A series of 6 sets of midwater trawls in Prydz Bay. Each trawl set took place over a 24 hour period to test the extent of diurnal vertical migration in P. antarcticum. Part of the KROCK cruise of Aurora Australis. These data have been incorporated into an 'historical fish database' available for download at the URL given below (Access Database). These data have also been included in the Australian Antarctic Data Centre's Biodiversity database, and have been submitted to GBIF and OBIS (Global Biodiversity Information Facility, and Ocean Biogeographic Information System). The fields in this dataset are: Species Cruise Start Date End Date Sampling Date Vessel Name Fishing Area Latitude Longitude Gear Length Weight Sex Gonad Weight Stomach Weight

This dataset contains long-term underwater acoustic recordings made under Australian Antarctic Science Projects 4101 and 4102, and the International Whaling Commission’s Southern Ocean Research Partnership (IWC-SORP) Southern Ocean Hydrophone Network (SOHN). Calibrated measurements of sound pressure were made at several sites across several years using custom moored acoustic recorders (MARs) designed and manufactured by the Science Technical Support group of the Australian Antarctic Division. These moored acoustic recorders were designed to operate for year-long, deep-water, Antarctic deployments. Each moored acoustic recorder included a factory calibrated HTI 90-U hydrophone and workshop-calibrated frontend electronics (hydrophone preamplifier, bandpass filter, and analog-digital converter), and used solid state digital storage (SDHC) to reduce power consumption and mechanical self-noise (e.g. from hard-drives with motors and rotating disks). Electronics were placed in a glass instrumentation sphere rated to a depth of 6000 m, and the sphere was attached to a short mooring with nylon straps to decouple recorder and hydrophone from sea-bed. The hydrophone was mounted above the glass sphere with elastic connections to the mooring frame to reduce mechanical self-noise from movement of the hydrophone. The target noise floor of each recorder was below that expected for a quiet ocean at sea state zero. The analog-digital converter, based on an AD7683B chip, provides 100 dB of spurious free dynamic range, but a total signal-to-noise and distortion of 86 dB which yields 14 effective bits of dynamic range at a 1 kHz input frequency. The data for each recording site comprise a folder of 16-bit WAV audio files recorded at a nominal sample rate of 12 kHz. The names of each WAV file correspond to a deployment code followed by the start time (in UTC) of the file as determined by the microprocessor’s real-time clock e.g. 201_2013-12-25_13-00-00.wav would correspond to a wav file with deployment code 201 that starts at 1 pm on December 25th 2013 (UTC). Recording locations were chosen to correspond to sites used during AAS Project 2683. These sites were along the resupply routes for Australia’s Antarctic stations, and typically there was only one opportunity to recover and redeploy MARs each year.

Despite being a ubiquitous and abundant component of the Southern Ocean ecosystem, pack-ice seals (crabeater, Ross and leopard seals) are notoriously difficult to census as they are sparsely distributed over large regions of remote pack-ice. Historically, population censuses have been made from ship- or helicopter-based surveys, which are expensive and logistically difficult, and this inevitably leads to data which are limited, in time and space. High resolution images allow us now to accurately census seals e.g. elephant and Weddell seals at unprecedented spatial and temporal scales. Using this technology promises to provide regular estimates of the numbers of pack-ice seals in important regions such as Prydz Bay This study will develop techniques to survey pack-ice seals from high resolution satellite images, including automatic detection functions and a preliminary habitat model based on the characteristics of the ice contained in the images.

This data set was collected from two minicosm experiments conducted at Davis Station, Antarctica. 1. Variance experiment - 2013/14 summer season 2. Ocean acidification experiment - 2014/15 summer season It includes: - description of methods for all data collection and analyses. - environmental data logged throughout the experiment; nutrients, temperature, light climate. - flow cytometry counts; autotrophic cells, heterotrophic nanoflagellates, and prokaryotes. - FlowCam counts; individual phytoplankton species data. - microscopy counts; individual phytoplankton species data.

Digital Elevation Model of the Amery Ice Shelf derived from ERS satellite radar altimetry elevation data. Generated on a 1-km polar stereographic grid using kriging in four sections by Helen Amanda Phillips, Antarctic CRC/IASOS. Three files are available for download: Amery Ice Shelf DEM from satellite altimeter data version relative to WGS-84 ellipsoid, Amery Ice Shelf DEM from satellite altimeter data version relative to EGM96 geoid, A thickness dataset that was derived from the AIS-DEM. Each file constitutes 122,385 lines of data (+ 4 lines of header information). The fields in this dataset are: Latitude Longitude Geodial Height in metres above sea level (WGS-84 and EGM-96) Thickness

