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SOUTHERN OCEAN

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  • Metadata record for data from ASAC Project 2301 See the link below for public details on this project. ---- Public Summary from Project ---- This study develops and combines the latest molecular and electronics technology into a comprehensive investigation of diet and food-web relationships of Southern Ocean predators (whales, seals, penguins) and commercial marine resources (krill, fish, squid). This type of information is essential for ecosystem models that set sustainable catch limits for fisheries. From the abstract of the referenced paper: We describe seven group-specific primer pairs that amplify small sections of ribosomal RNA genes suitable for identification of animal groups of major importance as prey items in marine ecosystems. These primer sets allow the isolation of DNA from the target animal groups from mixed pools of DNA, where DNA-based identification using universal primers is unlikely to succeed. The primers are designed for identifying prey and animal diets, but could be used in any situation where these animal groups are to be identified by their DNA. Progress report from the 2006/2007 Season: Overall objective This new multi-year initiative project within the AMLR program aims to develop and combine the latest molecular and electronics technology to facilitate a comprehensive investigation of appropriately scaled and strategically located trophodynamics of Southern Ocean higher marine predators and commercial marine living resources. The objectives and early experimental design are largely responsive to needs determined by the Australian Antarctic Division's core-function obligations to CCAMLR, as well as other international organisations, the most relevant of which are the International Whaling Commission (IWC) and Southern Ocean Global Ocean Ecology Dynamics (SO-GLOBEC). Traditionally studies of diet of higher predators have often relied upon the use of a single, uncalibrated, methodology, and samples are usually collected in a manner that precludes stratification by age and sex class. Such studies are often subordinate experiments to a larger overall project. In contrast, the power of this new initiative project will be its focus on calibration across a suite of established and novel molecular and macroscopic techniques, feeding trials in controlled situations, direct linkage of samples to age and sex classes, and a detailed knowledge of the foraging behaviour of a sub-set of sampled animals. The parallel development and incorporation of electronic tools to measure predator foraging ecology further strengthens this work. In order to achieve the aims of this study a multi-disciplinary, widely collaborative and multi-streamed program has been developed. Methodological development underpins the potential power of this project to delivery its objectives. The detailed design-phase of incorporating these new approaches into an experimental framework will follow this developmental phase. In order to best represent the sub-objectives of each phase of this study, the work has been divided into the following core components: * Experimental Design (phase 1: methodological development) * Development of DNA-based molecular techniques to measure prey harvesting * Validation trials of molecular techniques * Modelling/analysis to develop a matrix of methodologies to best predict prey composition in predator diet * Development of electronic equipment to measure prey harvesting * Validation trials of electronic equipment * Experimental Design (phase 2: ecological experiments) * Integrated, question driven, field experiments Some components of this work will run contemporaneously (eg. development of molecular and electronic tools). This project has now been completed. The novel DNA based methods for studying animal diet have been researched thoroughly in controlled conditions and demonstrated to be useful and an advance on existing methods. The DNA based dietary methods have also been successfully applied to studying the diet of Blue whales, Fin whales, Antarctic fur seals, Macaroni penguins, Antarctic krill and bottlenose dolphins.

  • Current meter S4_212b is one of four current meters deployed off the coast of Casey Station, Australian Antarctic Territory. S4_211a was located in Shannon Bay at 66 degrees 16.727 minutes South, 110 degrees 31.434 minutes West. Further deployment details can be found in the 'Mooring Details' section of the data, as well as a 'Location Map'. The data includes: current speed components, current speed and current direction, a progressive vector diagram of displacement, and water temperature. The data were recorded by the Australian Antarctic Division, and processed by Oceanographic Field Services Pty Ltd. Data was recorded between 3:30am 18 November 1997 (GMT) and 7:30am 29 December 1998 (GMT). The fields in this dataset include: Date Time Speed (centimetres per second) Direction (degrees) Temperature (degrees)

