This dataset contains species identifications of sponges collected during survey SOL4934 (R.V. Solander, 27 August - 24 September, 2009). Animals were collected from the Joseph Bonaparte Gulf with a benthic sled. Specimens were lodged at Northern Territory Museum on the 26 September 2009. Species-level identifications were undertaken by Belinda Glasby at the Northern Territory Museum and were delivered to Geoscience Australia on the 23 February 2011. See GA Record 2010/09 for further details on survey methods and specimen acquisition. Data is presented here exactly as delivered by the taxonomist, and Geoscience Australia is unable to verify the accuracy of the taxonomic identifications.

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This dataset contains species identifications of benthic worms collected during survey TAN0713 (R.V. Tangaroa, 7 Oct - 22 Nov 2007). Animals were collected from the Faust and Capel basins and Gifford Guyot with a boxcore, rock dredge, or epibenthic sled. Specimens were lodged at Museum of Victoria in June 2008. Species-level identifications were undertaken by Robin Wilson at the Museum of Victoria and were delivered to Geoscience Australia on 1 Aug 2008. See GA Record 2009/22 for further details on survey methods and specimen acquisition. Data is presented here exactly as delivered by the taxonomist, and Geoscience Australia is unable to verify the accuracy of the taxonomic identifications.

Geoscience Australia has been updating its collection of navigation for marine surveys in Australia. These include original navigation files, the 2003 SNIP navigation files and survey track maps along with survey acquisition reports. The result will be an updated cleansed navigation collection. The collection is based on the standard P190 extended header navigation file which follows the UKOOA standard. Industry standard metadata associated with a seismic survey is preserved. To assist industry, Geoscience Australia is making available its updated version of cleansed navigation. Although the process of updating the navigation data is ongoing and there is still legacy data to check, the navigation data is at point where a significant improvement has been achieved and it is now usable. Users should be aware that this navigation is not final and there may be errors. The KML file can be viewed using a range of applications including Google Earth, NASA WorldWind, ESRI ArcGIS Explorer, Adobe PhotoShop, AutoCAD3D or any other earth browser (geobrowser) that accepts KML formatted data. Alternatively the Shapefiles can be downloaded and viewed using any application that supports shape files.

This dataset contains species identifications of echinoderms collected during survey GA2476 (R.V. Solander, 12 August - 15 September 2008). Animals were collected from the Western Australian Margin with a BODO sediment grab or rock dredge. Specimens were lodged at Museum of Victoria on the 10 March 2009. Species-level identifications were undertaken by Tim O'Hara at the Museum of Victoria and were delivered to Geoscience Australia on the 24 April 2009. See GA Record 2009/02 for further details on survey methods and specimen acquisition. Data is presented here exactly as delivered by the taxonomist, and Geoscience Australia is unable to verify the accuracy of the taxonomic identifications.

The Leeuwin Current has significant ecological impact on the coastal and marine ecosystem of south-western Australia. This study investigated the spatial and temporal dynamics of the Leeuwin Current using monthly MODIS SST dataset between July 2002 and December 2012. Topographic Position Index layers were derived from the SST data for the mapping of the spatial structure of the Leeuwin Current. The semi-automatic classification process involves segmentation, 'seeds' growing and manual editing. The mapping results enabled us to quantitatively examine the current's spatial and temporal dynamics in structure, strength, cross-shelf movement and chlorophyll a characteristic. It was found that the Leeuwin Current exhibits complex spatial structure, with a number of meanders, offshoots and eddies developed from the current core along its flowing path. The Leeuwin Current has a clear seasonal cycle. During austral winter, the current locates closer to the coast (near shelf break), becomes stronger in strength and has higher chlorophyll a concentrations. While, during austral summer, the current moves offshore, reduces its strength and chlorophyll a concentrations. The Leeuwin Current also has notable inter-annual variation due to ENSO events. In El Niño years the current is likely to reduce strength, move further inshore and increase its chlorophyll a concentrations. The opposite occurs during the La Niña years. In addition, this study also demonstrated that the Leeuwin Current has a significantly positive influence over the regional nutrient characteristics during the winter and autumn seasons. Apart from surface cooling and advection, the Leeuwin Current's sizable cross-shelf movement may be another contributing factor to the seasonal and inter-annual variations of its chlorophyll a concentrations.

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Fisheries groups worldwide are concerned that seismic operations negatively affect catch rates within a given area, although there is a lack of field-based scientific evidence. In southeast Australia, marine seismic surveys have been blamed for mass mortalities of benthic invertebrates including the commercial scallop Pecten fumatus. Geoscience Australia conducted a 2-D seismic survey in this region in April 2015, thereby presenting an opportunity to conduct field-based experiments investigating the potential impacts on marine organisms. Moored hydrophones recorded noise before and during the seismic survey. An Autonomous Underwater Vehicle (AUV) was used to evaluate the effectiveness of seafloor images to support scallop monitoring. In addition, more traditional sampling was undertaken using a commercial scallop dredge from which a variety of biological and biochemical variables were analysed. The AUVs and dredge were deployed at three time periods (before the seismic survey, 2 months after seismic operations ceased, 10 months after seismic operations ceased), although poor-quality AUV images acquired before the survey precluded the analysis of these data. The highest sound exposure level recorded by the hydrophones was 146 dB re 1 µPa2s at 51 m water depth, at a distance of 1.4 km from the airguns. Commercial scallops were not abundant in the study area, and analysis of AUV images revealed no differences in commercial scallop types (live, clapper, dead shell, other) between experimental and control zones. Similarly, analysis of dredged scallops shows no detectable impact due to seismic activity on shell size, meat size and condition, gonad size and condition, and biochemical indices. Both AUV and dredging data showed strong spatial patterns, with significant differences between sites. Our study confirms previous work showing no evidence of immediate mortality on scallops in the field, and it expands this to include no evidence of long-term or sub-lethal effects. Negative impacts are currently confined to laboratory settings with unrealistic sound exposures. If short-term effects are investigated, we recommend a focus on the underlying mechanisms of potential impacts (i.e. physiological responses), rather than gross metrics such as mortality or size. Physiological responses to airgun sound may not be as immediately obvious as mortality or behavioural responses, but they are equally important to provide early indications of negative effects, as well as to explain the underlying mechanisms behind mortality events and reduced catch.

This dataset contains species identifications of macro-benthic worms collected during survey SOL4934 (R.V. Solander, 27 August - 24 September, 2009). Animals were collected from the Joseph Bonaparte Gulf with a benthic sled or a Smith-McIntyre grab. Specimens were lodged at Northern Territory Museum on the 24 September 2009. Species-level identifications were undertaken by Chris Glasby at the Northern Territory Museum and were delivered to Geoscience Australia on the 26 October 2009 See GA Record 2010/09 for further details on survey methods and specimen acquisition. Data is presented here exactly as delivered by the taxonomist, and Geoscience Australia is unable to verify the accuracy of the taxonomic identifications.

Life in icy waters: A geoscience perspective of life on the Antarctic seafloor