Sorting may vary from high taxonomic levels (order, family) to specific ones according to expertise on board. For some taxa, sampling includes: up to 10 voucher specimens with a unique batch number; photos; tissue samples in 80% ethanol for DNA analysis (Barcoding and Phylogeny); 30 samples minimum for population genetics (for abundant species); sampling for isotopic measures; fish chromosomes preparations; primary fish cell lines and cryopreservation of fish tissues for permanent cell lines The database was intended to contain information about stations, events, gear, all material collected and associated samples listed above. currently only contains information on material collected and samples. Data was recorded on log sheets then transcribed into an Oracle database called cabo. Tailor made user interace for entering data. No export functionality. SQL database dump has been provided but there was no-one on the voyage to elaborate on the structure, this was promised post voyage along with some simple data exports to match the log sheets, so we have access to the data without the unfriendly database.

A meta-analysis was undertaken to examine the vulnerability of Antarctic marine biota occupying waters south of 60 degrees S to ocean acidification. Comprehensive database searches were conducted to compile all English language, peer-reviewed journals articles and literature reviews that investigated the effect of altered seawater carbonate chemistry on Southern Ocean and/or Antarctic marine organisms. A document detailing the methods used to collect these data is included in the download file.

Metadata record for data from ASAC Project 756 See the link below for public details on this project. From the abstract of one of the referenced papers: The shore environments of most sub-Antarctic islands have been described in a number of previous studies. However there have been few attempts to quantify the population and community patterns over different spatial scales. The objectives of this study were to provide an analysis of the differences in the community structure of the biota of three exposed shore zones and of the macrofauna inhabiting holdfasts of the kelp Durvillaea antarctica across spatial scales of hundreds of metres, kilometers, and between a sheltered and exposed coast. Data were collected using a combination of quadrat, transect and direct sampling methods over the 1994-95 summer season. The results indicated that there were significant differences between coast for some of the biotic variables in most of the habitats examined but that differences at the smaller spatial scales were more often significant. Thus, although wave exposure exerts an obvious effect on the shore biota of Macquarie Island, these effects are modified by other factors operating at smaller spatial scales. For the holdfast macrofauna, the overall patterns of community structure are likely to be due to the differential response of the component taxa to variation in holdfast volume and holdfast sediment content as well as other, currently undetermined factors.

Metadata record for data from AAS (ASAC) Project 2933. See the child records for access to the datasets. Public While it is generally thought that Antarctic organisms are highly sensitive to pollution, there is little data to support or disprove this. Such data is essential if realistic environmental guidelines, which take into account unique physical, biological and chemical characteristics of the Antarctic environment, are to be developed. Factors that modify bioavailability, and the effects of common contaminants on a range of Antarctic organisms from micro-algae to macro-invertebrates will be examined. Risk assessment techniques developed will provide the scientific basis for prioritising contaminated site remediation activities in marine environments, and will contribute to the development of guidelines specific to Antarctica. Project objectives: 1. Develop and use toxicity tests to characterise the responses of a range of Antarctic marine invertebrates, micro- and macro-algae to common inorganic and organic contaminants. 2. To examine factors controlling bioavailability and the influence of physical, chemical and biological properties unique to the Antarctic environment on the bioavailability and toxicity of contaminants to biota. 3. To compare the response of Antarctic biota to analogous species in Arctic, temperate and tropical environments in order to determine the applicability of using toxicity data and environmental guidelines developed in other regions of the world for use in the Antarctic. 4. Develop a suite of standard bioassay techniques using Antarctic species to assess the toxicity of mixtures of contaminants (aqueous and sediment-bound) including tip leachates, sewage effluents and contaminated sediments. 