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  • Raw and processed acoustic data were collected in East Antarctica from the RSV Aurora Australis during two surveys: the Krill Availability, Community Trophodynamics and AMISOR Surveys (KACTAS) and the Krill Acoustics and Oceanography Survey (KAOS) in the East Antarctic. Seabed alias example file used to make Figure 3. 38_false_bottom.sv.csv (file size: 10.7 MB) This file is an example of seabed aliasing (false bottom echo) that occurred during the KAOS survey. The data in this file are acoustic (mean volume backscattering strength, Sv) sample-by-sample and in a CSV format. Ping_index - ping number Distance_GPS - along track distance from the vessel’s GPS (nautical miles). Distance_vl - along track distance from the vessel’s log (nautical miles). Not used here, so is populated by Echoview’s ‘don’t care’ value (-9.90E+37) to keep the file format consistent. Ping_date - format yyyy-mm-dd Ping_time - format hh:mm:ss Ping_milliseconds - format (integer; ms) Latitude - position from the vessel’s GPS (degrees) Longitude position from the vessel’s GPS (degrees) Depth_start - start depth of vessel echosounder logging range (m) Depth_stop - stop depth of vessel echosounder logging range (m) Range_start - start range of vessel echosounder logging range (m) Range_stop - stop range of vessel echosounder logging range (m) Sample_count number of samples in a ping. Acoustic Sv samples follow in column-wise vector (dB re 1 m-1) Transect metadata all_transects.csv (file size: 14.8 K) This is the transect metadata for both the KACTAS and KAOS surveys: Transect - transect number startDate - start date of transect dd/mm/yyyy startTime - start time of transect hh:mm endDate - end date of transect dd/mm/yyyy endTime - end time of transect dd/mm/yyyy Ping_subset - a ping subset specified between two timestamps to isolate acoustic data that occurred on transect , i.e start timestamp to stop timestamp (yyyy-mm-dd hh:mm = yyyy-mm-dd hh:mm). Direction - Direction traveled along the transect (N - north or S- south). Light - day or night when transect was observed Survey - Either KACTAS or KAOS Leg - Krill box 1 or 2 (there were two surveys only during the KAOS voyage). Pass - Sampling bout for a transect in a given direction. Example R-code FigureAndDataprocessingExample.R (12KB) This R-code provides examples of scripting acoustic data processing using EchoviewR, specifically, using ping-subsets to isolate acoustic data along a transect of interest, detecting schools and exporting echo integrations for 38, 120 and 200 kHz. The R-code for making the figures in the paper is also given. GPS vessel positions for both the KACTAS and KAOS surveys KACTASandKAOS_GPS.csv (3 MB) This CSV file gives the vessel track for both the KACTAS and KAOS surveys. GPS_date - dd/mm/yyyy GPS_time - HH:MM:SS GPS_milliseconds - integer Latitude - position from the vessel’s GPS (degrees) Longitude - position from the vessel’s GPS (degrees) x - relative grid position (x) used for plotting Figure 1 y - relative grid position (y) used for plotting Figure 1 Survey - either: KACTAS_Krillbox, KAOS_Krillbox1, or KACTAS_Krillbox2 Krill swarms for both the KACTAS and KAOS surveys KACTASandKAOSswarms.csv (2.1 MB) Krill swarms descriptors for the KACTAS and KAOS surveys in CSV format (see Table 2 for description of the data fields). Echoview file for the KACTAS survey KACTAS-survey.EV (21.8 MB) An Echoview file (version 12.0) for the KACTAS acoustic data analysis KACTAS EK60 scientific echosounder calibration values KACTAS_EK500_calibration.ecs 3,623 16/05/2022 21:21 -a-- An Echoview format calibration file for the KACTAS survey (see Table 3 for calibration values and Demer et al.20 for a description of the calibration parameters). Echoview file for the KAOS survey KAOS-survey.EV (16.4MB) An Echoview file (version 12.0) for the KAOS acoustic data analysis KAOS EK60 scientific echosounder calibration values KAOS_EK60_calibration.ecs 5,711 01/11/2021 04:36 -a– An Echoview format calibration file for the KAOS survey (see Table 3 for calibration values and Demer et al. (2015) for a description of the calibration parameters).

