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1. Target strengths of krill at 136 and 20 kHz

   . Ensonification of encaged live krill. For aggregations with mean lengths from 45 to 50 mm the mean single-krill ... the mean single-krill target strengths range from-71 to-77 dB at 20 kHz. Trawl hydroacoustic method ... . For aggregations with mean lengths from 47 to 50 mm the mean target strengths ranged from-71 to-75 dB ... . At the same frequency for aggregations with mean lengths in the range 41 to 47 mm the mean single ... in order to guarantee that the cage had become completely saturated and that there was no air ... . 1985. Report of the Post-FIBEX Workshop in August 1984. BIOMASS Report Series No. 40. ANON. 1986 ... No.ofKriU TS (cage + krlll), Krill Krill Parameters No. in the Cage dB TS,dB L (mm) sd P 1 100 -45.99 ... aggregations with mean lengths from 45 to 50 mm the mean single-kriU target strengths range from -68 to -69 dB ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 141–157 : Autor(es): Kasatkina, S.M.

2. Differentiation of independent populations of Antarctic krill

   circulation. On the basis of the review, it is suggested that there is probably one composite population of E ... . superba in the Southern Ocean subdivided into several independent sub-populations. The number of these sub ... -populations is expected to correspond with the number of quasi-stationary cyclonic water circulations. At ... development due to homogeneity of physical environmental parameters. To the best of our knowledge, no ... no papers dealing with the subject of variability of krill inhabiting different areas of the ... and morphophysiological variability of krill and Antarctic water circulation. On the basis of the ... review, it is suggested that there is probably one composite population of E. superba in the Southern ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 275-281 : Autor(es): USSR

3. Midwater trawl catchability as an aspect of a quantitative assessment of krill biomass conducted using a trawl census survey

   variable which depends on both the behavioural and distributional characteristics of the target species and ... midwater trawls and small research trawls, in this case using an Isaacs-Kidd trawl, demonstrated the ... futility of using the latter for trawl census survey biomass assessments due to their highly variable ... catchability over the survey area and also because the biomass estimates thus obtained were characterised by ... contains no errors, the relative error in the biomass estimate from formulas 1 and 2 will be calculated as ... catchability no less than ~ x(P) = 0.1, it would be necessary to carry out over the study area 20 hauls with a ... . Kasatkina* Abstract Midwater trawl catchability is a variable which depends on both the behavioural and ... distributional characteristics of the target species and trawl parameters. Reliability of biomass assessments ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 257–272 : Autor(es): Kasatkina, S.M.

4. Detection and quantitative estimation of krill concentrations by hydroacoustic instruments

   instruments Abstract / Description:  The limited capabilities of existing hydroacoustic instruments in ... in areas surveyed. The task of detecting surface concentrations of krill can be solved with the help ... of towed acoustic antennae. The practical possibility of detecting dispersed krill by hydroacoustic ... instruments was established on board the research vessel Odissey during the international expedition under the ... condition ensures reliable reception and registration by the recorder and integrator of no less than one ... ESTIMATION OF KRILL CONCENTRATIONS BY HYDROACOUSTIC INSTRUMENTS K.I. Yudanov (U.S.S.R.) Abstract The ... concentrations of krill lead to considerable underestimates of krill biomass in areas surveyed. The task of ... detecting surface concentrations of krill can be solved with the help of towed acoustic antennae. The ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 123-139 : Autor(es): Yudanov, K.I.

5. Areas of seabed within selected depth ranges in CCAMLR Subarea 48.3, South Georgia

   and deeper than 500 m have been estimated from nautical charts. The results are presented by CCAMLR ... Georgia and the whole of Subarea 48.3. An asterisk (*) indicates that there are no reported soundings for ... estimated from nautical charts. The results are presented by CCAMLR fine-scale reporting areas. Resume ... KapTaM 6bIJla onpe,lleJleHa nJlOlIla,llb yqaCTKOB MopCKoro ,llHa no r Jly6HHHbIM ropH30HTaM OT 50 ,llO ... 250 MeTpoB, OT 250 ,llO 500 MeTpoB H rJly6)1{e.Pe3YJlbTaTbI npe,llcTaBJleHbI no MeJlKOMaCIIITa6HbIM ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 459–466 : Autor(es): Everson, I. and S. Campbell