Metadata record for data from ASAC Project 2751 See the link below for public details on this project. Public Viruses are tiny particles that cannot reproduce by themselves. To reproduce they have to parasitise a bacterial cell, or another organism. In the sea viruses infect bacteria and phytoplankton cells and can cause those cells to die and break open, thereby liberating more virus particles into the environment to re-infect more host cells. They effectively short-circuit the carbon cycle - recycling carbon to the pool of dissolved and particulate organic carbon before it can be eaten by organisms higher in the food chain. Our research will elucidate the role of viruses in the water column and sea-ice over a year. Taken from the 2008-2009 Progress Report: Project objectives: BACKGROUND Since the microbial loop was first described, a wealth of data has appeared on the species composition and interactions among bacterioplankton and Protozoa, both heterotrophic and mixotrophic, and their role in biogeochemical cycling in marine and lacustrine environments. An additional dimension to the microbial loop was discovered when high concentrations of viruses (bacteriophage) were first described from marine samples. The supposition was that infected bacteria might be lysed, and their carbon returned to the pool before it could be grazed by Protozoa, short-circuiting the microbial loop. Both heterotrophic bacteria and cyanobacteria were found to be infected by viruses and later work revealed that viruses may also attack algae and protists, but the database on the viruses of these groups is far less detailed than for bacteriophages. Viruses are now the focus of considerable attention in aquatic environments. The role of viruses is more complex than simply causing the mortality of bacteria and phytoplankters. Viruses also play a role in maintaining the clonal diversity of host communities through gene transmission (transduction), and indirectly by causing the mortality of dominant host species. Moreover, viruses can act as a potential source of food for heterotrophic and mixotrophic flagellates. Based on decay rates an ingestion of 3.3 viruses per flagellate h-1 was calculated, and experiments with fluorescently labelled microspheres demonstrated that nanoflagellates may gain significant carbon through ingesting viruses. Early studies suggested that the majority of viruses in marine waters were lytic. More recently lysogeny has been found in both marine and freshwater systems ranging up to 71% in both marine and freshwaters. Thus aquatic viruses may exist in a lysogenic condition within their hosts where they replicate and are passed on in the host's progeny during division. This condition may continue until a factor, or a combination of factors, initiates the lytic cycle. Clearly it is disadvantageous to embark on a lytic cycle when the concentration of potential hosts is low. Long term seasonal studies of viruses and their potential hosts are relatively few, and have focussed on a specific aspects, for example the abundance of lysogenic bacteria in an estuary and Lake Superior and viral control of bacterial production in the River Danube. A recent study of annual patterns of viral abundance and seasonal microbial plankton dynamics in two lakes in the French Massif Central, suggested that a weakened correlation between viruses and bacteria in the more productive of the two lakes was indicative of an increase in non-bacterial hosts as trophic status increased. We have conducted a year long study of virus dynamics in three of the saline lakes in the Vestfold Hills, our hypothesis being that they may be regarded as a proxy for the marine environment, but with the difference that top-down control is lacking in food webs that are microbially dominated. Our results revealed that virus numbers showed no clear seasonal pattern and were high in winter and summer (range 0.89 x 107 plus or minus 0.038 mL-1 to 12.017 x 107 plus or minus 1.28 mL-1). However, the lysogenic cycle was predominant in winter (up to 73% of the bacteriophage were lysogenic), while in summer the lytic cycle dominated. There was a strong negative correlation between virus numbers and photosynthetically active radiation. Viruses are subject to destruction or decay when subjected to full sunlight, even when UV- B radiation is excluded. During summer in Antarctica there is 24 hour daylight as well as significant UV-B radiation in spring and early summer when one might expect high levels of viral decay. UV-B radiation penetrates lake ice and the water column, though attenuation is rapid. PAR and UV-B penetration to the water column increases as the ice thins. It is likely that low decay rates in winter allowed the survival and build up of VLP numbers, while in summer when the lytic cycle predominated, decay rates were high. Seasonal variation in decay rates may in part account for the poor correlation between bacterial numbers and VLP in our study. High virus to bacteria ratios in the saline lakes (reaching 115 in Pendant Lake) and viral production rates comparable to those seen in temperate lakes suggest that viruses may play an important role in these microbially dominated extreme environments. Data from Antarctic marine waters are limited. Bacteria to virus ratios ranged between 15 - 40 in the sea-ice region, but were lower (3-15) in the open ocean. Higher ratios under ice may indicate that ice and its impact on light climate, reduces viral decay rates and enhances the ratios between bacteria and viruses. The sea-ice itself provides another habitat for bacteria and their viral parasites with abundances of viruses reaching 109 mL-1. OVERALL AIM We wish to undertake a year long study in the inshore marine environment in Prydz Bay focussing on viral dynamics in relation to microbial loop functioning. We will investigate the water column and the communities within the sea-ice. Within the context of the International Polar Year it is important that we further knowledge of microbial processes in the Southern Ocean. Changes in the length and thickness of ice-cover in response to climate warming and the impact on the sea-ice community, may have knock on impacts on water column microbial community and carbon cycling. SPECIFIC OBJECTIVES: 1. The quantify viral dynamics (numbers, production and levels of lysogeny) within the context of the microbial loop processes in the water column and sea-ice of Prydz Bay over an annual cycle. 2. To link viral/bacterial dynamics to physical and chemical parameters such as temperature, UV radiation, Photosynthetically Active Radiation, dissolved organic carbon (DOC) and total organic carbon (TOC) and inorganic nutrients. (N and P). 3. To ascertain linkages between microbial processes iin the sea-ice and water column, particularly during the melt phase. 4. To ascertain the effects of UV-B on viral decay rates below ice and in the open water phase. Progress against objectives: Detailed time series sampling of the sea ice in Prydz Bay has been completed. Bacterial production and viral production, along with the level of lysogeny were conducted. Abundances of viruses, bacterial and nanoflagellates have been completed. Chlorophyll, DOC and TOC, inorganic nutrients also completed. Ciliate samples are still to analysed as are frozen preparations from viral production and lysogeny experiments.

