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biota

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  • Characterisation of lobster (Jasus edwardsii) abundance and change in abundance at three different sampling sites (Cape Paul Lemanon, North Bay and Fortescue Bay) on the south-east coast of Tasmania, was assessed by GPS tracked SCUBA diver swims of 60 minutes in length whereby GPS was logged approximately every 5 seconds. Large tagged Rock Lobsters were introduced into one of the sampling sites, North Bay (which was closed to fishing). The swims are also being used to assess the impact of reef closure on the local lobster population.

  • The data is a collection of reef habitat structure measurements from sites around Tasmania with regional snapshots from Jurien Bay (WA) and Jervis Bay (NSW). Explanatory variables investigated were depth, duration of protection from fishing within marine protected area, rugosity, boulder substratum at a site, the average number of refuge size categories, and a fractal refuge index that reflected the frequency distribution of different sized physical refuges. Also considered were biogenic habitat structure in the form of the percent cover of canopy algae and the biomass of predatory fish.

  • Mesozooplankton community composition and structure were examined throughout the D’Entrecasteaux Channel, Huon Estuary and North West Bay, Tasmania, from November 2004 to October 2005, the data represented by this record was collected on the 06/09/2005. The composition of the mesozooplankton community was typical of inshore, temperate marine habitats, with seasonally higher abundance in summer and autumn and lower numbers in winter and spring. Copepods were the largest contributors to total abundance across all seasons and stations, while cladocerans and appendicularians were proportionally abundant in spring and summer. The faecal pellets of these three main groups, along with those of krill and amphipods, also contributed significantly to material recovered from sediment traps. Meroplanktonic larvae of benthic animals showed short-term peaks in abundance and were often absent from the water column for long periods. Spatially, North West Bay and the Channel had a higher representation of typically marine species, including Calanus australis and Labidocera cervi, while truly estuarine species, such as the copepod Gladioferens pectinatus, were more important in the Huon Estuary.

  • We investigated the effects of seabird presence and seasonality on ground-active spider community structure (activity-density, family-level richness, age class and sex structure) and composition at the family-level across five short-tailed shearwater breeding islands around south-eastern Tasmania, Australia. Using 75 pitfall traps (15 per island), spiders were collected inside, near and outside seabird colonies on each island, at five different stages of the short-tailed shearwater breeding cycle over a year. 3. Pitfall traps were deployed for a total of 2,674 days, capturing 1,592 spiders from 26 families with Linyphiidae and Lycosidae the most common.

  • The predators of Centrostephanus rodgersii, were identified using remote video monitoring. Experiments were performed in two eastern Tasmanian regions, the Maria Island Marine Reserve (MIMR, 42° 35.26'S, 148° 3.03'E) and the Crayfish Point Research Reserve (CPRR, 42° 57.37'S, 147° 21.30'E). The impact of fishing on these predators, and ultimately on C. rodgersii, was examined by comparing survival of C. rodgersii on reefs inside no-take Marine Protected Areas (MPAs) (high predator biomass) relative to fished reefs (low predator biomass). The size-specific nature of predation interactions was examined in context of size-selective fishing pressures within the sea urchin's extended range.