  • Metadata record for data from ASAC Project 1117 See the link below for public details on this project. ---- Public Summary from Project ---- The aim of this project is to determine how feasible it is to regularly sample the pelagic under-ice community during winter at a coastal site near Mawson. Very few attempts have been made to sample the water column under the ice during the winter months and the processes that occur during this period remain critical gaps in our knowledge of the Antarctic marine ecosystem. ------------------------------------- The pelagic community under the Mawson sea ice was sampled during the winter of 2001 using 'light trap' sampling devices. The 'light traps' were tested at various depths in a range of configurations to determine whether they were an appropriate instrument to sample the winter pelagic community under the ice. Fourteen successful deployments of the light traps were made on seven separate occasions from 12 June to 12 September 2001. The light traps were deployed at three different depths - the underside of the sea ice, mid water, and just above the sea floor. Two different light sources were used to attract the animals, namely fluorescent tubes and cyalume sticks. Two different configurations of the traps were tested to retain the animals inside the trap - one with plastic flaps to trap the animals, the other with no flaps, allowing the animals to move freely inside the trap. The light traps were deployed and retrieved during darkness to avoid any influence of ambient light. The objectives of the project were met and it is assessed that the pelagic community in winter can be effectively sampled using this methodology. A result of particular interest is the success of the traps in capturing Pleuragramma antarctica, a species which has proven difficult to capture using traditional sampling methods such as nets.

  • A polygonised bathymetric dataset covering the Southern Ocean. The dataset was compiled from data sourced from the General Bathymetric Chart of the Oceans (GEBCO) Digital Atlas, 2003 edition, and the Antarctic Digital Database, version 4.

  • This bibliography contains references to diseases, health, clinical biochemistry and pathology of captive and wild sea birds. The definition of a sea bird is broad and includes all species that feed within the marine environment and others which are related but inhabit other aquatic environments e.g. cormorants. The bibliography is comprehensive but not exhaustive. The compilers would appreciate lists of missed and new items for inclusion. These should be sent to the data officer at the Australian Antarctic Data Centre at the contact details listed below.

