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EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES

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  • Metadata record for data from ASAC Project 668 See the link below for public details on this project. From the abstracts of some of the referenced papers: Body shrinkage may be one of the strategies that Antarctic krill use to cope with food scarcity, particularly during winter. Despite their demonstrated ability to shrink, there are only very limited data to determine how commonly shrinkage occurs in the wild. It has been previously shown that laboratory-shrunk krill tend to conserve the shape of the eye. This study examined whether the relationship between the eye diameter and body length could be used to detect whether krill had been shrinking. By tracking individuals over time and examining specimens sampled as groups, it was demonstrated that fed and starved krill are distinguishable by the relationship between the eye diameter and body length. The eye diameter of well-fed krill continued to increase as overall length increased. This created a distinction between fed and starved krill, while no separation was detected in terms of the body length to weight relationship. Eye growth of krill re-commenced with re-growth of krill following shrinkage although there was some time lag. It would take approximately 2 moult cycles of shrinkage at modest rates to significantly change the eye diameter to body length relationship between normal and shrunk krill. If krill starve for a prolonged period in the wild, and hence shrink, the eye diameter to body length relationship should be able to indicate this. This would be particularly noticeable at the end of winter. A series of experiments was carried out to examine the relationship between feeding, moulting, and fluoride content in Antarctic krill (Euphausia superba). Starvation increased the intermolt period in krill, but had no effect on the fluoride concentration of the moults produced. Addition of excess fluoride to the sea water had no direct effect on the intermoult period, the moult weight, or moult size. Additions of 6 micrograms per litre and 10 micrograms per litre fluoride raised the fluoride concentrations of the moults produced and the whole animals. The whole body fluoride content varied cyclically during the moult cycle, reaching a peak 6 days following ecdysis. Fluoride loss at ecdysis could largely be explained by the amount of this ion shed in the moult.

  • 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.

  • Refer to antFOCE report section 4.5.1 for deployment, sampling and analysis details. https://data.aad.gov.au/metadata/records/AAS_4127_antFOCE_Project4127 The download file contains an Excel workbook with one data spreadsheet and one of notes relevant to the data. The data are the total number of each motile organism collected from 2 recruitment tiles deployed in chambers or open plots during the antFOCE experiment. The 2 tiles were deployed together in a metal stand in either a horizontal or vertical orientation. Background The antFOCE experimental system was deployed in O’Brien Bay, approximately 5 kilometres south of Casey station, East Antarctica, in the austral summer of 2014/15. Surface and sub-surface (in water below the sea ice) infrastructure allowed controlled manipulation of seawater pH levels (reduced by 0.4 pH units below ambient) in 2 chambers placed on the sea floor over natural benthic communities. Two control chambers (no pH manipulation) and two open plots (no chambers, no pH manipulation) were also sampled to compare to the pH manipulated (acidified) treatment chambers. Details of the antFOCE experiment can be found in the report – “antFOCE 2014/15 – Experimental System, Deployment, Sampling and Analysis”. This report and a diagram indicating how the various antFOCE data sets relate to each other are available at: https://data.aad.gov.au/metadata/records/AAS_4127_antFOCE_Project4127

  • Metadata record AAS_4127_antFOCE_HardSubstrateFauna contains all data sets relating to the fauna sampled from hard substrates during the antFOCE experiment, including recruitment tiles, artificial substrate units and biofilm slides. Refer to antFOCE report section 4.5 for deployment, sampling and on-station analysis details. https://data.aad.gov.au/metadata/records/AAS_4127_antFOCE_Project4127 Background The antFOCE experimental system was deployed in O’Brien Bay, approximately 5 kilometres south of Casey station, East Antarctica, in the austral summer of 2014/15. Surface and sub-surface (in water below the sea ice) infrastructure allowed controlled manipulation of seawater pH levels (reduced by 0.4 pH units below ambient) in 2 chambers placed on the sea floor over natural benthic communities. Two control chambers (no pH manipulation) and two open plots (no chambers, no pH manipulation) were also sampled to compare to the pH manipulated (acidified) treatment chambers. Details of the antFOCE experiment can be found in the report – “antFOCE 2014/15 – Experimental System, Deployment, Sampling and Analysis”. This report and a diagram indicating how the various antFOCE data sets relate to each other are available at: https://data.aad.gov.au/metadata/records/AAS_4127_antFOCE_Project4127

  • The broadscale distribution of flora (lichens, mosses, non-marine algae)and fauna (penguins, flying birds, seals)in the Stillwell Hills was mapped using GPS technology. Samples of flora were collected for taxonomic identification. Data were recorded and catalogued in shapefiles.

