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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 ... . At the same frequency for aggregations with mean lengths in the range 41 to 47 mm the mean single ... -krill target strength is in the range-76 to-81 dB. File:  08-Kasatkina.pdf ... the mean single-krill target strengths range from-71 to-77 dB at 20 kHz. Trawl hydroacoustic method ... . Mean length of specimens was 49.9 mm and mean weight was 0.814 g. Males were dominant in the catches ... metal frame in the shape of a truncated pyramid. The hydroacoustic transducer connected to the impulse ... difraction zone in the area being measured and the optimal ratio of target sizes to the transducer size ... • hydroacoustic transducer (piezoceramic) • width of directional diagram at 3 dB - 10°. The cage was cubic in ...

   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. Growth and natural mortality of Patagonian rockcod (Patagonotothen guntheri shagensis) from Shag Rocks shelf

   -weight data of research and fishery survey cruises in the Shag Rocks area from 1978 to 1986. The natural ... of natural mortality M=0.8 was used in calculations and the optimal age and length for harvesting ... mortality rate was assessed by six different methods and was within a range of 0.63 to 1.06. The mean value ... shagensis) from Shag Rocks shelf Abstract / Description:  The parameters of Bertalanffy’s growth equation ... within a range of 0.63 to 1.06. The mean value of natural mortality M=0.8 was used in calculations and ... P.g. shagensis before the beginning of fishing is shown in Figure 2. The mean age of fish was ... Resources of the Atlantic Ocean. M., Nauka. pp. 276-286 (In Russian). 117 Table 1: Mean length of P.g ... calculated by using age and length-weight data of research and fishery survey cruises in the Shag Rocks ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/6 (Selected Scientific Papers, SC-CAMLR-SSP/6) : 111–121 : Autor(es): Shlibanov, V.I.

3. Can we use discriminant function analysis to sex penguins prior to calculating an index of a morphometric characteristic?

   avoiding the necessity of sex determination. However, uncertainty in sex ratios can lead to considerable ... index of a morphometric characteristic? Abstract / Description:  In sexually dimorphic species ... discriminant analysis can be used to determine the sex of individuals, it is only able to correctly sex a ... using discriminant analysis. When discriminant functions are able to correctly determine the sex of ... expressed in terms of the true mean and standard deviation: ~1 = ~ - ca for females, ~3 =~' + ca for ... , take the case of body weight in Table 2. Taking the expected combined mean to be halfway between the ... = 0.021 from equation 6. Therefore, if we observe a change in the mean of 10%, 2.1 % of this may be due ... used to indicate that there was a change in the combined mean of the characteristic, as it may have ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 259–272 : Autor(es): Agnew, D.J.

4. Results of fish stock assessment survey, South Georgia region, November - December 1986

   rossii and Patagonotothen brevicauda guntheri were an order of magnitude lower than observe by Kock in ... 1985. Abundance of Dissostichus eleginoides and Pseudochanichthys georgianus appeared lower in 1986/87 ... Champsocephalus gunnari were larger in 1986/87 than 1984/85, probably due to good recruitment of 1983/84 and 1984 ... Paper Title:  Results of fish stock assessment survey, South Georgia region, November- December ... established in 1984 when the Commission for the Conservation of Antarctic Marine Living Resources adopted ... %, respectively, of the 1984/85 estimates. Specimens ranged in length from 27-68 cm, with a mean length of ... modes in the length frequency distribution of 15, 25, 34, 42 and 50 cm correspond to published mean ... . 1985). Of the major finfish resources, the decline in abundance of Notothenia rossii has been the ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 143-183 : Autor(es): Gabriel, W.L.