  • Metadata record for data from ASAC Project 2307 See the link below for public details on this project. ---- Public Summary from Project ---- The project investigates microbial life in the Southern Ocean. The studies will investigate two areas - the role of bacteria in the regeneration of the important nutrient silica via decomposition of planktonic biomass and to assess the importance of prokaryotic polyunsaturated fatty acid (PUFA) entering the marine food web from natural communities in Antarctic sea ice and the Southern Ocean. Project objectives: 1. Investigate the role of bacteria in the colonisation and decomposition of phytoplankton and concomitant redispersal of silica from phytoplankton in seawater of the Southern Ocean at various different latitudes. 2. Validate real-time PCR (5-prime nuclease PCR assay) for rapid quantification of key bacterial found in seawater to determine their association with phytoplankton decomposition and silica redispersal. Significance: Recent studies (Bidle and Azam, 1999) demonstrate that much silica regeneration in seawater is due to bacterial enzymatic activity and that diatom decomposition and silica release is highly accelerated in the presence of an active colonising bacterial population. The formation of bacterial biofilms and production of extracellular enzymes on phytoplanktic detritus and aggregates appears to lead to the direct breakdown of proteins and polysaccharides which hold together the diatom frustules. In the Southern Ocean this process could be significant as the foodweb there is sustained by phytoplanktonic (mostly diatom) primary productivity (Bunt 1963) whether it be in sea-ice or in the pelagic zone. If silica redispersal does not occur diatoms would instead eventually become buried in sediment with silica supplies becoming limited, except that supplied by aeolian and terrigenous input. In the marine environment half of primary-produced organic matter is degraded by bacteria (Cole et al., 1988). Thus the bacterial decomposition of diatom biomass and subsequent release of dissolved silica should be an important and relatively rapid process in Southern Ocean waters. At this stage there is still limited data on the role of bacteria in regeneration of silica in the overall marine environment. The study of Bidle and Azam (1999) examined seawater off of California and mostly examined the process itself. Currently, the role of specific bacteria is being examined by Kay Bidle (personal communication) and John Bowman is supplying various marine bacteria to assess this. In the proposed study we wish to examine the role of bacteria in the Southern Ocean in the decomposition of diatom biomass, rate of release of dissolved silica and bacterial groups involved in the process. This research should reveal some fundamental knowledge on a integral role of bacteria in Southern Ocean ecosystems. In order to assess the bacterial role in silica redispersal we wish to use three molecular ecological techniques: fluorescent in situ hybridisation (FISH), denaturing gradient gel electrophoresis (DGGE) and real-time PCR. FISH and DGGE analysis are well established in John Bowmans laboratory and are being used routinely for analysis of Antarctic and Tasmanian natural samples (seawater and sediment). The real-time PCR analysis which can be used as a sensitive quantitative assay for bacterial populations in natural samples is currently in development using a recently purchased Rotorgene (Corbett Research) instrument. The method has been used to great effect in measuring rapidly bacterial populations in seawater (eg., Suzuki et al. 2000). Using these methods will allow us to accurately measure changes in bacterial populations during colonisation and decomposition of the diatom biomass during the silica redispersal experiments. There are two data files associated with this project. Part 1: Total of 9 files: File 1. Seawater sample data - information from two cruises in 2000 and 2001 - includes position of sample, types of sample, temperature and analyses performed subsequently. File 2. 16S rRNA gene sequences derived from Southern ocean seawater bacterial isolates. Sequences are all deposited in the GenBank nucleotide database and are in FASTA format. File 3. 16S rRNA gene sequences derived from denaturing gradient gel electrophoretic gel slices via extraction, PCR and cloning. Sequences are all deposited in the GenBank nucleotide database and are in FASTA format. File 4. Flavobacteria abundance in Southern Ocean samples on the basis of depth. Abundance determined using fluorescent insitu hybridisation using universal bacterial probe EUB338 and flavobacteria specific probe. Details of sites analysed are included in the seawater sample file. File 5. Flavobacteria abundance in Southern Ocean samples on the basis of latitude (transect from 47 S to 63 S). Abundance determined using fluorescent insitu hybridisation using universal bacterial probe EUB338, alphaproteobacteria, gammaproteobacteria and flavobacteria specific probe. Total count of bacteria was determined by epifluorescence using DAPI. Details of sites analysed are included in the seawater sample file. File 6. Nutrient and chlorophyll a data for samples studied (see seawater sample file) including nitrate, phosphate and silica. File 7. Bacterial isolate information including strain designations, site location, and identification to genus level. File 8. . Bacterial isolate fatty acid data for strains designated as novel in bacterial isolate information file. Fatty acids determined using GC-MS analytical methods. File 9. Bacterial isolate phenotypic data for strains designated as novel in bacterial isolate information file. Includes morphological, physicochemical, biochemical and nutritional profile data. Part 2: Total of 4 files: File 1. 16S rRNA gene sequences derived from denaturing gradient gel electrophoretic (DGGE) gel slices via extraction, PCR and cloning. DGGE analysis performed on samples analysed over 30 days from 20 litre microcosms derived from southern seawater to which was added 10 mg sterile diatom detritus derived from axenic Nitszchia closterium. Sequences are all deposited in the GenBank nucleotide database and are in FASTA format. File 2. Flavobacteria abundance in Southern Ocean seawater microcosms over 30 days. Abundance determined using real-time PCR using universal bacterial and flavobacteria specific PCR primers. File 3. Bacterial mediated silica release data from Southern Ocean seawater microcosms over 30 days. Includes non-detritus amended controls that indicate the natural level of of seawater silica. Silica analysis performed by a chemical procedure. File. 4. Seawater sample data obtained during 2001 indicating the sites for seawater used for creating 20 l microcosms and used to assess silica release by bacteria from diatom detritus.