5. To establish risk assessment models to predict the potential hazards associated with contaminated sites in Antarctica to marine biota, and to develop Water and Sediment Quality Guidelines for Antarctica to set as targets for the remediation of contaminated marine environments. Taken from the 2008-2009 Progress Report: Progress against objectives: Due to logistical constraints, only a short field season (5 weeks) was conducted at Casey in 2008/09 and no berths were allocated solely to this project. A team of 6 scientists worked together on an intensive marine sampling program under TRENZ (AAS project 2948, CI Stark) in support of 5 different AAS projects, including this one. The lack of adequate personnel dedicated to this project and the limited time that we were allocated on station hindered progress and meant that no experiments on Antarctic organisms were able to be conducted in situ. The airlink was however successfully used to transport marine invertebrates collected at Casey and held in seawater at 0degC back to Hobart on 3 separate flights. These invertebrates are currently being maintained in the cold water ecotoxicology aquarium facilities at Kingston. Once they are sorted and where possible established in cultures, they will be used in toxicity tests. Progress against specific objects are: 1) Much effort and time has been put towards the husbandry and culture of the collected Antarctic marine invertebrates. Some species are now successfully breeding in the laboratory providing new generations and sensitive juvenile stages of invertebrates to work with in toxicity tests. This culturing capability, if able to be developed, will hugely extend opportunities for carrying out research for this project, by giving us access to live material over the winter months and during summer when berths to or space on station in Antarctica is limited. Toxicity tests using some of the common amphipods and gastropods collected in the 0809 season at Casey will commence shortly at Kingston. 2) Toxicity tests to commence shortly using invertebrates collected in the 0809 season now being maintained in the Ecotoxicology aquarium will focus on interactions and potentially synergistic effects of contaminants along with other environmental stressors including increases in temperature and decreases in salinity associated with predicted environmental changes in response to climate change. 3) A phD candidate has recently started on this project and is currently reviewing all available literature on the response of Antarctic species to contaminants and environmental stressors in comparison to related species from lower latitudes. 4) Invertebrates collected in the 0809 season that are being maintained in the Ecotoxicology aquarium will be screened in toxicity tests to commence shortly. Methods will then be developed using the most suitable and sensitive species to form the basis of standard bioassay procedures that can be used to test mixtures such as sewage effluents and tip leachates in the upcoming season. 5) The establishment of risk assessment models and Environmental Quality Guidelines for Antarctica is a long term goal of this project when data from the first 4 objectives can be synthesised and hence has not yet been addressed. Taken from the 2009-2010 Progress Report: Progress against objectives: Objectives 1 and 2: Metal effects on the behaviour and survival of three marine invertebrate species were investigated during the field season. Two replicate toxicity tests were conducted on the larvae of sea urchin Sterechinus neumayeri where combined effects of metal (copper and cadmium) and temperature (-1, 1 and 3 degrees Celsius) were to be investigated on developmental success. However, due to lower than optimal fertilisation success, both tests were terminated before any meaningful results could be derived. Four tests were conducted on the adult amphipod, Paramorea walkeri. Two replicate tests investigated combined metal (copper and cadmium) and temperature (-1, 1 and 3 degrees Celsius) effects, and two tests investigated the effects of copper, cadmium, lead, zinc and nickel exposure at ambient sea water temperature of -1 degrees Celsius. One test was conducted with the micro-gastropod Skenella paludionoides being exposed to copper, cadmium, lead, zinc and nickel at ambient sea water temperature. The larvae of bivalve Laternula sp. were also investigated as a potential test organism for metal toxicity. Strip spawning was conducted a number of times, however, this technique did not provide adequate levels of fertilisation success and as such, the toxicity tests on larval development were not completed. Objective 3: A phD candidate working on this project is in the process of compiling a review of all available date on the response of Antarctic species to contaminants and environmental stressors in comparison to related species from lower latitudes. This literature review will form a major component of her thesis' first chapter Objective 4: Methods for Standard bioassay procedures were developed using the most suitable and sensitive species, the amphipod Paramoera walkeri and the microgastropod Skenella paludionoides. These standard tests were then used to assess the toxicity of sewage effluent at Davis Station (in conjunction with project 3217). Objective 5: Toxicity tests on sewage effluent were conducted as part of a risk assessment to determine hazards associated with the current discharge. The determined toxicity of the sewage effluent will provide a basis for guideline recommendations on the required level of treatment and on what constitutes an adequate or 'safe' dilution factor for dispersal of the effluent discharge to the near shore marine environment.

