Creation year

2008

33 record(s)
 
Type of resources
Topics
Keywords
Contact for the resource
Provided by
Years
From 1 - 10 / 33
  • Underwater visual census surveys were conducted at 15 sites in eastern Tasmania to quantify the abundance of the sea urchin Heliocidaris erythrogramma and several putative predators.

  • Behavioural syndromes are important in the context of understanding the evolution of behaviour. This study examines the lifetime development of shy/bold behaviour of dumpling squid (Euprymna tasmanica). The first component examined correlations of shy/bold behaviour across two test contexts - a threat and a feeding test, measured 5 times during the lifetime of the squid. The second component examined developmental plasticity in shy/bold phenotypes with age and sexual maturity.

  • The spatial extent of the long spined sea urchin, Centrostephanus rodgersii, was estimated by divers using underwater visual census methods to survey rocky reef habitats at 13 regions along Tasmania's east coast (between Eddystone Point and Recherche Bay). Within each region 3 subsites were surveyed, and within each subsite 4 belt transects were surveyed. Divers recorded depth, percent substrata type, percent C. rodgersii barrens habitat; abundance of urchins (C. rodgersii and H. erythrogramma), rock lobster (J. edwardsii) and abalone (H. rubra). Divers also recorded algal cover (estimated), C. rodgersii barrens and substratum type using set categories (see below).

  • The Guide to the Marine Zooplankton of south eastern Australia, is an interactive tool providing a comprehensive, fully illustrated means of identification for the major zooplankton located in south eastern Australia. This new identification guide to local marine zooplankton is available online at: http://www.imas.utas.edu.au/zooplankton This is the result of collaboration between the Marine Research Laboratories and School of Zoology, University of Tasmania, and the Australian Antarctic Division. Please note that the full contents of the site will be available on (Free) CD-Rom

  • 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/

  • 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.

  • 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.

  • Sampling of commercial mid-water trawl catches for small pelagics from waters adjacent to Tasmania have yielded an extensive biological dataset in space and time. As a minimum, size composition information is available from most commerical shots undertaken between 2002 and 2006, referenced with operational information (location, depth and catch weight). Subsamples of the key small pelagics, redbait, jack mackerel and blue mackerel, were examined for size, sex, gonad weight and stage and otoliths have been retained for age determination. Further data has been collected since the initial investigation.

  • Interactions between native and introduced species can help to elucidate the impact of exotic species on the broader community. This work examines utilisation of an introduced gastropod, the New Zealand screwshell (Maoricolpus roseus) by native hermit crabs in eastern Tasmania. Samples of screwshells were collected from Bass Strait, Maria Island, Pirates Bay and Dennes Point using a modified scallop dredge or collected by divers. Site location, date, depth, dredge opening size were recorded, and random sub-samples of shells were measured for length and width, and spire damage was scored. Hermit crabs, if present, were identified to species, sexed and measured.

  • This study used crosses of wild-caught dumpling squid (Euprymna tasmanica) males to multiple females with known behavioural types to evaluate patterns of additive and residual variance in behavioural traits from offspring under two contexts - a threat and a foraging test. Genetic contributions to behavioural expression were context-dependent. Threat context behaviour had significant heritability, while foraging context behaviour had lesser additive and greater residual components. Female trait variation was not correlated with fecundity. Female foraging boldness (which co-varied with size) explained some variation in brood hatching success. Positive assortion of mate pairs according to shy-bold phenotype determined fertilization success.