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  • The aim of this study is to use artificial boulders in the form of sandstone blocks to investigate the benthic cryptofaunal communities of subtidal rocky reefs; specifically to quantify temporal and spatial patterns, the influence of the sub-block reef profile, and protection from fishing on these animals at locations inside and external to the Maria Island marine reserve in eastern Tasmania.

  • This study assessed the spatial and temporal (horizontal and vertical) distribution of Asterias amurensis larvae in the Derwent Estuary and adjacent Storm Bay, SE Tasmania. Horizontal transport and development was assessed by collecting plankton samples at 2 or 4 week intervals, from July to December 2001, at 4 sites in the Derwent Estuary and 6 sites in Storm Bay. The effects of light and salinity on vertical distribution of larvae was examined over a 24 hour tidal and diel cycle.

  • Reef Life Survey is a program that trains and assists a network of skilled and committed recreational divers to cost-effectively assess the state of the inshore marine environment at the continental scale. The program uses standardised underwater visual census methods employed by SCUBA divers to survey fish and invertebrate species and to record macroalgal and coral cover using photo quadrats - this record refers to the website for this program. By standardising techniques and establishing a monitoring system on a nation-wide scale, the program addresses many of the current problems associated with managing the marine environment, including the paucity, patchiness and variable quality of data on the distribution of and trends to marine biodiversity. A central database is managed for the storage, analysis and dissemination of data collected nationally, with a publicly-accessible web-based portal. The website allows information collected on Australia's marine environment to be accessed in a meaningful form by policy-makers and the general public, including recreational groups, scientists and industry. It also has information and resources for particpating divers and those wishing to become involved. The dataset generated by recreational divers will provide a national framework for monitoring the state of the inshore environment and the identification of those threats and locations of greatest conservation concern. This record points to the online resource for Reef Life Survey: http://www.reeflifesurvey.com/

  • The data is quantitative abundance of fish and megafaunal invertebrates and algal % cover derived from transect based counts at a wide range of locations across Temperate Australia. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. Methods were initially developed for research on temporal changes following protection in Tasmanian MPAs (Maria Is, Tinderbox, Ninepin Point, Governor Island). Further research has collected data in Tasmania, in MPA planning surveys (e.g. St Helens, Waterhouse Region, Low Head, Lillico Beach, Rocky Cape), an oil spill assessment (Low Head), and in studies and surveys in new Tasmania MPAs (Port Davey and the Kent Group). The data represented by this record was collected in MPA planning surveys and for opportunistic surveys such as the Low Head oil spill assessment. In many cases the dataset involved temporal replication (year scale).

  • Timed GPS-tracked swims using SCUBA (45 and 30 minutes), were used to assess the changes in frequency and size of Centrostephanus rodgerii incipient barrens in eastern Tasmania. The number of C. rodgerii and Heliocidaris erythrogramma in each incipient barren were also assessed.

  • A photographic and in situ diver survey of marked incipient Centrostephanus rodgersii barren patches, in eastern Tasmanian, was used to assess any changes in the grazed area and shape at experimental (lobster translocation/ research reserve protection sites; and abalone diver urchin cull sites) versus control sites.

  • 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.

  • In the Derwent Estuary (south eastern Tasmania, Australia), the introduced northern Pacific seastar Asterias amurensis is highly abundant and fecund when associated with anthropogenic structures (wharves and marinas). Based on modelled predictions of fertilisation success, seastars at wharf 'hotspots', whilst representing <10% of the total population in the Derwent Estuary, and concentrated in <0.1% of the total area, contribute up to >80% of total larval production in the estuary. Reproductive potential of populations at wharf and control sites was quantified (in terms of individual capacity and spatial characteristics of the population. A large scale survey was undertaken in the Derwent estuary (to 27m) to determine spatial distribution of the species. Zygote production (i.e. number of fertilised eggs) was used as a measure of reproductive output and was simulated using empirical estimates of spatial and reproductive parameters of the adult seastars in a spatially explicit model of fertilization (developed by A. Morris and C. Johnson).

  • Linear video transects (40m total length; 20m into barrens and 20m into kelp from original fixed marker on the benthos) were used to assess changes in kelp growth in several points along the kelp - urchin barren interface in north-east Tasmania (St. Helens Island, Sloop Rock and Elephant Rock research areas). The video transects were deployed in the same position, and assessed at different points of time. The video was analysed in the laboratory to assess percentage of kelp and barren cover, as well as the kind of substratum, kelp species identifiable and number of sea urchins (Centrostephanus rodgerii and Heliocidaris erythrogramma) and other benthic organisms when present (rock lobster and abalone).

  • Quantitative surveys were undertaken at five sites in the Kent Group, north eastern Tasmania (Murray Pass, Winter Cove, Little Squally Cove,and southern end of Erith Island) by divers using underwater visual census methods to survey the reef habitat. Additional spot dive surveys were undertaken at northern side of East Cove, Garden Cove, Winter Cove, Squally Cove (Deal Island), northern and southern sides of West Cove (Erith Island) and north east and north west coasts of Dover Island. Divers recorded numbers of sea urchins (Centrostephanus rodgersii and Heliocidaris erythrogramma), as well as extent of urchin barrens, size of algal patches, and measured boundaries of macroalgal patches of Macrocystis angustifolia, Phyllospora comosa and Ecklonia radiata-fucoid communities. Spot dives detailed additional qualitative observations of C. rodgersii.