Metadata record for data expected from ASAC Project 250 See the link below for public details on this project. The study investigated the impacts of oiling on the biota of rocky shores. Five shore zones were evaluated and kelp holdfasts were collected (but not evaluated as part of this project). Data were collected using quadrat and line transect methods using counts and percentage cover as variables. Data for this work was also used in ASAC projects 672 and 1003 (ASAC_672, ASAC_1003). This dataset contains the 1988 data only. The site codes used in this project are: SB = Sandy Bay SEC = Secluded Bay BB = Buckles Bay GC = Garden Cove GG = Green Gorge GB = Goat Bay The first number given after the site code is the site number at that sampling location. The second number is the replicate at that site. Thus sb(1)3 is Sandy Bay site 1, replicate 3. The numbers are total individuals of each species that were found in each holdfast sample. This is a basic, though standard, species-abundance matrix. The fields in this dataset are: Species Year Site

Metadata record for data from AAS (ASAC) Project 2933. See the child records for access to the datasets. Public While it is generally thought that Antarctic organisms are highly sensitive to pollution, there is little data to support or disprove this. Such data is essential if realistic environmental guidelines, which take into account unique physical, biological and chemical characteristics of the Antarctic environment, are to be developed. Factors that modify bioavailability, and the effects of common contaminants on a range of Antarctic organisms from micro-algae to macro-invertebrates will be examined. Risk assessment techniques developed will provide the scientific basis for prioritising contaminated site remediation activities in marine environments, and will contribute to the development of guidelines specific to Antarctica. Project objectives: 1. Develop and use toxicity tests to characterise the responses of a range of Antarctic marine invertebrates, micro- and macro-algae to common inorganic and organic contaminants. 2. To examine factors controlling bioavailability and the influence of physical, chemical and biological properties unique to the Antarctic environment on the bioavailability and toxicity of contaminants to biota. 3. To compare the response of Antarctic biota to analogous species in Arctic, temperate and tropical environments in order to determine the applicability of using toxicity data and environmental guidelines developed in other regions of the world for use in the Antarctic. 4. Develop a suite of standard bioassay techniques using Antarctic species to assess the toxicity of mixtures of contaminants (aqueous and sediment-bound) including tip leachates, sewage effluents and contaminated sediments. 5. To establish risk assessment models to predict the potential hazards associated with contaminated sites in Antarctica to marine biota, and to develop Water and Sediment Quality Guidelines for Antarctica to set as targets for the remediation of contaminated marine environments. Taken from the 2008-2009 Progress Report: Progress against objectives: Due to logistical constraints, only a short field season (5 weeks) was conducted at Casey in 2008/09 and no berths were allocated solely to this project. A team of 6 scientists worked together on an intensive marine sampling program under TRENZ (AAS project 2948, CI Stark) in support of 5 different AAS projects, including this one. The lack of adequate personnel dedicated to this project and the limited time that we were allocated on station hindered progress and meant that no experiments on Antarctic organisms were able to be conducted in situ. The airlink was however successfully used to transport marine invertebrates collected at Casey and held in seawater at 0degC back to Hobart on 3 separate flights. These invertebrates are currently being maintained in the cold water ecotoxicology aquarium facilities at Kingston. Once they are sorted and where possible established in cultures, they will be used in toxicity tests. Progress against specific objects are: 1) Much effort and time has been put towards the husbandry and culture of the collected Antarctic marine invertebrates. Some species are now successfully breeding in the laboratory providing new generations and sensitive juvenile stages of invertebrates to work with in toxicity tests. This culturing capability, if able to be developed, will hugely extend opportunities for carrying out research for this project, by giving us access to live material over the winter months and during summer when berths to or space on station in Antarctica is limited. Toxicity tests using some of the common amphipods and gastropods collected in the 0809 season at Casey will commence shortly at Kingston. 