  • Elephant seals use a suite of physiological and behavioural mechanisms to maximise the time they can be submerged. Of these hypo-metabolism is one of the most important, so this study quantified maximum O2 consumptions relative to dove depth and swim speed. From the abstract of the referenced paper: Heart rate, swimming speed, and diving behaviour were recorded simultaneously for an adult female southern elephant seal during her postbreeding period at sea with a Wildlife Computers heart-rate time depth recorder and a velocity time depth recorder. The errors associated with data storage versus real-time data collection of these data were analysed and indicated that for events of short duration (i.e., less than 10 min or 20 sampling intervals) serious biases occur. A simple model for estimating oxygen consumption based on the estimated oxygen stores of the seal and the assumption that most, if not all, dives were aerobic produced a mean diving metabolic rate of 3.64 mL O2 kg-1, which is only 47% of the field metabolic rate estimated from allometric models. Mechanisms for reducing oxygen consumption while diving include cardiac adjustments, indicated by reductions in heart rate on all dives, and the maintenance of swimming speed at near the minimum cost of transport for most of the submerged time. Heart rate during diving was below the resting heart rate while ashore in all dives, and there was a negative relationship between the duration of a dive and the mean heart rate during that dive for dives longer than 13 min. Mean heart rates declined from 40 beats min-1 for dives of 13 min to 14 beats min-1 for dives of 37 min. Mean swimming speed per dive was 2.1 m s-1, but this also varied with dive duration. There were slight but significant increases in mean swimming speeds with increasing dive depth and duration. Both ascent and descent speeds were also higher on longer dives. Data were collected on Time Depth Recorders (TDRs), and stored in hexadecimal format. Hexadecimal files can be read using 'Instrument Helper', a free download from Wildlife Computers (see the provided URL). Data for this project is the same data that was collected for ASAC projects 769 and 589 (ASAC_769 and ASAC_589).

  • Metadata record for data from ASAC Project 933 See the link below for public details on this project. Australian Antarctic and Southern Ocean Profiling Project (AASOPP) was the outcome of a government decision in 1999 that it would carry out the necessary work to place Australia in a position to be able to prepare a submission defining the outer limit the 'extended Continental Shelf' (ECS) off the Australian Antarctic Territory (AAT). The ECS is the area of seabed/subsoil jurisdiction extending beyond the 200 nautical mile Exclusive Economic Zone, and is defined by Article 76 of the United Nations Convention on the Law of the Sea. AASOPP was set up in 2000, under the management of the Department of Finance and Administration and in consultation with the Australian Antarctic Division, to undertake the acquisition and interpretation of the data that would underpin a UN submission. Technical aspects of the work were largely the responsibility of the Australian Geological Survey Organisation and the Australian Surveying and Land Information Group (later Geoscience Australia). Marine geophysical surveys were conducted in 2001/2 and 2002/3 by the primary contractors, FUGRO Geoteam supervised by AGSO (Geoscience Australia) using the vessels Geoarctic and Polar Duke (survey numbers GA227, GA228 and GA229). Data collected were seismic reflection, sonobuoy seismic refraction, magnetic and gravity profiles. Data processing was supervised by Geoscience Australia where they are archived. Seismic data were lodged with the SCAR Seismic Data Library. Law of the Sea interpretations were lodged as part of the Australian submission to the United Nations by November, 2004 with a request not to examine the Antarctic case until requested.

  • Environmental variables in the region of the Kerguelen Plateau compiled from different sources and provided in the ascii raster format. Mean surface and seafloor temperature, salinity and their respective amplitude data are available on the time coverage 1955-2012 and over five decades: 1955 to 1964, 1965 to 1974, 1975 to 1984, 1985 to 1994 and 1995 to 2012. N/A was set as the no data reference. Future projections are provided for several parameters: they were modified after the Bio-ORACLE database (Tyberghein et al. 2012). They are based on three IPCC scenarii (B1, AIB, A2) for years 2100 and 2200 (IPCC, 4th report).

  • This dataset contains records of ice thickness and snow thickness from Casey, Antarctica. Measurements were attempted on a weekly basis and were recorded between 1979 and 1992. The observations are not continuous however. The dataset is available via the provided URL. This data were also collected as part of ASAC projects 189 and 741. The Casey fast ice thickness data are no longer being collected.