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1. Utilising data from ecosystem monitoring for managing fisheries: development of statistical summaries of indices arising from the CCAMLR Ecosystem Monitoring Program

   that missing values were unlikely to be a problem for time series of parameters that are highly ... covariance between parameters. The second part reports on a Monte Carlo simulation study that examines the ... show that missing values were unlikely to be a problem for time series of parameters that are highly ... required that allows for the three indices to be easily interpretable, that is comparable from year to ... the possibility that some parameters may not be measured in a given year due to logistic constraints ... and others phased out. These possibilities may limit the types of parameters that could be included ...

   Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 101–117 : Auteur(s): de la Mare, W.K. and A.J. Constable

2. Modelling krill recruitment

   other parameters consistent with the observed proportional recruitment parameters. A procedure is given ... for generating families of recruitment functions which are consistent with the statistical uncertainty ... : R( t ) for that simulation can be drawn from a normal distribution: 1-P I* a=-- k (28) where ... guess for the iteration should be 541. Simulation tests show that the value of S calculated using ... : Modelling Krill Recruitment from which it follows that: where At is the average number of recruits to be ... . It can be shown that: In fact no generality is lost if we put E[A,] = 1 everywhere, and so: If ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 49–54 : Auteur(s): W.K. de la Mare

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

   trawl parameters. Reliability of biomass assessments will improve with better knowledge of trawl ... high relative error. A standard method for conducting krill trawl census surveys needs to be developed ... total amount of krill entering the trawl should be carried out when selecting trawl construction. File ... . It could be proven that with two trawls operating in the same area, one could expect the coefficient ... trawls will be different. A histogram has shown that, compared with a commercial trawl, krilllength ... with different relative errors. 6. DISCUSSION It has been demonstrated that midwater trawl ... census surveys, the choice of which one to use must be made with a view to obtaining reliable ...

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

4. A preliminary investigation of the possible effects of rhizocephalan parasitism on the management of the crab fishery around South Georgia

   possible implications of parasitism for management are investigated by considering a population model that ... contrasted with the effects of harvesting healthy animals only. Equilibrium and transition dynamics of the ... non-zero prevalence of B. callosus is likely to be below that of an unexploited population with zero ... with increasing fishing mortality. This generally includes the very important assumption that both ... seems that only healthy males will be harvested. The size frequency data, albeit from limited ... limit are retained, there would be no fishing mortality on infected animals. If we further assume that ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 175–192 : Auteur(s): Basson, M

5. Moulting interval and growth of juvenile Antarctic krill fed different concentrations of the diatom Phaenodactylum tricornutum in the laboratory

   , 1.14mm. From these results, maximum daily growth rate (∆BL /IP) of juvenile krill was calculated to be ... field. Growth conditions of krill in the Southern Ocean are discussed, with special reference to the ... available food concentration. Note: The full text of this paper will be published under the above title in ... , maximum daily growth rate (6BL/IP) of juvenile krill was calculated to be 0.047 mm day-l, which is too ... krill in the Southern Ocean are discussed, with special reference to the available food concentration ... . Note : The full text of this paper will be published under the above title in Polar Biology (1987 ... THE LABORATORY T. Ikeda, P.G. Thomas (Australia) Abstract Juveni,le Antarctic krill (Euphausia ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 223-225 : Auteur(s): Ikeda, T. and P.G. Thomas

6. The choice of procedure for deciding when to close fisheries regulated by CCAMLR: a simulation model

   periods, and closes the fishery if these rates indicate that the TAC will be taken before the next report ... reporting periods are small (five days) and the reporting delay is minimal. It is recommended that in future ... fishery if these rates indicate that the T AC will be taken before the next report is received by the ... specified that: • catches should be reported to the Secretariat by 5-day reporting period, reports ... 25/IX) of the TAC the Executive Secretary shall notify Members that the fishery will be closed from ... the date shown by his calculations to be that on which the TAC will have been taken. The central ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 81–97 : Auteur(s): Agnew, D.J.

7. Annual changes in species composition and abundance of myctophid fish in the north of South Georgia (Subarea 48.3), Antarctica, during austral winters from 2002 to 2008

   . nicholsi from larvae to adults were found, suggesting that these species may have their nursery ground ... ichthyofauna in this area, although this species used to be dominant in the Antarctic coastal waters. In ... . Additionally, the size distribution of P. choriodon was unimodal, indicating that individuals in the samples ... ichthyofauna. In contrast, the current biomass of P. choriodon could be higher than that in 2002 or earlier ... . (ii) The current biomass of P. choriodon could be higher than that in 2002 or earlier in the area ... . Iwami, T. and T. Kubodera. 1990. Mesopelagic fishes collected with 10-foot IKPT in the Indian sector ... stocks, and recommended that those countries participating in the krill trawl fishery collect ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 155–163 : Auteur(s): Iwami, T., M. Naganobu, K. Taki and M. Kiyota

8. Estimating krill recruitment and its variability

   and above) of 0.339 with a standard deviation (SD) of 0.100. The corresponding result for recruitment ... nine surveys is 0.552 with a standard deviation of 0.074. A number of the assumptions needed for ... not particularly interested in their values, except that they should be consistent with what is ... for calculating R(t). If we assume that the length distributions have normal distributions with a ... mixture distribution with parameters R(t) and 8. Note that estimating R(t) and 0 requires maximising h(R ... . The problem with krill is that there is no reliable method of direct age determination. One indirect ...

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

9. Low breeding success of the Adélie penguin at Béchervaise Island in the 1998/99 season

   percent of nests with eggs failed during the three weeks following first hatch. A breeding success of 0.43 ... chicks cr6ched per nest was achieved, compared to previous seasons with higher annual breeding success ... , foraging trip duration and diet suggests that the death of chicks during the guard stage was due to an ... reduced feeding frequency. These findings contrast with observations made in 1994/95 (a season in which ... previous two seasons with low breeding success (1994/95 and 1995/96), a rate about half that of the ... the 1998/99 season (Table 5). This meal size is also larger than that of the previous seasons with ... limited also. The mean meal size of the 1998/99 guard stage was comparable to that in seasons with ... Island and persistence of pack-ice also coincided with chick starvation, suggesting that there is a ...

   Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 151–167 : Auteur(s): Irvine, L.G., J.R. Clarke and K.R. Kerry

10. Champsocephalus gunnari stock status in the South Georgia area

    and TAC for C. gunnari. Stock estimates were obtained using VPA with the following variations: mean F ... prediction the stock size value was obtained by VPA with variations using F regression methods. The ... predicted period fishing intensity was at the level of that in 1987/88; (c) For the predicted period fishing ... shows that at the currently used value of stock size and even at the lowest possible recruitment levels ... if FO.1 = 0.439. * All stock status and TAC predictions were made with the assumption that ... were obtained using VPA with the following variations: mean F, Gamma methods, Pope and Shepherd method ... obtained by VPA with variations using F regression methods. The recruitment was taken at the lowest ... fishing intensity was at the level of that in 1987/88; ( c ) For the predicted period fishing intensity ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II) : 1-18 : Auteur(s): Borodin, R. and P. Kochkin

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