2) Toxicity tests to commence shortly using invertebrates collected in the 0809 season now being maintained in the Ecotoxicology aquarium will focus on interactions and potentially synergistic effects of contaminants along with other environmental stressors including increases in temperature and decreases in salinity associated with predicted environmental changes in response to climate change. 3) A phD candidate has recently started on this project and is currently reviewing all available literature on the response of Antarctic species to contaminants and environmental stressors in comparison to related species from lower latitudes. 4) Invertebrates collected in the 0809 season that are being maintained in the Ecotoxicology aquarium will be screened in toxicity tests to commence shortly. Methods will then be developed using the most suitable and sensitive species to form the basis of standard bioassay procedures that can be used to test mixtures such as sewage effluents and tip leachates in the upcoming season. 5) The establishment of risk assessment models and Environmental Quality Guidelines for Antarctica is a long term goal of this project when data from the first 4 objectives can be synthesised and hence has not yet been addressed. Taken from the 2009-2010 Progress Report: Progress against objectives: Objectives 1 and 2: Metal effects on the behaviour and survival of three marine invertebrate species were investigated during the field season. Two replicate toxicity tests were conducted on the larvae of sea urchin Sterechinus neumayeri where combined effects of metal (copper and cadmium) and temperature (-1, 1 and 3 degrees Celsius) were to be investigated on developmental success. However, due to lower than optimal fertilisation success, both tests were terminated before any meaningful results could be derived. Four tests were conducted on the adult amphipod, Paramorea walkeri. Two replicate tests investigated combined metal (copper and cadmium) and temperature (-1, 1 and 3 degrees Celsius) effects, and two tests investigated the effects of copper, cadmium, lead, zinc and nickel exposure at ambient sea water temperature of -1 degrees Celsius. One test was conducted with the micro-gastropod Skenella paludionoides being exposed to copper, cadmium, lead, zinc and nickel at ambient sea water temperature. The larvae of bivalve Laternula sp. were also investigated as a potential test organism for metal toxicity. Strip spawning was conducted a number of times, however, this technique did not provide adequate levels of fertilisation success and as such, the toxicity tests on larval development were not completed. Objective 3: A phD candidate working on this project is in the process of compiling a review of all available date on the response of Antarctic species to contaminants and environmental stressors in comparison to related species from lower latitudes. This literature review will form a major component of her thesis' first chapter Objective 4: Methods for Standard bioassay procedures were developed using the most suitable and sensitive species, the amphipod Paramoera walkeri and the microgastropod Skenella paludionoides. These standard tests were then used to assess the toxicity of sewage effluent at Davis Station (in conjunction with project 3217). Objective 5: Toxicity tests on sewage effluent were conducted as part of a risk assessment to determine hazards associated with the current discharge. The determined toxicity of the sewage effluent will provide a basis for guideline recommendations on the required level of treatment and on what constitutes an adequate or 'safe' dilution factor for dispersal of the effluent discharge to the near shore marine environment.