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    Opportunistic visual surveys were conducted in transit to, and within, the Oceanic Shoals Commonwealth Marine Reserve (CMR) in the Timor Sea during September and October 2012 onboard the RV Solander. This resource comprises species lists and estimated counts of marine mammals, sea snakes, seabirds, sea turtles and other large wildlife encountered during the voyage. The Oceanic Shoals Commonwealth Marine Reserve survey was undertaken as an activity within the Australian Government's National Environmental Research Program Marine Biodiversity Hub and was the key component of Research Theme 4 - Regional Biodiversity Discovery to Support Marine Bioregional Plans. Hub partners involved in the survey included the Australian Institute of Marine Science, Geoscience Australia, the University of Western Australia, Museum Victoria and the Museum and Art Gallery of the Northern Territory. Data acquired during the survey included: multibeam sonar bathymetry and acoustic backscatter; sub-bottom acoustic profiles; physical samples of seabed sediments, infauna and epibenthic biota; towed underwater video and still camera observations of seabed habitats; baited video observations of demersal and pelagic fish, and; oceanographic measurements of the water column from CTD (conductivity, temperature, depth) casts and from deployment of sea surface drifters. Further information on the survey is available in the post-survey report published as Geoscience Australia Record 2013/38: Nichol, S.L., Howard, F.J.F., Kool, J., Stowar, M., Bouchet, P., Radke, L.,Siwabessy, J., Przeslawski, R., Picard, K., Alvarez de Glasby, B., Colquhoun, J., Letessier, T. & Heyward, A. 2013. Oceanic Shoals Commonwealth Marine Reserve (Timor Sea) Biodiversity Survey: GA0339/SOL5650 - Post Survey Report. Record 2013/38. Geoscience Australia: Canberra. (GEOCAT #76658).

  • Mesozooplankton community composition and structure were examined throughout the D’Entrecasteaux Channel, Huon Estuary and North West Bay, Tasmania, from November 2004 to October 2005, the data represented by this record was collected on the 07/12/2004 The composition of the mesozooplankton community was typical of inshore, temperate marine habitats, with seasonally higher abundance in summer and autumn and lower numbers in winter and spring. Copepods were the largest contributors to total abundance across all seasons and stations, while cladocerans and appendicularians were proportionally abundant in spring and summer. The faecal pellets of these three main groups, along with those of krill and amphipods, also contributed significantly to material recovered from sediment traps. Meroplanktonic larvae of benthic animals showed short-term peaks in abundance and were often absent from the water column for long periods. Spatially, North West Bay and the Channel had a higher representation of typically marine species, including Calanus australis and Labidocera cervi, while truly estuarine species, such as the copepod Gladioferens pectinatus, were more important in the Huon Estuary.

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    A supervised classification was applied to a Landsat TM5 image. This image was acquired 9:40 am, on the 27th July 2011 (5.14 am low tide at Brisbane Bar). The image classification was applied on areas of clear waters up to three metres depth and for exposed regions of Moreton Bay. Field validation data was collected at 4797 survey sites by UQ. GPS referenced field data were used as training areas for the image classification process. For this training the substrate DN signatures were extracted from the Landsat 5 TM image for field survey locations of known substrate cover, enabling a characteristic "spectral reflectance signature" to be defined for each target. The Landsat TM image, containing only those pixels in water < 3.0m deep, was then subject to minimum distance to means algorithm to group pixels with similar DN signatures (assumed to correspond to the different substrata). This process enabled each pixel to be assigned a label of either seagrass cover (0, 1-25 %, 25-50 %, 50-75 % and 75-100 %). The resulting raster data was then converted into a vector polygon file. Species information was added based on the field data and expert knowledge. Both polygon files were joined by overlaying features of remote sensing files with the EHMP field data to produce an output theme that contains the attributes and full extent of both themes. If polygons of remote sensing were within polygons of field data the assumption was made that the remote sensing polygon was showing more detail and the underlying field polygon was deleted.

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    In giant crabs (Pseudocarcinus gigas), two sets of data were collected: the first examined changes in egg composition during embryogenesis and the second assessed effects of female size on egg composition.

  • A survey was conducted for Macrocystis pyrifera (Linnaeus) C. Agardh 1820 from Eddystone Point to South East Cape The survey was conducted from light aeroplane. Areas of Macrocystis pyrifera beds were marked on 1:100,000 topographical land tenure maps using landmarks as references. A Trimble GPS unit was used to track position in the aeroplane. As boundaries of the beds were flown over, these were marked on the GPS. When plotted up, these information assisted in determining Macrocystis bed boundaries where these were not close to the coast.