Zooplankton were collected with a Rectangular Midwater Trawl (RMT 8+1 net) from 37 sampling sites on and near the Southern Kerguelen Plateau. Specimens of the euphausiid Thysanoessa macrura were selected for cohort analysis, based on lengths, and allometry (dry weights and lengths). Lipids were extracted from the animals to provide a lipid content (%) as a function of dry weight. A small number of individuals was examined further to produce profiles of the main fatty acids and fatty alcohols. Instantaneous growth rate experiments (IGR) were conducted onboard to determine growth rates of males, females and juveniles.

Zooplankton were collected with a Rectangular Midwater Trawl (RMT 8+1 net) from 37 sampling sites on and near the Southern Kerguelen Plateau. The contents of each net were preserved in 5% buffered formaldehyde. This dataset covers the counts of the contents of the RMT8 net and includes the abundances for the euphausiid Thysanoessa macrura and the salp Salpa thompsoni. The contents were identified and counted under a Leica M165C stereo-microscope. A flow meter attached to the mouth of the RMT 8 was used to record the volume of seawater passing through the net. The count for Thysanoessa macrura includes the total of all developmental stages. For the salps abundances are shown for the 2 developmental phases - solitary individuals and aggregates.

Metadata record for data expected ASAC Project 11 See the link below for public details on this project. From the abstract of the referenced paper: The Australian Antarctic Division carried out an extensive sampling program for pelagic and benthic fauna in Prydz Bay, Antarctica (Indian Ocean sector) in January to March 1991. A total of 341 cephalopod specimens comprising 256 squids and 85 octopods were captured for study. This preliminary report presents capture records of eight species of squids: Brachioteuthis sp., Kondakovia longimena, Bathyteuthis abyssicola, Mastigoteuthis psychophila, Psychroteuthis glacialis, Alluroteuthis antarcticus, Mesonychoteuthis hamiltoni and Galiteuthis glacialis. The Octopods captured are Megalehedone senei and several species of Pareledone. Psychoteuthis glacialis is reported to congregate on the bottom near the shelf edge at the depth of 400-600 metres. No distinctive pattern in diel vertical movement was found for any of the species captured. Evidence suggests the existence of ontogenetic descent in Galiteuthis glacialis. Cephalopod catches from the extensive sampling program for fishes and zooplankton were studied. For the pelagic fauna, half-hour duration IYGPT hauls were taken at three depths at 63 stations evenly distributed over Prydz Bay area. The three depths fished by the IYGPT at each station were near the surface, near the bottom or 800 m whichever was less, and the midpoint between those two depths. The 63 stations coincided with most of the stations used in the zooplankton sampling program which employed an RMT 1 + 8 net and sampled from 0-200 metres. Additionally 21 benthic samples were taken using bottom trawl, fished for half hour duration on the shelf of Prydz Bay.

