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 resource contains multibeam sonar backscatter data for the continental shelf area of Flinders Commonwealth Marine Reserve, northeast Tasmania. Multibeam data were collected by Geoscience Australia and University of Tasmania in May 2011 (survey GA0331) and June-July 2012 (survey GA0337) on RV Challenger. The survey used a Kongsberg EM3002 300 kHz multibeam sonar system mounted in single head configuration to broadly classify the seabed into hard (bedrock reef), soft (sedimentary) and mixed substrate types at select locations across the shelf. The 2011 survey involved reconnaissance mapping along a series of cross-shelf transects, covering a total of 767 line km. For the 2012 survey, multibeam data (bathymetry and backscatter) were collected at 40 pre-determined stations, each covering an area approximately 200 x 200 m. The location of stations was selected using a Generalised Random Tessellation Stratified (GRTS) sampling design that ensured an even spatial distribution of sites. Multibeam data was also collected along transits between GRTS stations (410 line km) and across a 30 km2 area of the outer shelf, incorporating areas of low profile reef, sandy shelf and three shelf-incising canyon heads. Backscatter data are gridded to 2 m spatial resolution. The 2012 survey also included seabed observations at the 40 GRTS stations using a drop camera and collection of sediment samples at 31 stations using a Shipek grab. The Flinders CMR survey was a pilot study undertaken in 2012 as part of the National Marine Biodiversity Hub's National Monitoring Evaluation and Reporting Theme. The aim of this theme is to develop a blueprint for the sustained monitoring of the South-east Commonwealth Marine Reserve Network, specifically; 1) to contribute to an inventory of demersal and epibenthic conservation values in the reserve and 2) to test methodologies and deployment strategies in order to inform future survey design efforts. Several gear types were deployed; including multibeam sonar, shallow-water (less than 150m) Baited Remote Underwater Video Systems (BRUVS), deep- water BRUVS (to 600 m), towed video and digital stereo stills. Embargo statement: Resource embargoed pending completion of NERP research. Release date 31 December 2014. Attribution statement: Data was sourced from the NERP Marine Biodiversity Hub. The Marine Biodiversity Hub is supported through funding from the Australian Government's National Environmental Research Program (NERP), administered by the Department of Sustainability, Environment, Water, Population and Communities (DSEWPAC). Dataset name: National Environmental Research Program (NERP) Marine Biodiversity Hub, 2012, Flinders Commonwealth Marine Reserve Shelf Backscatter

This product is for in-house use only. It is a back up of a hard drive from the former Seabed Mapping and Characterisation section and contains working files from a variety of marine surveys and other projects dating from 2009 and before. Files were copied exactly as they appeared on the external Seagate hard drive.

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.

A biophysical dispersal model was used to simulate hydrodynamic connectivity among canyons located within Australia's South-west marine region. The results show that exchange among canyons in this area is greatly influenced by the Leeuwin current, transporting larvae in a unidirectional manner around Cape Leeuwin, and continuing eastwards along the Great Australian Bight. Larvae within canyons tend to remain within them, however if they are transported above the canyon walls, they then have the opportunity to be transported significant distances (thousands of kilometres). Analysis of the variability in connectivity patterns reveals concentrated flow near the shelf break, with increasing levels of variability leading offshore from the canyons. While the average potential flow distance and duration between canyons were approximately 550 kilometres and 33 days respectively, the average realized flow distance and duration were approximately 30 kilometres and 6 days respectively. This study provides the first consideration of connectivity among submarine canyons and will help improve management of these features by providing a better understanding of larval movement, transboundary exchange and the potential spread of invasive species.