5. Determination of Antarctic krill acoustic back-scattering cross-section

   -section of back-scattering of krill. The target strength can be determined in situ by measuring the echo ... signal from one specimen resolved by the hydroacoustic instrument. By calculating the mean level of the ... directivity diagramme of the antenna and the mean level of the standardized echo signal, it is possible to ... / Description:  When determining the density krill of concentrations it is necessary to know the acoustic cross ... (7) in (10) and (4) in (7) we obtain the expression for determining the mean value of acoustic back ... the distance. The mean and maximum length of krill are determined from data collected in sample ... -section of back-scattering of krill. The target strength can be determined in situ by measuring the echo ... , Pa antenna sensitivity in reception, V/Pa amplification of the receiver directivity function ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 141-152 : Autor(es): Protaschuk, V.A. and T.A. Lukashova

6. A hybrid approach to acoustic classification and length estimation of krill

   the acoustic estimates of species and sizes to net samples collected during three surveys conducted in ... components are the mean ratios of the volume backscattering coefficients, measured at two different ... / Description:  The problem of acoustically identifying and estimating the sizes of two euphausiid species is ... are derived by integrating the individual decisions. The size structure of the classified aggregation ... ) j if f is the geometric mean of the acoustic wave number (c = speed of sound in m/s; fj , fi ... and moulting (Bucholz, 1982). (ii) Differences in swimming behaviour: The mean swimming angle of ... with mean value μ and standard deviation σ in dB. The pair of Gaussian-distributed pattern classes ... differently within fi shed aggregations. Another shortcom- ing is that the acoustic mean length of krill in ...

   Science Journal Paper : CCAMLR Science, Volume 11 (CCAMLR Science, Volume 11) : 33–58 : Autor(es): Azzali, M., I. Leonori and G. Lanciani

7. Homogeneity of Adélie penguins as krill samplers

   penguins in the length of krill eaten, using data from Esperanza Bay. The variance component-0.26 was not ... penguins to estimate parameters of the prey population without discriminating by sex, weight or other ... Paper Title:  Homogeneity of Adélie penguins as krill samplers Abstract / Description:  A nested ... ANOVA design was used to measure the variance component due to differences between individual Adélie ... variance component due to differences between individual Adelie penguins in the length of kriU eaten ... important factor in assimilation rates and energetic requirements of these birds. The analysis of length ... length class should take into account this fact. Heterogeneity between the lengths of krill in different ... . These might be used in the assessment of penguin energetic requirements as well as to statistically ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 253–257 : Autor(es): Marschoff, E. and B. Gonzalez

8. Target strengths of Antarctic krill (Euphausia superba)

   Paper Title:  Target strengths of Antarctic krill (Euphausia superba) Abstract / Description:  The ... and 120 kHz in a sheltered bay at South Georgia. The results indicate that the Target Strength values ... Mean Volume Backscattering Strength of encaged aggregations of swimming krill have been measured at 38 ... in estimated mean target strengths, the general finding of this study is clear. The target ... attempt to quantify its abundance in 1981 over part of its area of occurrence in the Southern Ocean ... , defrosted or otherwise preserved specimens, in fresh water as well as sea water. In addition the state of ... measurements of the target strength of E. superba, made in January and February 1988. These were performed on ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 265–279 : Autor(es): Everson, I., D.G. Bone, J.L. Watkins and K.G. Foote

9. Status of krill target strength

   Paper Title:  Status of krill target strength Abstract / Description:  Empirical estimates for the ... aggregations of live euphausiids and should not be affected by a frequent cause of bias in single-animal ... is an empirical basis. The theoretical estimates show a non-monotonic dependence of target strength ... recommendations are made for future, improved determinations of krill target strength. Based on the comparisons ... performed near the South Orkney Islands in May 1983 on krill of mean length 44.7 mm, for which the ... South Georgia in June 1983 onkrill of mean length 49.9 mm, with effective mean TS of -72 dB. The ... Hampton, 1989). In order to convert measurements of echo strength to biological quantities, such as the ... 102 ! :/ interest in krill biomass, as witnessed, for example, by the scale of international ...

   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

10. Review of length-weight relationships for Antarctic krill

    euphausiid species), are listed for ash-free dry weight, dry weight, and wet weight. The accuracy of length ... taken into account. The influence of seasonal changes on length-weight relationship parameters is ... Paper Title:  Review of length-weight relationships for Antarctic krill Abstract / Description ... discussed. Recommendations for possible uses of reviewed length-weight relationships are presented. File ... maturity stages in improving the precision of calculating weight from length data. Since Morris et al ... comprehensive study, Morris et al. (1988) analysed the improvement in the precision of predictions using length ... classification of 'males', 'gravid females' and 'non-gravid females' increases the precision in prediction for ... , the simple division of krill into male and female categories is of little practical use in improving ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 145–155 : Autor(es): Siegel, V.

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