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Geoscience Australia carried out marine surveys in southeast Tasmania in 2008 and 2009 (GA0315) to map seabed bathymetry and characterise benthic environments through observation of habitats using underwater towed video. Data was acquired using the Tasmania Aquaculture and Fisheries Institute (TAFI) Research Vessel Challenger. Bathymetric mapping was undertaken in seven survey areas, including: Freycinet Pensinula (83 sq km, east coast and shelf); Tasman Peninsula (117 sq km, east coast and shelf); Port Arthur and adjacent open coast (17 sq km); The Friars (41 sq km, south of Bruny Island); lower Huon River estuary (39 sq km); D Entrecastreaux Channel (7 sq km, at Tinderbox north of Bruny Island), and; Maria Island (3 sq km, western side). Video characterisations of the seabed concentrated on areas of bedrock reef and adjacent seabed in all mapped areas, except for D Entrecastreaux Channel and Maria Island. The "challenger" folder contains processed multibeam backscatter data of the South East Tasmania Shelf. The SIMRAD EM3002 multibeam backscatter data were processed using the CMST_GA MB Process, a multibeam processing toolbox codeveloped by Geoscience Australia and Curtin University of Technology.

This dataset contains the sea surface temperature data derived from the MODIS Terra sensor, the chlorophyll data derived from the SeaWIFS satellite, and the K490 data derived from the SeaWIFS satellite. Ocean temperature is a useful indicator of the type of marine life that could be found at a particular location. Many marine plants and organisms have a relatively narrow range of tolerance for temperature, and will either perish or be out-competed where temperatures are outside their comfort zone. Chlorophyll a is a plant pigment which provides a measurement of the biomass (or quantity) of plants. In the water column, it is a measure of the suspended (or planktonic) biomass of single-celled microscopic plants. Chlorophyll is a commonly used measure of water quality. K490 indicates the turbidity of the water column; the depth to which the visible light in the blue-green region of the spectrum penetrates the water column. It is directly related to the presence of particles in the water column. Turbidity has consequences for benthic marine life, ranging from the availability of light to the quantity of nutrients in the water column. The datasets contain 6 grids. Two for each variable: mean and standard deviation. Please see the metadata for detailed information.

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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.

Submarine canyons have been recognised as areas of significant ecological and conservation value. In Australia, 713 canyons were mapped and classified in terms of their geomorphic properties. Many of them are identified as Key Ecological Features (KEFs) and protected by Commonwealth Marine Reserves (CMRs) using expert opinion based on limit physical and ecological information. The effectiveness of these KEFs and CMRs to include ecologically significant submarine canyons as prioritised conservation areas needs to be objectively examined. This study used two local-based spatial statistical techniques, Local Moran's I (LMI) and the Gi* statistic, to identify hotspots of Australian canyons (or unique canyons) for conservation priority. The hotspot analysis identified 29 unique canyons according to their physical attributes that have ecological relevance. Most of these unique physical canyons are distributed on the southern margins. Twenty-four of the 29 canyons are enclosed by the existing KEFs and protected by CMRs to varied extents. In addition, the hotspot analysis identified 79 unique canyons according to their chlorophyll a concentrations, all of which are located in the South-east marine planning region. The findings can be used to update or revise the profile descriptions for some existing KEFs. In future, if the boundaries of these KEFs are deemed necessary to be reviewed, the new information and knowledge could also be used to enhance the conservation priorities of these KEFs.

This dataset contains species identifications of molluscs 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 3 May 2010. Species-level identifications were undertaken by Richard Willan at the Northern Territory Museum and were delivered to Geoscience Australia on the 5 May 2010 (leg 1 only). 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.

In early 2014 the RVIB Nathaniel B. Palmer conducted the first ever multidisciplinary study of the Sabrina Coast continental shelf. This area is remote and generally inaccessible, but biological significance is recognised by its initial inclusion within the proposed East Antarctic representative system of Marine Protected Areas. The datasets collected during this voyage allow analysis of the physical habitat parameters and benthic biota through interpretation of bottom camera images, high resolution multibeam bathymetry, sediment properties and oceanographic measurements, with satellite observations of sea ice also providing important environmental context. The suite of environmental and biological datasets provides evidence for a diverse, relatively high biomass continental shelf community that is strongly structured by the physical environment. The distribution of benthic taxa is most closely related ( = 0.592) to seafloor bathymetry, substrate type, latitude and the occurrence of phytodetritus. Phytodetritus accumulation is associated with muddy/sandy substrates, indicating long term sediment focussing in these areas, consistent with evidence of bottom recirculation features. These softer substrates contain relatively high abundances of mobile holothurians and amphipods. Scattered occurrence of dropstones creates habitat heterogeneity at fine-scales. Harder substrates have high abundances of brachiopods, bryozoans, polychaete tubeworms, a range of massive and encrusting sponges and sea whips. Several taxa are found only on areas of hard substrate, yet have a broad distribution across the sites, indicating that the density of dropstones is sufficient for most sessile invertebrates to disperse across the region. The occurrence of dropstones is associated with significant increases in taxa diversity, abundance and percent biological cover, enhancing the overall diversity and biomass of this ecosystem. This study illustrates how multidisciplinary studies can inform understanding of the drivers of benthic ecosystems, providing important constraints for generating realistic ecosystem models and contributing to our understanding of the sensitivity of this community to environmental change.

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.