  • Refer to antFOCE report section 4.4.1 for deployment, sampling and analysis details. https://data.aad.gov.au/metadata/records/AAS_4127_antFOCE_Project4127 The download file contains an Excel workbook with 2 data spreadsheets - one for the greater than 1mm fraction and one for the 0.5mm to 1mm fraction of the macrofauna - and a third of notes relevant to the data. The data are the total number of each organism collected from sediment cores taken in and adjacent to chambers or open plots during the antFOCE experiment. Analysis methods are detailed in the Notes spreadsheet. Background The antFOCE experimental system was deployed in O’Brien Bay, approximately 5 kilometres south of Casey station, East Antarctica, in the austral summer of 2014/15. Surface and sub-surface (in water below the sea ice) infrastructure allowed controlled manipulation of seawater pH levels (reduced by 0.4 pH units below ambient) in 2 chambers placed on the sea floor over natural benthic communities. Two control chambers (no pH manipulation) and two open plots (no chambers, no pH manipulation) were also sampled to compare to the pH manipulated (acidified) treatment chambers. Details of the antFOCE experiment can be found in the report – “antFOCE 2014/15 – Experimental System, Deployment, Sampling and Analysis”. This report and a diagram indicating how the various antFOCE data sets relate to each other are available at: https://data.aad.gov.au/metadata/records/AAS_4127_antFOCE_Project4127

  • Metadata record for data from ASAC Project 2897 See the link below for public details on this project. Public The aim of this multi-disciplinary proposal is to examine the molecular evolution of toxic proteins across the full taxonomical spectrum of venomous Antarctic marine animals. The project will create a comparative encyclopedia of the evolution of the venom system in the Antarctic marine animal kingdom and elucidate the underlying structure-function relationships between these toxic proteins. Through a process utilising cutting edge analytical techniques, such as cDNA cloning and molecular modelling, a feedback loop of bioactivity testing will be created to contribute substantially towards the area of drug design and development from toxic animal peptides. Project objectives: The aim of this project is to investigate the evolution of the molecular, structural and functional properties of Antarctic marine animal venom systems. This integrative project aims to investigate the origin and evolution of secreted proteins in the venom glands of toxic polar animals by means of: - Analysis of mechanisms of evolution in multigene families. - Phylogenetic analysis of evolutionary relationships among secreted proteins in the venom glands of major lineages; - Search for correlations between: (i) evolution of venom gland structure (ii) molecular evolution of venom components, and (iii) ecological specialisation of the animal - Bioactivity studies will be conducted upon representative purified or synthesised proteins. - A first ever comparison of the convergent strategies between Arctic and Antarctic endemic fauna. The results will help us to understand protein evolution, will cast light on the classic problem of how venom systems evolve, and may provide leads in the search for commercially-exploitable venom proteins. Taken from the 2008-2009 Progress Report: Progress against objectives: We have completed the genetic analyses of the specimens and sequence analyses. Phylogenetic positioning is robust other than a few deep level nodes. We are undertaking a second round of genetic analyses using different primers in order to resolve these nodes. Biochemical analyses of crude protein secretions from the posterior salivary (venom) glands has revealed temperature specific modifications of some of the venom components to adapt them to the polar conditions. We have tested the secretions in a battery of assays. We are now repeating those assays using purified proteins in order to determine which types are responsible for particular effects and also investigate synergistic interactions. Taken from the 2009-2010 Progress Report: Progress against objectives: We have undertaken genetic analyses of the specimens collected, and investigated specific adaptations of their venom systems. Results to-date include: - Antarctic octopuses are more genetically diverse than previously appreciated, including at least one new genus - an inverse relationship exists between the size of the venom gland and the size of the beak - their venoms have undergone temperature-specific adaptations

  • Percent-cover estimates from forward facing still-images collected during the benthic trawls of the 2007/08 CEAMARC voyage (raw data-set here: https://data.aad.gov.au/metadata/records/CEAMARC_CASO_200708_V3_IMAGES). All fauna in the bottom third of each image was scored to the lowest taxonomic resolution possible. The images originate from 32 transects, but were split by their lon-lat-position within a spatial grid of environmental variables into 41 sites. This dataset contains: (1) - species/ morphotypes identified to the highest taxonomic resolution possible - broader taxonomic classification (phylum/class) - each species mobility, feeding-type and body-shape if possible - average abundances in percent-cover at each site (2) - the mean longitude of all images aggregated per site - the mean latitude of all images aggregated per site - the number of images scored per site

  • This data were collected on the sixth Nella Dan voyage of a long term field survey project being conducted by the Australian Antarctic Division, to collect distribution, abundance and population structure data for the krill Euphausia superba in the Prydz Bay region, Antarctica. This voyage, the Australian Antarctic Marine Biological Ecosystem Research 1986/1987 (AAMBER 86/87) cruise, operated between February and April 1987. During March, a survey of the krill population and zooplankton community was conducted, to determine the late summer distribution and abundance of krill, especially the larvae. This was done as a follow up to SIBEX II in mid-summer (Janurary) 1985. The major species investigated were Euphausia superba, Euphausia frigidia, Euphausia crystallorophias and Thysanoessa marcuria. Phytoplankton pigment analysis was also conducted at each CTD station site.

  • The dataset contains raster files (.grd) for food-availability and predicted distribution of suspension feeder abundances averaged across a five year time-period before (2005-2009) and after (2011-2016) the calving of the Mertz Glacier Tongue in 2010. The following data are included: - sinking, settling and horizontal flux of food-particles along the seafloor - suspension feeder abundances and standard deviation of the predicted distribution All data has been generated as part of the paper: Jansen et al. (2018) Mapping Antarctic suspension feeder abundances and seafloor-food availability, and modelling their change after a major glacier calving. Frontiers in Ecology and Evolution