The CTD data were acquired when the RMT instrument was in the water. Data Acquisition: There is a FSI CTD sensor housed in a fibreglass box that is attached to the top bar of the RMT. The RMT software running in the aft control room establishes a Telnet connection to the aft control terminal server which connects to the CTD sensor using various hardware connections. Included are the calibration data for the CTD sensor that were used for the duration of the voyage. The RMT software receives packet of CTD data and every second the most recent CTD data are written out to a data file. Additional information about the motor is also logged with the CTD data. Data are only written to the data file when the net is in the water. The net in and out of water status is determined by the conductivity value. The net is deemed to be in the water when the conductivity averaged over a 10 second period is greater than 0. When the average value is less than 0 the net is deemed to be out of the water. New data files were automatically created for each trawl. Data Processing: 1. Adjustment of the net open time. If the net did not open when first attempted then the net was 'jerked' open. This meant the winch operator adjusted the winch control so that it was at maximum speed and then turned it on for a very short time. This had the effect of dropping the net a short distance very quickly. This dislodges the net hook from its cradle and the net opens. The scientist responsible for the trawl would have noted the time in the trawl log book that the winch operator turned on the winch to jerk the net. The data files will have started the 'net open' counter 10 seconds after the user clicks the 'Net Open' button. If this time did not match the time written in the trawl log book by the scientist, then the net open time in the CSV file was adjusted. The value in the 'Net Open Time' column will increment from the time the net started to open to the time that the net started to close. The pressure was also plotted to ensure that the time written down in the log book was correct. When the net opens there is a visible change in the CTD pressure value received. The net 'flies' up as the drag in the water increases as the net opens. If the time noted was incorrect then the scientist responsible for the log book, So Kawaguchi, was notifed of the problem and the data file was not adjusted. 2. Removing unused columns from the original log files. The original log files that were produced by the RMT software were trimmed to remove any columns that did not pertain to the CTD data. These columns include the motor information and the ITI data. The ITI data gives information about the distance from the net to the ship but was not working for the duration of the BROKE-West voyage. This trimming was completed using a purpose built java application. This java class is part of the NOODLES source code. Dataset Format: The dataset is in a zip format. There is a .CSV file for each trawl, 125 in total. There were 51 Routine trawls and 74 Target Trawls. The file naming convention is as follows: [Routine/Target]NNN-rmt-2006-MM-DD.csv Where, NNN is the trawl number from 001 to 124. MM is the month, 01 or 02 DD is the day of the month. Also included in the zip file are the calibration files for each of the CTD sensors and the current documentation on the RMT software. Each CSV file contains the following columns: Date (UTC) Time (UTC) Ship Latitude (decimal degrees) Ship Longitude (decimal degrees) Conductivity (mS/cm) Temperature (Deg C) Pressure (DBar) Salinity (PSU) Sound Velocity (m/s) Fluorometer (ug/L chlA) Net Open Time (mm:ss) If the net is not open this value will be 0, else the number of minutes and seconds since the net opened will be displayed. When the user clicks the 'Net Open' button there is a delay of 10 seconds before the net starts to open. The value displayed in the 'Net Open Time' column starts incrementing once this 10 seconds delay has passed. Similarly when the user clicks the 'Net Close' button there is a delay of 6 seconds before the net starts to close. Thus the counter stops once this 6 seconds has passed. Acronyms Used: CTD: Conductivity, Temperature, Pressure RMT: Rectangular Midwater Trawl CSV: Comma seperated value FSI: Falmouth Scientific Inc ITI: Intelligent Trawl Interface This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679).

Regular Trawl At each regular trawl station a quantitative standard double oblique tow was conducted from the surface down to 200 m (or to within 10 m of the bottom at stations shallower than 200 m). Such a depth range is considered to be the best compromise between the time available for sampling and the likely vertical depth range of krill. During the hauls, ship speed was maintained at a constant 2.5 plus or minus 0.5 knots. Wire speed of 0.7 to 0.8 m/s during paying out and of 0.3 m/sec during hauling (approx. 0.5 m/s and 0.2 m/s respectively at vertical depth change rate). The net mouth angle is remarkably constant during hauling within the speed ranges given above. When the net reaches maximum depth, the winch was stopped for about 30 seconds to allow the net to stabilise before starting retrieval. When hauling, propeller thrust was turned off when the net reached a depth of 15 to 20 m; this was to minimise the effects of the propeller action on the net operation and avoids damage of the samples. Target Trawl Whenever interesting targets were seen on the echo-sounder, or large amounts of krill were required for any purpose, target trawls were performed. Once the position of the target was marked, the ship was turned and navigated to run over the target from direction required within navigation capacity. The ship speed was lowered down to below 2.0 knots before hitting the target, so that the net could be lowered down to the desired depth whenever the net reached the target. Fine adjustments were made throughout the trawl by monitoring the echo-sounder in the aft control room. For live krill target trawl, ship speed was kept as slow as possible to avoid any damage to krill. Sample processing for all regular trawl stations: RMT-8 1.Measure the total sample volume (Drain water, then measure using water replacement; mandatory only for the regular hauls) 2.Sort out all Antarctic krill and count their number. If the sample mainly consists of krill and the volume is more than ~1L, a known portion of the whole sample was sub-sampled for the further processing. 3.Stage (TL, Carapace Length, Maturity) of all krill (or subsample), up to 50 to 150 individuals, and digestive gland size (the longest axis) of up to 50 individuals were measured using digital calipers. 4.Other zooplankton groups were immediately sorted out from the catch and their numbers were recorded. Preservation of RMT-8 samples Krill (including those used for onboard demography measurements) were fixed in 10% formalin for their further analysis. Whenever excess amount of krill catch were made, they were sampled and frozen for POP (persistent organic pollutant) measurements, preserved in 80% ethanol for genetic analysis, and frozen under -80C/ liquid nitrogen for chemical analysis. Fish were preserved in formalin, EtOH, or frozen. Squids were preserved in ethanol. RMT-1 1.The whole sample was fixed with 10 % formalin. 2.If the sample volume was too large, then a known proportion of catch was randomly sub-sampled and fixed. This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679).

