Summary: | Progress Code: completed Statement: Only 17 RMT hauls were able to be made due to severe conditions. The main sampling system used was a rectangular midwater trawl (RMT 8) of 8 square meter mouth area, and 4.5 mm mesh. Initially 0-200 meter downward hauls were made, followed by 0-150m hauls. On runs between stations more than 30 nautical miles apart, a continuous underway (Hardy) plankton recorder (CPR) was used, 300 micro-meter mesh internally. Between Heard Island and Kerguelen, and after Kerguelen the CPR was deployed for normal run times of about 500 nautical miles. 17 RMT 8 shots were made, plus 11 short CPR runs of 30-50 nautical miles and 4 long CPR runs of 250-500 nautical miles. Initial examination was made on board, with the majority of the processing being completed at the Australian Antarctic Division. 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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