| Summary: | Progress Code: completed Statement: 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. All fish were identified, weighed and measured on board, except specimens too small for weighing accurately, which were frozen and returned to Australia for accurate weighing. For common species guts, gonad, and otoliths were removed for 25 specimens of each species per haul. For large catches of individual species, a random subsample of 50 was individually weighed, measured, and guts gonads and otoliths removed; a further 50 were weighed and measured, and a further 100 were measured. The total number and weight of each species was also recorded. Please see the provided reference for further details. This dataset contains the data from Voyage 6 1990-91 of the Aurora Australis. The observations were taken from the Prydz Bay area, Antarctica in January and February 1991. The data contains the results from pelagic fish trawl surveys. The major species were Pleuragramma antarcticum, Channich thyid, Dacodraco hunteri and Neopagetopsis ionah. This is a subset of the data for the whole voyage. The objectives of the fish program were: to assess the distribution and abundance of pelagic fish in the Prydz Bay area; to re-sample bottom fish at sites on the continental shelf previously sampled with a small beam trawl, but using a large atter trawl to check the validity of the beam trawl's samples; to investigate the biology of the more important ...
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