This dataset contains results from the Second International BIOMASS Experiment II (SIBEX II) cruise of the Nella Dan, January 1985. This cruise is the fourth cruise out of a series of six, investigating the distribution, abundance and population structure of krill Euphausia superba in the Prydz Bay region, Antarctica. SIBEX II was co-ordinated with South Africa, Japan and France, and 66 grid sampling stations covered an area from 58 degrees to 93 degrees East and from 60 degrees South to the Antarctic coast. At each sampling station, surveys of krill and other zooplankton were taken, as well as a CTD cast and water collection for phytoplankton pigment, nutrients and primary production measurement. Species identity and abundance data were obtained. The major species investigated were Euphausia superba, Euphausia frigidia, Euphausia crystallorophias and Thysanoessa marcuria. Other pteropods and cephalopods were also studied, as well as results from hydroacoustic surveys of krill biomass. Summary results are listed in the documentation. The fields in this dataset are: species Station Number Haul Type RMT Biomass Weight Flowmeter Latitude Longitude Time Date Ice Sea State Density Sea Floor Maturity This dataset was updated by Angela McGaffin. This download file also contains the original dataset provided in 2007. There are four files available: SIBEX_II_krill.xls (original file) sibex2_krill_morphometrics.xslx sibex2_station_data.xslx sibex2_zooplankton_corrected.xls A minor data update took place on 202211-03 to add a scanned copy of the original acoustics log.

Metadata record for data from ASAC Project 2388 See the link below for public details on this project. ---- Public Summary from Project ---- The HIMI Ecosystem Project is aimed at examining key predators based on Heard Island, including albatross, penguins and seals, and their interactions with prey, the ocean and benthic environment and commercial fisheries. Work will include examining the diet of the animals, tracking them to determine where they feed, and examining prey available in the feeding areas. Scientists from a variety of backgrounds including bird and mammal biologists, marine biologists, oceanographers and marine geologists will be involved. These data were collected on Aurora Australis voyage 4 2004 ('HIPPIES'). The data are stored in a Microsoft Access 97 file. The data includes sampling information for trawls using an IYGPT (International Young Gadoid Pelagic Trawl) Net and RMT 8 (8 square meter Rectangular Midwater Trawl) Nets. Sampling data, including location and time, are stored in the 'Hauls' table. Data from the analysis of the contents of each trawl, including species identifications, mass and counts of each taxon of mesopelagic fish and zooplankton are stored in the 'Bycatch' table. Weights, lengths and other biological data collected from individual mesopelagic fish are stored in the 'Fish Data' table. On opening the file the Haul form launches automatically giving access to the data. The fields in this dataset are: Latitude Longitude Species Date Haul Number Time Depth (m) Tow distance Wire out Tow Speed (knots) Headline height (m) Headline width (m) Gear Comments Fishing Ground Fishery Traps Line Hooks Magazines Fish length Otoliths Scale sample Fish Weight Stomach Gonads Stomach contents

This dataset contains results from the Antarctic Division BIOMASS Experiment III (ADBEX III) cruise of the Nella Dan. It is the fifth cruise in a series of six, conducting a long term field survey providing data on distribution, abundance and population structure of the krill Euphausia superba in the Prydz Bay region, Antarctica. The prime purpose of ADBEX III was to study the ecology of the Crabeater Seal, and surveys of krill and other zooplankton were taken off Antarctica in the Australian sector (east of Mawson) in the Enderby Land region between October and November 1985. Species identity and abundance data were obtained. The major species investigated were Euphausia superba, Euphausia frigidia, Euphausia crystallorophias and Thysanoessa marcuria. Other pteropods and cephalopods were also studied. A CTD cast and water collection for phytoplankton pigment, nutrients and primary production measurements were also made at each net sampling station. Summary results are listed in the documentation. The fields in this dataset are: species Station Number Haul Type RMT Biomass Weight Flowmeter Latitude Longitude Time Date Ice Sea State Density Sea Floor Dive Maturity A minor data update was made on 2022-11-03 to add scanned copies of acoustic logs from the voyage.