bioacoustics 9596pal nov95-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 avail,able for processing with different target strength models, the raw binary files generated by Biosonics software (V3) are being made available. Due to their large size, they are available upon request from the PI of orgin. The raw signal is an analog voltage while the primary derived variable is acoustic biomass. Two acoustic transects of about 3.5 to 5 km each were conducted weekly, from Arthur Harbor out to the 200 m contour line (A-E), and on the east side of Wylie Bay, along the outside of the islands (Humble to Spume Islands) near Palmer Station and within the 3.7 km boating limit (F-J). The Palmer LTER uses Biosonics equipment to collect hydroacoustic data, and several software programs to analyze the data. Acoustic transects were done within 6 hours of a series of LTER stations along the same transect. Data from these stations includes hydrographic, optical, and pigment. Targeted tows in the same week confirmed the composition of possible acoustic scatterers. Antarctic krill are usually the dominant sound scatterer in the Southern Ocean. Target and standard tows during the week verify the composition of the dominant scatterers. bioacoustics, acoustic biomass, antarctic krill, palmer lter ascii, comma separated variable format ~lter/lterdata robin's mac Robin M. Ross, Langdon B. Quetin none Robin M. Ross, Langdon B. Quetin Janice Jones, Robin M. Ross Robin M. Ross, Langdon B. Quetin 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. Yearly calibrations are conducted to ensure that the equipment has not changed markedly during the period of use.