This voyage provides an opportunity to test and refine optimal techniques to map and assess seabed habitat developed in a previous CMR project (NOO OP2000-SE02). Importantly, this voyage will use the National Facility's high-resolution EM300 swath mapper for its first program of biological and physical habitat mapping. The sampling locations are a number of submarine canyons and their immediately adjacent flanks on the west coast of Tasmania and east of Bass Strait. These are prime targets for our methods development because each canyon area is characterised by a great variety of seabed topography and benthic communities concentrated in a relatively small area (< 300 sq km). This voyage is also an opportunity to apply the data collected to marine resource management planning in the South East Region. Submarine canyons represent a type of habitat unit ("Level 3 biogeomorphic units") having a strong influence on the location of offshore Marine Protected Areas on the continental slope and rise, and many are likely to be biodiversity "hotspots". Several canyons are also the locations of the largest known aggregations of feeding and spawning fishes in the South-East Fishery region, and these support a range of intense, increasing and, in places, conflicting fishing activities. Given the immediate and increasing relevance of submarine canyons to conservation and fishery managers, it is then surprising to realize that virtually all those in the SE region remain unsampled by scientists, and are named only by commercial fishers. For these reasons, sampling on this voyage will focus on the "Big Horseshoe Canyon" mapped previously with the EM1002 and EM12 swath instruments (to enable comparison of data types, and to investigate temporal persistence of features), and several "new" areas. Sediment samples were taken for analysis by Geoscience Australia.

The scientific objectives for the survey were split across two voyages (SS07/2005 for leg 1 and SS10/2005 for leg 2). The first leg was to map and visually survey (video) the upper continental slope (and at selected sites transects from the outer shelf to the mid-slope) at regular intervals of 1 deg latitude; the second leg was to targeted sample the surveyed locations to document the benthic biodiversity. Sediment samples were divided into two samples: an elutrition sample for macroinvertebrates that was sent to Robin Wilson at MV for analysis and a sediment sample to be analysed by Geoscience Australia.

The overall aims were to provide data on the distribution of deep seabed habitats and fauna that are amenable to scientific hypothesis testing, can be immediately applied to marine resource management processes, and that enable strategic development of tools and techniques for understanding the processes that maintain deep sea biodiversity. This work was to support the process of NWR Estate inventory and management performance assessment by providing interpreted benthic habitat maps, faunal inventories, distribution maps and conservation values. Data will be collected at scientific reference sites from potential MPA areas that can be re-visited for monitoring purposes in the future. Sampling along environmental gradients (geographic range and depth) in this section of Australia's coast will also provide the opportunity to evaluate biogeographic hypotheses. Further refinement of predictive methods for identifying seabed habitat types, initially developed in temperate and cool-temperate environments, will be enabled by data collection from this tropical location in Australia. We intended to highlight the importance of this underlying science as a modern "Voyage of Discovery" given the likely significance of the findings in terms of Australia's biodiversity and its biogeography and evolution. (From Voyage Plan). Sediment samples were divided into two samples: an elutrition sample for macroinvertebrates that was sent to Robin Wilson at MV for analysis and a sediment sample to be analysed by Geoscience Australia.