Tokarev Yu.N., Vasilenko V.I., Zhuk V.F., Sokolov B.G., Slipetsky D.Ya. «Acoustical estimation of the antarctic krill swarms spatial distribution and biomass» Морской экологический журнал, № 1, с. 5-14 (2005)

The method of acoustic express-evaluation of the krill (Euphausia superba Dana) population spatial structure and determination of its accumulations biomass, with 80 kHz echosounding frequencies has been worked out during the 7-th Ukrainian Antarctic expedition. The method error does not exceed 10%, which permits to recommend it for usage under the Antarctic krill fishery conditions. The principal possibility to acoustically express-evaluate chorological structure of the Antarctic krill population has been shown. Formation by krill of dense accumulations of different form, elongated for 6 miles, appeared to be an expressed feature of krill behaviour during observations. The school type in krill distribution was observed as well. Parallel to this the accumulations location depth varied in the limits of 10–70 m, and their height made from 5 to 50 m.