Geoscience Australia completed an underwater towed video survey (GA survey 0338) of the Shelf Rocky Reefs Key Ecological Feature (KEF) in the vicinity of the Solitary Islands in collaboration with the New South Wales Office of Environment and Heritage on the R.V. Bombora between 7 - 16 August 2012. The aim of the survey was to characterize benthic habitat in areas of the KEF, and to compare and contrast the effectiveness of different methods for capturing visual representations of biological communities. The survey collected forward-facing mono video, forward-facing stereo video, and downward facing stills along 12 transects, each of 2 km length. The geographic position of the vessel was determined using a GPS system, and the location of the towed camera body was recorded using a USBL system. The KEF survey was part of the National Marine Biodiversity Hub's National Monitoring Evaluation and Reporting Theme. The aim of this theme is to develop a blueprint for the sustained monitoring of the Commonwealth Marine Reserve Network, specifically; 1) to contribute to an inventory of demersal and epibenthic conservation values in the KEF and; 2) to test methodologies and deployment strategies in order to inform future survey design efforts. Embargo statement: Resource embargoed pending completion of NERP research. Release date 31 December 2014 Attribution statement: Users of NERP Marine Biodiversity Hub data are required to clearly acknowledge the source of the material in the format: "Data was sourced from the NERP Marine Biodiversity Hub" the Marine Biodiversity Hub is supported through funding from the Australian Government's National Environmental Research Program (NERP), administered by the Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC)." Dataset name: National Environmental Research Program (NERP) Marine Biodiversity Hub, 2012, Flinders Commonwealth Marine Reserve Shelf Backscatter

Submarine canyons are highly energetic and dynamic environment. Owing to their abrupt and complex topographies that are contrast to the adjacent shelf and slope, they can generate intense mixing, both horizontally through internal tides and waves and vertically through upwelling and downwelling. Complex hydrodynamic processes and increased food supply in sediment and water column result in elevated primary and secondary production which would favour the development of a highly productive and temporally dynamic food web over the canyons. Consequently, many submarine canyons, especially those incise into continental shelf, are considered as biodiversity hotspots. To better understand the ecosystem functions and ecological processes of marine environment, identification and classification of submarine canyons are needed. This study developed a national-scale submarine canyon classification system for Australian ocean based on canyon's physical characteristics. A hierarchical classification scheme was proposed. At the top level, the submarine canyons were classified into shelf-incising canyons and confined-to-slope canyons. At the lower levels, the canyons were classified on their morphometry, shape and location characteristics separately. Accurate identification of submarine canyons was the critical first step for the success of the proposed canyon classification system. A national bathymetry data at a spatial resolution of 250 metres and a completed set of multibeam bathymetry data at a spatial resolution of 50 metres from all previous multibeam surveys, both published by Geoscience Australia, were used. Hill-shaded layers were generated from which most submarine canyons could be easily identified. The extents of individual canyons, from wall to wall, were manually digitised as a GIS polygon layer. The initial number of canyons was then filtered using the following criteria: - Depth of the canyon head is less than 4000 m, - Depth range between the canyon's head and foot is greater than 600 m, and - Incision of the canyon head is greater than 100 m. At the lower levels, the following metrics were calculated as the inputs to the canyon classifications: - Morphometry metrics: incision depth of the canyon head, standard deviation of the slope gradient (within all cells in a canyon), slope gradient between the canyon head and the canyon foot, and canyon overall rugosity. - Shape metrics: canyon area, number of branches, length/width ratio of the smallest bounding rectangle, border index, compactness and canyon volume. - Location metrics: depth of the canyon head, depth range between the canyon's head and foot, canyon density, distance to coast, distance to the shelf break, incision depth (shelf-incising canyons only), and incision area (shelf-incising canyons only). The hierarchal agglomerative clustering technique was used for the unsupervised classifications. After the filtering, a total of 708 submarine canyons were identified for the entire Australian EEZ. Among these 708 canyons, 134 of them incise into continental shelf; the rest are confined in continental slope. For the shelf-incising canyons, the morphometry, shape and location based classifications all resulted in three classes. Combining the three lower level classifications yielded 15 classes. For the slope-confined canyons, the morphometry, shape and location based classifications resulted in three, four and four classes, respectively. Combining the three lower level classifications yielded 37 classes. GeoHab 2013

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.

Bathymetric flythrough of the Southeast Margin of Australia for a Powerpoint presentation on the Marine Geoscience capabilities of the RV Investigator. The presentation will be given at the Welcome to Port Ceremony for the ship.

A fully four-dimensional (3D x time) open source (BSD-3), object-oriented biophysical dispersal model was developed to simulate the movement of marine larvae over semi-continuous surfaces. The model is capable of handling massive numbers of simulated larvae, can accommodate diverse life history patterns and distributions of characteristics, and saves point-level information to a relational database management system. The model was used to study Australia's northwest marine region, with attention given to connectivity patterns among Australia's north-western Commonwealth Marine Reserves (CMRs). This work was supported by the Marine Biodiversity Hub through the Australian Government's National Environmental Research Program (NERP).