bioacoustics 96jan jan96-feb96 Vertically integrated acoustic biomass averaged over the transect distance The vertical extent is from about 10 m below surface (varies with study) to 200 m or the bottom, whichever is shallower. Bioacoustics data were previously presented as estimates of biomass with a specific target strength model. In response to requests for data to be available for processing with different target strength models, the raw binary files generated by Biosonics software (V3) are now available. Due to their large size, they are available upon request from the PI of origin. analog voltage signal The primary derived variable is acoustic biomass. Two to three short (1-2 km) acoustic transects were conducted in conjunction with net tows at each Palmer LTER station occupied during a cruise. Longer and more closely spaced acoustic transects were conducted within the foraging range of the Adelie penguins nesting near Palmer Station. The Palmer LTER uses Biosonics equipment to collect hydroacoustic data, and several software programs to analyze the data. Acoustic measurements were made along several short (1-2 km) transects which were centered over a discrete location. Transects were conducted within 4 hours of the time other LTER data sets were collected. Each acoustic transect was matched with a net tow to allow identification of potential scatterers and the size distribution of Euphausia superba, the dominant scatterer. Antarctic krill are usually the dominant sound scatterer in the Southern Ocean. bioacoustics, acoustic biomass, antarctic krill, palmer lter ~lter/lterdata Robin M. Ross, Langdon B. Quetin Robin M. Ross, Langdon B. Quetin Langdon B. Quetin, Janice Jones and team Langdon B. Quetin, Janice Jones Janice Jones Janice Jones Langdon B. Quetin May 1998 BioSonics (1990) BioSonics Echo Signal Processor Operators Manual. BioSonics, Inc., Seattle, WA, 373 pp. Lascara (1996) Seasonal and mesoscale variability in the distribution of Antarctic krill, Euphausia superba, west of the Antarctic Peninsula. Ph. D. Thesis, Old Dominion University. 167 pp. Greene, C. H., T. K. Stanton, P. H. Wiebe and S. McClatchie (1991) Acoustic estimates of Antarctic krill. Nature 349: 110. Nero, R. W. and J. J. Magnuson (1989) Characterization of patches along transects using high resolution 70 kHz integrated acoustic data. Canadian Journal of Fisheries and Aquatic Sciences 46: 2056-2064. Wiebe, P. H., C. H. Greene, T. K. Stanton and J. Burczynski (1990) Sound scattering by live zooplankton and micronekton: empirical studies with a dual-beam acoustical system. Journal of Acoustical Society of America 88: 2346-2360.