TRAWL
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This dataset is a document describing the 66 species of Hydromedusae found in the Southern Ocean. It lists all the known species, and with illustrated diagrams provides a guide to their taxonomic identification. It also includes general information about Hydromedusae and collection and preservation. The document is available for download as a pdf from the provided URL.
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This dataset contains the data from Voyage 7.2 1989-90 of the Aurora Australis. The observations were taken from around Heard Island between May and June 1990. The objective of the zooplankton program was to determine the composition, distribution and abundance of zooplankton with the Heard Island-Kerguelen area, thus providing information of food availability to planktivorous fish. Surveys of krill and other zooplankton were made to obtain species identity and abundance data, length and age. Euphausia valentini and Themisto gaudichaudi were found to be the dominant species in the region. Other major species included the euphausiid Thysanoessa, the copepod Rhincalanus gigas and chaetognaths of the genus Sagitta. This dataset is a subset of the full cruise.
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A trawl survey is conducted each year at Heard Island and McDonald Islands (HIMI) to assess the abundance and biology of fish and invertebrate species. The survey provides information for input into the stock assessments for the two main fished species, Patagonian toothfish (Dissostichus eleginoides), and mackerel icefish (Champsocephalus gunnari). In addition, it provides information on biodiversity and bycatch species from the fishery. Nine strata were defined as areas for sampling during the annual Random Stratified Trawl Survey (RSTS) conducted on board an industry vessel. The area of the plateau down to 1000 metres depth was divided into nine strata, each covering an area of similar depth and/or fish abundance. A number of randomly allocated stations (between 10 and 30) are sampled in each stratum during every survey to assess the abundance of juvenile and adult toothfish on the shallow and deep parts of the Heard Island Plateau (300 to 1000 metres depth) and to assess the abundance of mackerel icefish on the Heard Island Plateau. Although the number and boundaries of strata have been adjusted over the years, they have been consistent since 2002 (Welsford et al. 2006). This dataset consists of a polygon shapefile representing the strata and a map displaying the strata.
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A series of 6 sets of midwater trawls in Prydz Bay. Each trawl set took place over a 24 hour period to test the extent of diurnal vertical migration in P. antarcticum. Part of the KROCK cruise of Aurora Australis. These data have been incorporated into an 'historical fish database' available for download at the URL given below (Access Database). These data have also been included in the Australian Antarctic Data Centre's Biodiversity database, and have been submitted to GBIF and OBIS (Global Biodiversity Information Facility, and Ocean Biogeographic Information System). The fields in this dataset are: Species Cruise Start Date End Date Sampling Date Vessel Name Fishing Area Latitude Longitude Gear Length Weight Sex Gonad Weight Stomach Weight
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This dataset is a document describing the Ctenophores of the Southern Ocean. It lists all the known species and with illustrated diagrams provides a guide to their taxonomic identification. The document is available for download as a pdf from the provided URL.
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This dataset is a document describing the Pelagic Polychaetes of the Southern Ocean. It lists all the known species and with illustrated diagrams provides a guide to their taxonomic identification. The document is available for download as a pdf from the provided URL.
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This dataset contains results from the Aurora Australis Voyage 6 1990-91. Surveys of krill and other zooplankton were taken in Prydz Bay, Antarctica between January and February 1991. Species identity and abundance data, length, age, growth rate and mortality rate data were obtained. The major species investigated were Euphausia superba, Euphausia frigidia, Euphausia crystallorophias and Thysanoessa macrura. Other pteropods and cephalopods were also studied. This dataset is a subset of the full cruise.
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This dataset contains scanned copies of the RMT and bottom trawl logs from Voyage 6 1990-91 (AAMBER2) of the Aurora Australis. This was primarily a marine science voyage. Surveys of krill, other zooplankton and pelagic fish were taken in Prydz Bay, Antarctica between January and February 1991. 177 midwater trawls were successfully completed at 59 stations. Midwater fish were sampled using an International Young Gadoid Pelagic Trawl (IYGPT). At each station, hauls were taken at depths of 20-30m, approximately halfway down the water column, and 20-30m above the bottom. At six stations, the lowest sample was duplicated using a light fitted to the net. Where samples were made off the shelf, standard depths of 20-30m, 400m, and 800m were fished. All hauls were of 30 minutes fishing time. Bottom trawls were made using a 35m headline length otter trawl fitted with 40cm diameter bobbin gear. A 2" mesh cod end liner was used to retain small fish. On both nets, a Simrad trawl surveillance sonar was used.
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This database provides the most comprehensive systematic list of mega-epibenthic assemblages in the Australian Economic Exclusive Zone (AEEZ) of Heard Island and McDonalds Islands (HIMI) at water depths between 168 and 970 m. Data were collected to better understand the types and distribution of benthic invertebrates, their vulnerability to bottom fishing, and the effectiveness of the HIMI Marine Protected Area (MPA) for representing and protecting the regions benthic biodiversity. A total 504 taxa from 14 phyla were collected from 129 stations throughout HIMI. Two methods, beam trawl (for non-complex flat terrains) and epibenthic sled (for more complex, rough terrains), were used to sample the megabenthos. Both the trawl and sled were fitted with a 1 cm-2 mesh cod-end with a net opening (height x width) of 2.7 x 1.2 m for the beam trawl and 1.2 x 0.6 m for the epibenthic sled. Samples were sorted into broad taxonomic groups onboard the sampling vessel then frozen for later analysis. In the laboratory, samples were sieved over a 1 cm mesh and all dead material removed. Megabenthos were identified to the lowest possible taxonomic level by using the available literature and assistance of taxonomic specialists. All non-colonial taxa were counted and then weighed. Colonial taxa that could not be counted as individuals, e.g. demosponges and bryozoans, were separated to the lowest taxonomic level and a whole weight recorded per sample. Taxonomic expertise was provided by Dick Williams (Osteichthyes and Chondrichthyes) of the Australian Antarctic Division; Daphne Fautin and Andrea Crowther (Actinaria) of the University of Kansas; Cardin Wallace (Actinaria) from Queensland Museum; Elizabeth Turner (Bivalvia and Gastropoda) and Genefor Walker-Smith (Invertebrates) from the Tasmanian Museum and Art Gallery; Phillip Bock (Bryozoa), Mark Norman (Cephalopoda), Gary Poore (Crustacea), Joanne Taylor (Decapoda), Mark O'Loughlin (Holothuriodea), Jan Watson (Hydrozoa), Tim O'Hara (Ophiuroidea and Asteroidae), Robin Wilson (Polychaeta) and David Staples (Pycnogonida) of Museum Victoria; Igor Smirnov (Ophuroidea) of the University of Russia; and Andrew Hosie (Cirripedia) of the Western Australian Museum. A reference collection of the taxa is lodged at the Tasmanian Museum and Art Gallery, Hobart, Tasmania. On 2022-11-02 a minor data update was made to add scanned copies of old worksheets.
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This dataset is a document describing the Chaetognaths of the Southern Ocean. The synonymy, diagnostic characters, geographical and bathymetric distribution of each species is given together with an illustration of body, head and a seminal vesicle, and a distribution map. The document is available for download as a pdf from the provided URL.