Geoscience Australia marine reconnaissance survey TAN0713 to the Lord Howe Rise offshore eastern Australia was completed as part of the Federal Government¿s Offshore Energy Security Program between 7 October and 22 November 2007 using the New Zealand Government¿s research vessel Tangaroa. The survey was designed to sample key, deep-sea environments on the east Australian margin (a relatively poorly-studied shelf region in terms of sedimentology and benthic habitats) to better define the Capel and Faust basins, which are two major sedimentary basins beneath the Lord Howe Rise. Samples recovered on the survey contribute to a better understanding of the geology of the basins and assist with an appraisal of their petroleum potential. They also add to the inventory of baseline data on deep-sea sediments in Australia. The principal scientific objectives of the survey were to: (1) characterise the physical properties of the seabed associated with the Capel and Faust basins and Gifford Guyot; (2) investigate the geological history of the Capel and Faust basins from a geophysical and geological perspective; and (3) characterise the abiotic and biotic relationships on an offshore submerged plateau, a seamount, and locations where fluid escape features were evident. This dataset comprises total oxygen uptake and total carbon fluxes from core incubation experiments. Some relevant publications which pertain to these datasets include: 1. Heap, A.D., Hughes, M., Anderson, T., Nichol, S., Hashimoto, T., Daniell, J., Przeslawski, R., Payne, D., Radke, L., and Shipboard Party, (2009). Seabed Environments and Subsurface Geology of the Capel and Faust basins and Gifford Guyot, Eastern Australia ¿ post survey report. Geoscience Australia, Record 2009/22, 166pp. 2. Radke, L.C. Heap, A.D., Douglas, G., Nichol, S., Trafford, J., Li, J., and Przeslawski, R. 2011. A geochemical characterization of deep-sea floor sediments of the northern Lord Howe Rise. Deep Sea Research II 58: 909-921

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.

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.

No abstract available

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.

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It is with great interest that we read the paper by Mueller (2015) who proposes that the majority of small pockmarks with diameters less than about 10 m on the northwest shelf of Australia may be of biotic origin, created by the fish Epinephelus, the Grouper. This hypothesis is based on a spatial association between pockmarks and Epinephelus at a number of sites on the northwest shelf and elsewhere around Australia, and on recent work undertaken on the habitats and observed behaviours of grouper fish in the Gulf of Mexico who excavate sediment from pre-existing solution cavities (Coleman et al., 2010; Wall et al., 2011). However, we contend that critical details have not been taken into account as part of Mueller's (2015) hypothesis, and additional consideration of existing geologic, geomorphic, sedimentologic and geochemical information is required. To make the science more robust, here we present a more comprehensive overview of the information available.

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As part of Geoscience Australia's commitment towards the National Environmental Programme's Marine Biodiversity Hub, we have developed a fully four-dimensional (3D x time) Lagrangian biophysical dispersal model to simulate the movement of marine larvae over large, topographically complex areas. The model operates by fusing the results of data-assimilative oceanographic models (e.g. BLUELink, HYCOM, ROMS) with individual-based particle behaviour. The model uses parallel processing on Australia's national supercomputer to handle large numbers of simulated larvae (on the order of several billion), and saves positional information as points within a relational database management system (RDBMS). The model was used to study Australia's northwest marine region, with specific attention given to connectivity patterns among Australia's north-western Commonwealth Marine Reserves and Key Ecological Features (KEFs). These KEFs include carbonate terraces, banks and reefs on the shelf that support diverse benthic assemblages of sponges and corals, and canyons that extend from the shelf edge to the continental slope and are potential biodiversity hotspots. We will show animations of larval movement near canyons within the Gascoyne CMR; larval dispersal probability clouds partitioned by depth and time; as well as matrices of connectivity values among features of interest. We demonstrate how the data can be used to identify connectivity corridors in marine environments, and how the matrices can be analysed to identify key connections within the network. Information from the model can be used to inform priorities for monitoring the performance of reserves through examining net contributions of different reserves (i.e. are they sources or sinks), and studying changes in connectivity structure through adding and removing reserve areas.

The shallow-water (<160m) marine environment around the Australian research station, Casey station (east Antarctica) is a high use area, frequently visited by both large resupply vessels and smaller workboats conducting scientific research in the area, yet high resolution modern bathymetric data in the area, as well as much of the east Antarctic continental margin, is limited. The Casey area hosts significant levels of biodiversity, but this knowledge is geographically restricted in scope (i.e. shallow depths, close to shore). This biodiversity faces pressures from human activities and effects of climate change, yet extensive knowledge gaps remain, limiting efforts to conserve and manage it effectively. Improved bathymetric surveying in this region will begin to fill these knowledge gaps by conducting representative sampling of both the physical environment and biological communities and reduce the risk to maritime operations in the region. During the period December 2014 to February 2015, a collaborative multibeam survey (Australian Antarctic Division, Royal Australian Navy and Geoscience Australia) was conducted in the shallow-water near-shore regions adjacent to Casey station and covered an area of ca. 28 km2. The survey employed Geoscience Australia's KONGSBERG EM3002 dual head sonar system mounted on an Australian Antarctic Division supplied science workboat, the RV Howard Burton. In total, the surveyed region covered ca. 34 km2, to a maximum depth of ca. 170m. The data was processed in CARIS v8 and a seafloor surface has been gridded at a resolution of 1m. Preliminary field-based interpretation of the submarine geomorphology reveal several dominant geomorphological features which can be simplified into 4 domains as follows: (1) NW and WSW trending fault and channel systems, (2) glacio-fluvial seafloor features (possible terminal moraines) within channel features, (3) bedrock basement highs and (4) `deep isolated basins.