Metadata record for data from ASAC Project 288 See the link below for public details on this project. From the abstract of the referenced paper: In January-February 1991, in Prydz Bay, phytoplankton bloom was evident in the inner shelf area with the dominant diatoms being represented mainly by pennate species of the Nitzschia-Fragilariopsis group. Dinoflagellates and naked flagellates were most abundant in the centre of the bay; however, larger heterotrophic species prevailed at the southern stations. Cell carbon values (average 317 micro grams per litre; range 92-1048 micrograms per litre) found in the bloom in the south were chiefly due to pennate diatoms and larger heterotrophic dinoflagellates. Much lower carbon values (average 51 micro grams per litre; range 7-147 micro grams per litre) in the outer shelf region were mainliy contributed by large centric diatoms (70-110 micro metres) and small dinoflagellates (5-25 micro metres). Wide ranges of algal cell sizes were observed in both southern and northern communities; the overlapping of sizes of diatoms and flagellates, the latter containing heterotrophs, suggested complex trophic relationships within the plankton and an enhanced heterotrophic activity in the south. North-to-south variations in surface delta 13 C of suspended particulate organic matter (SPOM), (range -31.85 to -20.12 parts per thousand) were directly related to the concentration of particulate matter: this suggested the effect of biomass, and thus of dissolved CO2 limitation on carbon fractionation. Three types of species assemblages were distinguished, corresponding to different narrow ranges of delta 13 C values (-20.12 to -22.37 parts per thousand; -24.50 to -26.65 parts per thousand; -29.73 to -31.85 parts per thousand); dominant species within each assemblage are the likely major determinants of the carbon isotopic composition and variation of SPOM. Pennate diatoms, such as Nitzschia curta and N. subcurvata appear to have made the major imprint on the highest delta 13 C values. Phaeocystis, naked flagellates, autotrophic dinoflagellates and centric diatoms are likely to have caused the lower delta 13 C values of SPOM. It appears that variations in both biomass concentration and in phytoplankton species composition have contributed to the carbon isotopic values of SPOM in Prydz Bay.

From the abstract and introduction of ANARE Research Notes 44 - ADBEX I cruise to the Prydz Bay region, 1982: nutrient data. Nitrate, phosphate and silicate concentrations obtained during the ADBEX I cruise to the Prydz Bay region in November and December 1982 are plotted with depth and the raw data are tabulated. Location of the sampling stations and the average concentration of each nutrient in the top 100 m of the water column is mapped. The ADBEX I (Antarctic Division BIOMASS Experiment) cruise is part of a long-term, national program of field surveys aimed at fulfilling the objectives of the BIOMASS (Biological Investigation of Marine Antarctic Systems and Stocks) program. The ADBEX I cruise on MV Nella Dan to the Prydz Bay region between 19 November and 17 December 1982, is the second Antarctic Division cruise to contribute to BIOMASS, the first being FIBEX (First International Biomass Experiment) in 1981. Nutrient data were collected at twenty-eight of the seventy-nine hydrographic stations to provide information for the interpretation of phytoplankton distribution and abundance. The sampling locations and depths were not selected, therefore, on the basis of nutrient-related considerations. The concentration of nitrate, phosphate and silicate is plotted to 600 m for each station and where casts were much deeper or much shallower, a second plot is shown. To show water column structure at the time of sampling, sigma-t values were also plotted, unless data for a cast were unavailable. In addition to the depth profiles, the average concentration to 100 m of each nutrient species is mapped to give a first-order approximation of the horizontal pattern of nutrient distribution in the upper layers.

The body surface, mouth, gills, internal organs and tissues of 368 teleost fish of 26 species from Prydz Bay, Heard Island, Macquarie Island, Davis Station and Casey Station in Antarctica were examined for parasites. At least eight species of Monogenea, seven species of Copepoda, and five or six species of Acanthocephala were recorded. Overall, the fauna of Monogenea and Copepoda of Antarctic fish is much poorer than that of lower latitudes, and there are fewer species of Gyrodactylidae relative to other Monogenea than at higher northern latitudes. Abundance and species richness of Acanthocephala are relatively high.