6. Estimating confidence intervals for fish stock abundance estimates from trawl surveys

   estimates of abundance obtained from trawl surveys conducted by means of the swept area method, using ... likelihood ratios from Aitchison's delta distribution. Simulation tests of the method show that unbiased ... estimates of density and biomass can be obtained and that the estimated confidence intervals have close to ... the nominal coverage probability. Performance deteriorates in cases where few of the hauls contain ... by means of the swept area method, using likelihood ratios from Aitchison's delta distribution ... . Simulation tests of the method show that unbiased estimates of density and biomass can be obtained and that ... the estimated confidence intervals have close to the nominal coverage probability. Performance ... deteriorates in cases where few of the hauls contain fish and the coefficient of variation (CV) is high. The ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 203–207 : Autor(es): de la Mare, W.K

7. Status of krill target strength

   Paper Title:  Status of krill target strength Abstract / Description:  Empirical estimates for the ... measurements, namely thresholding. Theoretical estimates for the target strength are derived from the deformed ... is an empirical basis. The theoretical estimates show a non-monotonic dependence of target strength ... high signal-to-noise-ratio conditions, are consistent with the general pattern. Several specific ... date, there is no theory that adequately describes the scattering of sound by zooplankton. The animals ... ) involved detennination of krill density by trawling. No comments are made by the author on this sampling ... , so no assessment can be made here as to the accuracy of this density detennination. In two studies ... are very few data concerning the distribution of orientation and no specific information on shape ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 101–126 : Autor(es): Foote, K.G., D. Chu and T.K. Stanton

8. Acoustic data analysis and models of krill spatial distribution

   / Description:  Acoustic data obtained on 4-5 January 1987 aboard the R/V Professor Siedlecki were used in three ... (spatial autocorrelation of krill biomass) and the frequency distribution of krill biomass estimate. The ... wavenumber spectrum resembles a white noise at scales of 2-20 km, although at scales smaller than 1 km the ... spectrum appears to lose its power significantly. The semivariance of biomass does not vary significantly ... obtained on 4-5 January 1987 aboard the RN ProfesSor Siedlecki were used in three descriptors of krill ... autocorrelation of krill biomass) and the frequency distribution of krill biomass estimate. The wavenumber ... spectrum resembles a white noise at scales of 2-20 km, although at scales smaller than 1 .km the spectrum ... appears to lose its power significantly. The semivariance of biomass does not vary significantly over ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 311–329 : Autor(es): Morin, A., A. Okubo and K. Kawasaki

9. Selectivity of commercial and research trawls in relation to krill

   / Description:  This paper describes the results of fishing a single krill aggregation with a commercial trawl ... RT 72/308 and an Isaacs-Kidd midwater research trawl (IKMT). The commercial trawl catches contained ... more large krill (35-58 mm) than catches of the research trawl (30-54 mm). The maximum difference in ... krill length composition was observed between catches made by the research trawl, while in commercial ... m along the belly line. The trawl bag has no rope or large-mesh sections. Therefore, the effective ... This paper describes the results of fishing a single krill aggregation with a commercial trawl RT 72 ... /308 and an Isaacs-Kidd midwater research trawl (IKMT). The commercial trawl catches contained more ... large krill (35-58 mm) than catches of the research trawl (30-54 mm). The maximum difference in mean ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 161–169 : Autor(es): Kasatkina, S.M

10. Estimating krill recruitment and its variability

    likelihood method is developed for the decomposition of krill density-at-length data into the proportion of ... surveys in the South Atlantic and the Indian Ocean sectors of the Southern Ocean give a mean recruitment ... rate for 1+ krill (the ratio of the number of krill aged one year to the number of krill aged one year ... and above) of 0.339 with a standard deviation (SD) of 0.100. The corresponding result for recruitment ... . The problem with krill is that there is no reliable method of direct age determination. One indirect ... frequency data have no unusual statistical properties. The usual method assumes that length frequency data ... 7050 Tasmania, Australia Abstract A maximum likelihood method is developed for the decomposition ... of krill density-at-length data into the proportion of recruits in a population sampled by a net ...

    Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 55–69 : Autor(es): de la Mare, W.K

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