Scientific echosounder data provide a predator’s view of Antarctic krill (Euphausia superba)

• Other Authors: AADC (owner), AADC, DATA OFFICER (distributor), AADC, DATA OFFICER (custodian), AU/AADC > Australian Antarctic Data Centre, Australia (hasAssociationWith), Australian Antarctic Data Centre (publisher), Australian Antarctic Division (sponsor), BRIERLEY, ANDREW S (hasPrincipalInvestigator), COX, MARTIN (collaborator), COX, MARTIN (hasPrincipalInvestigator), COX, MARTIN (author), POTTS, JOANNE M (hasPrincipalInvestigator), TERAUDS, ALEKS TERAUDS (collaborator), TERAUDS, ALEKS TERAUDS (hasPrincipalInvestigator), WOTHERSPOON, SIMON (collaborator), WOTHERSPOON, SIMON (hasPrincipalInvestigator)
• Format: Dataset
• Language: unknown
• Published: Australian Ocean Data Network
• Subjects: oceans; biota; EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES > ARTHROPODS > CRUSTACEANS > EUPHAUSIIDS (KRILL); BIOSPHERE > ECOLOGICAL DYNAMICS > COMMUNITY DYNAMICS > INDICATOR SPECIES; ECOSYSTEM FUNCTIONS > BIOMASS DYNAMICS; SCIENTIFIC ECHOSOUNDERS EK500 AND EK60; SWARMS; DISTRIBUTION; VOLUMETRIC DENSITY; ECHO SOUNDERS; R/V AA > R/V Aurora Australis; AMD/AU; CEOS; AMD; GEOGRAPHIC REGION > POLAR; OCEAN > SOUTHERN OCEAN; CONTINENT > ANTARCTICA; Antarc*; Antarctic; Antarctic Krill; Antarctica; aurora australis; East Antarctica; Euphausia superba; Southern Ocean
• Online Access: https://researchdata.edu.au/scientific-echosounder-provide-euphausia-superba/2823021

Progress Code: completed Statement: 1. These active acoustic data are of a standard expected from data collected in the Southern Ocean. There are numerous examples of seabed aliasing ('false bottom') echoes found in the 38 kHz data collected during the KAOS survey. These echoes are expected from a high ping rate sampling over rapidly changing bathymetry and have been removed during data processing. 2. The volume estimates, and hence biomass estimates, of individual krill swarms should be used with caution: the volume estimates have been calculated assuming a cylindrical swarm shape, which is likely to underestimate swarm volume, so are best used as a relative measure. Purpose The two surveys, KACTAS and KAOS, were conducted to examine predator-prey relationships between air-breathing predators and Antarctic krill. 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 - ...