Metadata record for data expected from ASAC Project 996 See the link below for public details on this project. The study investigated the effects of the small sewage outfall on algal epifauna in the isthmus area. No impacts were detected and patterns of community structure were tentatively explained by local differences in wave exposure gradients. From the abstract to the referenced paper: As part of a wider programme investigating the effects of human presence on Antarctic and sub-Antarctic ecosystems, this study evaluated the impact of the small sewage outfall at Macquarie Island on the epifauna living within turfs of the intertidal red alga Chaetangium fastigiatum. Sampling was conducted during early December (austral summer) in both 1996 and 1997 at six sites, two sites within each of three adjacent bays. The site closest to the outfall was 3m from the point of discharge. Data analyses at the population and community levels failed to demonstrate a significant effect of the outfall. Small scale spatial patterns, probably related to wave exposure, and inter-annual variation in recruitment, are suggested as the main causes of variation in patterns of epifaunal dominance during the study. The site codes used in this dataset are: GCS - Garden Cove South GCN - Garden Cove North GBS - Bay 1 South GBN - Bay 1 North CS - Bay 2 North CN - Bay 2 South At each site 5 replicates were taken. The numbers are total individuals of each species that were found in each Chaetangium sample. This is a basic, though standard, species-abundance matrix. The fields in this dataset are: Species Site Year

Metadata record for data from ASAC Project 102 See the link below for public details on this project. From the abstracts of some of the referenced papers: Six species of marine microalgae, namely Phaeodactylum tricornutum Bohlin, Dunaliella tertiolecta Butcher, Isochrysis galbana Parke, Porphyridium purpureum (Bory) Ross, Chroomonas sp., and Oscillatoria woronichinii Anis., have been examined with respect to their gas exchange characteristics and the inorganic carbon species taken up by the cells from the bulk medium. All species showed a high affinity, in photosynthesis, for inorganic carbon and low CO2 compensation concentrations. Such data are suggestive of operation of a 'CO2-concentrating mechanism' in these microalgae. Direct measurements of internal organic carbon pools in four of the species studied confirm this (O. woronichinii and Chroomonas were not tested). By comparison of achieved photosynthetic rates with calculated rates of CO2 supply from the dehydration of bicarbonate, it was shown that Phaeodactylum, Porphyridium and Dunaliella could utilise the bicarbonate present in the medium. Data for the other species were inconclusive although the pH dependence of K 1/2CO2 for photosynthesis by Oscillatoria indicated that this species too could utilise bicarbonate. Such observations could, however, not be used as evidence that, at least in the eucaryotic algae examined, bicarbonate was the inorganic carbon species crossing the plasmalemma as Phaeodactylum, Porphyridium and Dunaliella, and Isochrysis all showed the presence of carbonic anhydrase activity in intact cells as well as in crude extracts. 'External' carbonic anhydrase activity represented from 1/4 to 1/2 of the total activity in the cells of these algae. It is concluded that, as a consequence of a CO2-concentrating mechanism, photorespiration was suppressed in the marine microalgae examined although the data obtained did not allow any firm conclusions to be drawn regarding the species of inorganic carbon transported into the cell. Analysis of the age composition of a given species within a community is fundamental to any study of population dynamics and to the subsequent analyses of community interactions such as competition, succession and productivity. A problem exists in that calendar age often provides little information on the role played by any given individual plant within a population. For many populations the most useful definition of population structure is obtained from an analysis of both the functional age and the vitality of the component plants. Data from such studies on populations of marine macroalgae are lacking mainly because of the lack of suitable methods. This paper provides a review of the methods which have ben applied to such analyses in both terrestrial and marine communities, discusses these methods in the context of marine algae and presents the results of a case study on the analysis of population structure in the large brown alga Durvillaea potatorum. Evidence is presented for the occurrence of sexual reproduction including plasmogamy and meiosis, events previously undescribed in the life history of Ascoseira mirabilis. Ascoseira is monoecious. Gametangia are formed in chains within conceptacles. Synaptonemal complexes, structures concerned with chromosome pairing in meiosis, have been observed in the nucleus of gametangial initials. Mature male and female gametes have the same size and appearance, and resemble typical brown algal zoids. Sexual interaction begins after the female gamete settles down, and both zygotes and unfused