  • This dataset contains data on the habitats, distribution and numbers of Adelie Penguins (Pygoscellis adeliae) along the Vestfold Hills coast (including colonies on the mainland and offshore islands) during November 1973. The data are obtained from counts at the colonies and black and white photographs. Some aerial photographs were taken at Davis in 1981-82 and 1987-88, and will be compared to the results of this survey. The results are listed in the documentation. A total of 174178 26127 breeding pairs were counted. An increase in Adelie penguin population was found at most locations in East Antarctica. Data from this record has been incorporated into a larger Adelie penguin dataset described by the metadata record - Annual population counts at selected Adelie Penguin colonies within the AAT (SOE_seabird_candidate_sp_AP). It also falls under ASAC project 1219 (ASAC_1219).

  • Metadata record for data from ASAC Project 1306 See the link below for public details on this project. ---- Public Summary from Project ---- The locations and characteristics of nest sites in the Larsemann Hills of three lesser-known seabird species will be mapped. Rapid survey techniques will be trialled and the diets and chronology of breeding determined. The influence of human activities on Broknes on skuas and other seabirds will be examined. Location of seabird colonies recorded using a Garmin 12XL GPS unit (averaged). Nest reference numbers refer to ANARE Research Notes 35, Breeding distribution and abundance of surface-nesting petrels in the Rauer Islands, East Antarctica by K. Green and G.W.Johnstone. The download file contains a number of photographs and a word document providing further information. Also see the metadata records: "Windmill Islands 1:10000 Some abandoned penguin rookery sites point GIS Dataset" and "Windmill Islands 1:10000 Some abandoned penguin rookery sites polygon GIS Dataset".

  • This dataset contains data on the habitats, distribution and numbers of Adelie Penguins (Pygoscellis adeliae) in the Mawson area, Antarctica during 1981 and 1988. The data are obtained from aerial photographs obtained at various times, during the 1981-82 and 1988-89 seasons. The results are listed in the documentation. Comparisons are made with census data collected in the 1971-72 summer. Data from this record has been incorporated into a larger Adelie penguin dataset described by the metadata record - Annual population counts at selected Adelie Penguin colonies within the AAT (SOE_seabird_candidate_sp_AP). It also falls under ASAC project 1219 (ASAC_1219).

  • Data Acquisition: DIFAR (DIrectional Fixing And Ranging) 53D sonobuoys were deployed every 30 minutes of longitude during each of the north-south sampling transects as part of the acoustic survey for marine mammals. Sonobuoys were also deployed opportunistically when large numbers of whales (in particular minke whales) were sighted. Additionally, on the initial E-W transect (#12) sonobouys were deployed prior to the majority of CTD stations. The VHF receiving system for the sonobuoys aboard the ship began with a 6 element YAGI antenna mounted atop the ship's mast. The sonobuoy's VHF signal output from the YAGI was amplified through an Advanced Receiver Research VHF amplifier and received on ICOM PCR-1000 VHF receivers modified to improve low frequency audio output. The audio signal passed through a low pass anti-alias filter (National Instruments analogue bessel SCXI module) and was recorded onto a laptop through a National Instruments E-series (model 6062E) sound card at a sampling rate of 48kHz. Difar sonobuoys have an effective audio response up to 2.5kHz before the low-pass filter roll-off starts. DIFAR bearing information is carried on 7.5 and 15kHz carrier frequencies. Once sonobuoys were deployed, recordings were made for at least 70 minutes unless the sonobuoy failed or the signal was lost. During recordings at CTD stations, recordings were typically made for the length of time it took to complete the CTD (4 or more hours). Data Processing: Signals were monitored in real-time during acquisition using Ishmael software (Dave Mellinger, http://www.bioacoustics.us/ishmael.html). A scrolling spectrogram (FFT size: 16384 samples, overlap: 50%, frequency range displayed: 0-1000 Hz, time scaling: 5 sec/cm) was monitored in real-time. Sounds of interest were clipped and the time and description were logged in the sonobuoy deployment data logs. Bearings to sounds were attained with a modified version of DiFarV (Mark McDonald, http://www.whaleacoustics.com ). Note that bearings to the ship noise given by DifarV are ~180 degrees off for an as yet undetermined reason (potentially deep cold water propagation effects), but the bearings to whale sounds and other sounds of interest are thought to be correct. This appears to be the case with a series of light bulb calibration tests I did, suggesting that bearings to other sounds are in fact, correct. After acquisition, recordings were also post-processed in Ishmael with two further passes, one examining 0-2.5kHz, and another monitoring 0-1kHz again, to ensure as many marine mammal sounds as possible were identified. Clips were also re-examined when necessary to ensure species were correctly identified. In instances when apparently multiple whales were calling, calculated bearings were used to determine whether the sounds came from different bearings, and hence, different whales. Dataset Format: The dataset description is in an excel workbook, with a summary sheet at the front. The summary sheet has a single line summarising each sonobuoy deployment. The sonobuoy deployment data log sheets are separated by days when the deployment began. Each is marked by date - eg 01.10 is the 10th of January. Each deployment has an initial entry and the following rows are a running log of the sonobuoy recording session. The data sheets and the summary sheet are in the following format with column headers from left to right: Observer(real time/post-processing)Summary of the sounds that occurred within the sample (70 minutes) Total recording length (in minutes) Date UTC time of deployment Initial latitude (decimal degrees) Initial Longitude (decimal degrees) Depth setting of sonobuoy hydrophone (90, 120, or 300m) National Instruments sound card gain (0, 5, or 10 times) Ship heading (true degrees) Ship speed (knots) Distance of deployment from CTD location (if applicable) UTC time of events (applies mainly to log of events in sonobuoy deployment data log) Species or sound description (applies mainly to sonobuoy deployment data log) Comments Sonobuoy type Raw data files are stored on a series of external hard drives. This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679).

