The ADCP used was of the type RDI Workhorse Longranger (Teledyne RD Instruments USA, Poway, California), using a four-beam, convex configuration with a beam angle of 20° and a frequency of 76.8 kHz. The instrument was moored at mean depth of 309 m in upward-looking mode and measured horizontal and vertical currents and acoustic backscatter intensity. Heading, pitch and roll, pressure and temperature data were also collected. The number of depth cells was set to 80 with a bin size of 8 m. The sampling interval was set to 1 ping per ensemble with a ping rate of about 1 ping every 4 minutes. The mooring AWI231-7 was deployed in December 2005 during R. V. Polarstern cruise ANT-XXIII/2 and recovered during R. V. Polarstern cruise ANT-XXIV/3 in March 2008.Project: Lazarev Sea Krill Study (LAKRIS), Funded by German Ministry of Education and Research