gametes develop into sporophytes. It is concluded that Ascoseira has the same basic pattern of life history that characterises the order Fucales, and it is argued that this is probably the result of convergent evolution rather than being indicative of close phylogenetic relationship. Life histories are of central importance in understanding evolution and phylogeny of brown algae. Like other hereditary traits, life history characteristics evolve by processes of natural selection, but because they are important determinants of biological fitness they have special evolutionary significance. Concepts of life history, as traditionally applied to brown algae, do not adequately reflect this, and they need to be broadened to include consideration of additional characteristics such as longevity and reproductive span. Life histories can be interpreted as adaptive strategies. Experimental evidence indicates that heteromorphic life histories probably evolved in response to seasonal change. Isomorphic life histories are possible adapted to stale environments, although some may also possess certain features which are adaptations to seasonal change. Life histories that lack an independent gametophyte generation may have evolved through reduction of heteromorphic life histories. It is argued that a significant increase in the longevity of sporophytes may have ben critical for the evolution of life histories lacking a free-living gametophyte, and also for the evolution of oogamy, phenomena which have occurred in several brown algal evolutionary lines. The common absence of asexual reproduction in advanced taxa probably indicates that its accessory ecological role in maintaining population size has become redundant, as well as reflecting the advantage of sexual over asexual reproduction. However, there is good evidence that sexual reproduction has been lost in a few species of brown algae, and the possible mechanisms and adaptive significance of this are discussed. Studies on Durvillaea antarctica on Macquarie Island, in the subantarctic, were conducted throughout the 1984 and in the summers of 1983 and 1985. Thereafter the annual sequence of conceptacle initiation, development, maturation and senescence was examined, using light and electron microscopy. Durvillaea antarctica on Macquarie Island releases mature ova and spermatozooids from February to Ausgust, with early stages of conceptacle development being observed during November, December and January, and senescent conceptacles from September to December. Both intertidal and subtidal forms of Durvillaea antarctica are found on Macquarie Island, the subtidal form lacking air cavities. In the light of mating experiments which resulted in successful cross-fertilisation, the two forms are considered to be conspecific.

Metadata record for data from ASAC Project 2914 See the link below for public details on this project. Can animals raft between countries on floating seaweed? We aim to answer that question using powerful genetic tools. We can tell whether gene flow is strong between populations of animals by comparing their mitochondrial DNA; this could show us whether animals from one species in New Zealand are isolated from individuals of the same species in Chile. If they are not isolated, how are they managing to maintain gene flow? We know there are many millions of clumps of floating seaweed in the Southern Ocean, and these might provide a means of intercontinental travel for a range of small invertebrates. Project objectives: The primary objective of the project is to determine the effectiveness of rafting as a dispersal mechanism for sessile and semi-sessile organisms around the Southern Ocean using genetic tools. The secondary objectives, by which the primary objective will be addressed, are: - to examine the biogeography of bull kelp (Durvillaea antarctica) and its holdfast fauna around the Southern Ocean - to undertake genetic analysis of a wide range of macroalgal (seaweed) species throughout the Southern Ocean to assess 1) whether sea ice indeed extended further north than previously believed, and 2) the ecological and evolutionary impacts of historic ice scour on Southern Ocean islands. - to determine which holdfast invertebrates are the most common and ubiquitous in holdfasts of Durvillaea antarctica around the Southern Ocean - to compare the genetic structure of populations of both the kelp itself, and select invertebrate taxa* from its holdfasts, on a number of spatial scales: --- genetic variation at HOLDFAST level: are members of a single species, e.g., the isopod Limnoria stephenseni, closely related within a single holdfast? --- genetic variation at SITE level: are members of a single species, e.g., Durvillaea antarctica itself, closely related at one site? In this case, a 'site' means a single intertidal rock platform. --- genetic variation at NATIONAL level: are there distinct biogeographic separations of species, or does a single species show distinct genetic disjunction, along the Chilean coastline and around the south island of New Zealand? --- genetic variation at OCEAN level: are species clearly connected (by gene flow) between Southern Ocean