  • Although the most abundant of all mammalian predators in the Antarctic marine ecosystem, crabeater seals are also one of the least understood. The most fundamental question of all - how many are there? - is the focus of an extensive international collaborative program (the Antarctic Pack-ice Seal Program, or APIS). This study supplements APIS by providing additional data on the diving behaviour and food requirements of crabeater seals, that can be used in conjunction with census data to provide information on the role of crabeater seals in the antarctic ecosystem. Winter densities and distributions of Crabeater seals were collected during 1999. Crabeater seals were most often encountered on the shelf break. The data collected include numbers of seals sighted per hour in relation to the amount of time the ship spent in each 0.5 degree grid square. This study is the first to describe the winter distribution of crabeater seals (Lobodon carcinophagus) in East Antarctica. The study was conducted in the Mertz Glacier Polynya region from July to August 1999. In total 89 crabeater seals were seen in 26 groups which ranged in size from 1 to 35 animals (mean = 3.2). The mean observed haulout density along a 200m wide strip transect was 0.108 seals per square kilometre, or 0.042 groups per square kilometre. Crabeater seals were not uniformly distributed in the polynya but selected areas of stable ice over shallow (less than 1000m) waters. We used a generalised linear model to assess the relationship of seal distribution to the physical attributes of sea ice concentration, thickness, and ocean depth. We found that ice thickness and ocean depth were the most important determinants of seal distribution. Crabeater seals occurred in areas where the ice affords them a stable haulout platform while allowing them access to Antarctic krill that live directly beneath the ice.

  • Surveys were conducted at the eastern and western ends of Heard Island during the 1987/1988 season. Burrow densities in different habitat types (vegetated and unvegetated) were determined from fixed width transects. Extensive areas at both ends of the island were surveyed and detailed information was obtained on distribution and abundance on 4 species of burrowing petrels. This work was completed as part of ASAC project 451 (ASAC_451). This work also falls under the umbrella project, ASAC 1219 (ASAC_1219).

  • Previous exploration and ornithology in the Rauer Group are reviewed. Estimates of the nesting populations of southern fulmars and Antarctic petrels are compared with censuses conducted in 1983/84 and 1984/85. Population estimates varied considerably between years, and within the same year between different observers. To remedy this situation the three islands with sympatric breeding populations of the two species were divided into counting units, which are detailed with photographs. The total populations of surface-nesting petrels are in the order of 14000 pairs of fulmars, 2500 pairs of Antarctic petrel and 400 pairs of cape petrels. Chick survival was estimated at the time of banding and varied considerable between species, islands and years. The fields in this dataset are: Location: Filla Island, Buchan Island and Hop Island Southern Fulmar Antarctic Petrel Cape Petrel Birds Counted Estimated Pairs Population Estimates Chick survival Occupied Nests Number of Birds Conversion factor

  • Collections of 23 macroinvertebrate taxa associated with Durvillaea antarctica holdfasts and 58 invertebrate taxa associated with artificial substrata collectors are described from shallow-water and intertidal habitats at Heard Island. The fauna sampled possessed strong biogeographic affinities with the Kerguelen Island fauna and, to a slightly lesser extent, the fauna recorded at Macquarie Island. The fauna possessed negligible affinity with the Antarctic. Experiments involving the offshore tethering of Durvillaea antarctica holdfasts indicated epifaunal invertebrates rapidly abandoned detached holdfasts, but that the few species surviving after one day can probably survive long periods adrift. The fields in this dataset are: Taxon (species) Distribution Locality Date Control