landmasses? The landmasses of interest are: Chile, New Zealand, and the subantarctic islands on which Durvillaea antarctica grows. * The proposed taxa that this project will focus on are: the isopod genus Limnoria; the amphipod Parawaldeckia kidderi; the chiton genus Onithochiton; the polychaete worm families Terebellidae and Syllidae; a topshell; a bivalve; barnacles. Progress against objectives: Considerable progress has been made against the primary objective since the start of the project in 2006. We have collected (/ been sent) and analysed samples of bull-kelp (Durvillaea antarctica) and its associated invertebrate holdfast fauna from numerous sites around the Southern Ocean (subantarctic islands including Macquarie, Gough, Marion, Kerguelen, Crozet, Auckland, Antipodes, Campbell, Falkland Islands; along the coasts of New Zealand and Chile). Our results thus far have allowed us to determine not only that rafting facilitates long-distance dispersal of these otherwise sedentary taxa, but also that sea ice during the last ice ice likely had significant impacts on subantarctic intertidal ecosystems. Our conclusions have been published in several papers in high-impact journals. The secondary objectives, by which the primary objective will be addressed, are: - to examine the biogeography of bull kelp (Durvillaea antarctica) and its holdfast fauna - these objectives have now largely been achieved, and results published. - to undertake genetic analysis of a wide range of macroalgal (seaweed) species throughout the Southern Ocean - this part of the project is ongoing, and will make use of samples collected over the austral summer from Macquarie Island (and other locations around the southern hemisphere). all samples have now been collected and are being processed in the laboratory. - to determine which holdfast invertebrates are the most common and ubiquitous - this objective has been partially achieved (see Nikula et al. 2010), but research is ongoing. - to compare the genetic structure of populations of both the kelp itself, and select invertebrate taxa from its holdfasts, on a number of spatial scales - this objective has been partially achieved (see Nikula et al. 2010 for results of Limnoria and Parawaldeckia genetic research) but additional research on these and other taxa continues. The download file contains an excel spreadsheet detailing collection locations and accession numbers for the samples collected on Macquarie Island. A text document providing accession numbers for non-Antarctic related samples used in this project is also part of the download file.

Human impacts threaten not only species, but also entire ecosystems. Ecosystems under stress can collapse or transition into different states, potentially reducing biodiversity at a variety of scales. Here we examine the vulnerability of shallow invertebrate-dominated ecosystems on polar seabeds, which may be threatened for several reasons. These unique communities consist of dark-adapted animals that rely on almost year-round sea-ice cover to create low-light shallow marine environments. Climate change is likely to cause early sea-ice break-out in some parts of Antarctica, which will dramatically increase the amount of light reaching the seabed. This will potentially result in ecological regime shifts, where invertebrate-dominated communities are replaced by macroalgal beds. Habitat for these endemic invertebrate ecosystems is globally rare, and the fragmented nature of their distribution along Antarctic coast increases their sensitivity to change. At the same time, human activities in Antarctica are concentrated in areas where these habitats occur, compounding potential impacts. While there are clear mechanisms for these threats, lack of knowledge about the current spatial distribution of these ecosystems makes it difficult to predict the extent of ecosystem loss, and the potential for recovery. In this paper we describe shallow ice-covered ecosystems, their association with the environment, and the reasons for their vulnerability. We estimate their spatial distribution around Antarctica using sea-ice and bathymetric data, and apply the IUCN Red List of Ecosystems criteria to formally assess their vulnerability. We conclude that shallow ice-covered ecosystems should be considered near threatened to vulnerable in places, although the magnitude of risk is spatially variable. This dataset comprises two files. Both are provided in netCDF format in polar stereographic project (see nc file for projection details). light_budget_6km.nc : this gives the estimated annual light budget (in mol photons/m^2/year) at the surface of the water column, having been adjusted for sea ice cover (see paper for details). This is calculated on the 6.25km grid associated with the sea ice concentration data. benthic_light_500m.nc : this gives the estimated annual light budget (in mol photons/m^2/year) at the sea floor, having been further adjusted for water depth. It is provided on a 500m grid (as per the IBCSO bathymetry used). Areas deeper than 200m are given no-data values, and areas outside of the coverage of the sea ice grid are assigned a value of -999. See paper for details.