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1. Brief comments on the simulation study made by Professor Butterworth on krill fishing by an individual Japanese trawler

   questions are raised concerning the simulation study of the Japanese krill fishery carried out by ... during FIBEX surveys. Since very little searching time is spent on layers, the utility of searching time ... data appears doubtful. Secondly, the utility of indices based on the sum of primary and secondary ... searching times (PST+SST) is also doubtful because SSTs are markedly dependent upon the type of products ... simulation as meaningful as possible by using most of the information available at present. His model ... in the vicinity of trawlers at that time, they return to the swarm(s) which were previously detected ... Abstract In this paper, three essential questions are raised concerning the simulation study of the ... is spent on layers, the utility of searching time data appears doubtful. Secondly, the utility of ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/6 (Selected Scientific Papers, SC-CAMLR-SSP/6) : 347–350 : Autor(es): Ichii, T. and Y. Endo

2. 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 ... followed in the method developed here. The delta distribution consists of a discrete probability at the ... distribution with one degree of freedom, at the a probability level. An asymptotic confidence interval for ... vectors of biomasses b ,... bk at the roots of function ( 1 3 ) are regarded as nuisance parameters ... calculating asymptotic confidence intervals for estimates of abundance obtained from trawl surveys conducted ...

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

3. CCAMLR ecosystem monitoring and a feedback management procedure for krill

   attributable to loss of prey through fishing activities. The principal fishery in the CCAMLR Convention Area is ... 1.5 million tonnes in the Atlantic Sector of the CCAMLR Convention Area at the Tenth Meeting of the ... kriU at the specified level cause the health of predator populations to decline below an acceptable ... or of the community at large. While some attempts have been made to describe positive and negative ... aspects of change in predator populations and communities (e.g., Croxall et al., 1988) and the scale at ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 345–350 : Autor(es): Constable, A.J.

4. A rationale for conservation areas within Antarctic waters

   :  The application of potential conservation measures listed in Article IX 2 of the Convention requires ... ‘the designation of regions and sub-regions based on the distribution of populations of Antarctic ... , first priority has been given to surface circulation of southern waters and the distribution of krill ... . This has been supplemented by (limited) information on the distribution of major consumers including ... , contains a unit stock of at least the target species, or preferably, a largely self-contained ecosystem ... circulation, he suggested at least six cyclonic systems, although the longitudinal limits of each were not ... based on knowledge available at the time, of the distribution of the larger baleen whales during the ... ), while sei and minke whales were little segregated at all. For a re-examination of the distribution ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 513-535 : Autor(es): Chittleborough, R.G.

5. Low genetic diversity in the Antarctic toothfish (Dissostichus mawsoni) observed with mitochondrial and intron DNA markers

   digests of nine sub-regions of the mitochondrial genome. Polymorphisms were found in four of seven introns ... areas. Direct sequencing of cytochrome b (665 bp) and the left domain of the control region (639 bp ... from 200–500 mg of muscle tissue by homogenisation and digestion with proteinase-K at 55°C for 4 h ... air dried and resuspended in 40 µl sterile water and stored at –20°C. Two classes of markers, mtDNA ... Rousset, 1995). There was no signifi cant heterogeneity at any of the loci (CK6 χ2 = 2.36, P = 0.31; CK7 ... ) OBSERVED WITH MITOCHONDRIAL AND INTRON DNA MARKERS P.J. Smith National Institute of Water and ...

   Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 43–51 : Autor(es): Smith, P.J. and P.M. Gaffney

6. Modelling catch and effort data using generalised linear models, the Tweedie distribution, random vessel effects and random stratum-by-year effects

   CCAMLR areas is to model the haul-by-haul ratios of catch to effort as the response variable in a ... generalised linear model (GLM) with a square-root link function and a unit variance function. A time series of ... ) estimated using a profile extended quasi-likelihood, and a log link function with log of effort as an offset ... model (GLMM), in order to provide more efficient estimates of the standardised CPUE time series and more ... -count variable with mean τ (e.g. the number of fi sh in the haul). Since N can be zero at a frequency ... determined by the Poisson distribu- tion with mean τ, the distribution of Z has non-zero mass at Z = 0. The ... . Butterworth, B.P. Watkins and D.G.M. Miller. 2002. A fi rst attempt at an assess- ment of the Patagonian ... eleginoides) for CCAMLR areas is to model the haul-by-haul ratios of catch to effort as the response variable ...

   Science Journal Paper : CCAMLR Science, Volume 11 (CCAMLR Science, Volume 11) : 59–80 : Autor(es): Candy, S.G

7. Response to Everson (2008)

   before applying the dB difference technique to identify krill. At a nominal survey speed of 10 knots ... Estimating standing stock of krill using maximum Entropy imagE rEconstruction A.S. Brierley and B.G ... . Heywood Pelagic Ecology Research Group Gatty Marine Laboratory University of St Andrews, Scotland, UK ... Email – asb4@st-and.ac.uk S.F. Gull Astrophysics Group Cavendish Laboratory University of Cambridge ...

   Science Journal Paper : CCAMLR Science, Volume 15 (CCAMLR Science, Volume 15) : 195–198 : Autor(es): Brierley, A.S., B.G. Heywood and S.F. Gull

8. Choosing distance between acoustic survey tacks

   on the basis of typical size of the surveyed region, allowable relative error in the biomass estimate ... , and the variation coefficient of the density values of the krill concentrations. It is recommended ... characteristics of the field. It was recently recommended to fix tacks at a distance somewhat exceeding the ... . Comparison of biomass estimates obtained by different methods at different tack frequencies indicated that ... on the basis of typical size of the surveyed region, allowable relative error in the biomass ... estimate, and the variation coefficient of the density values of the krill concentrations. It is ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 153-164 : Autor(es): Kalikhman, I.L., Z.I. Kizner, B.R. Zaripov and W.D. Tesler

9. Otolith and body size relationships in bigeye grenadier (Macrourus holotrachys) in CCAMLR Subarea 48.3

   CCAMLR Subarea 48.3 Abstract / Description:  A large sample of otoliths from bigeye grenadier (Macrourus ... 48.3 was measured and weighed, and the usefulness of otoliths as predictors of fish size was determined ... . Otolith mass provides good estimates of fish length, whereas otolith length and width measurements provide ... less accurate estimates of fish length. Seasonal variations in fish mass with reproductive condition ... Survey (BAS) laboratory at King Edward Point, South Georgia. Fish were identifi ed using the methods of ... at King Edward Point. We would also like to acknowledge the dedication of all of the observers who ... . Croxall and D.W. Doidge. 1983. Fish prey of the Antarctic fur seal Arctocephalus gazella at South ... . Inter- annual variation in the diets of two albatross species breeding at South Georgia: implications ...

   Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 133–143 : Autor(es): Morley, S. and M. Belchier

10. Do krill and salps compete? Contrary evidence from the krill fisheries

    Peninsula. Interannual and seasonal variability of the timing, duration and intensity of salp blooms and the ... presence of green krill were analysed. No relationship between salp density and the proportion of green ... area, the proportion of green krill was high only when salp density was extremely low. However, no ... salp density at the krill fishing ground was most often observed in February and March, the peak of ... ). This unregulated filtration of all particles may lead to fatal clogging at concentrations of ... , than in hauls containing salps at any density. Concentration of particles in the seawater or the ... r Figure 2: Seasonal variability of average proportion of green krill at the fishing ground fro1 ...

    Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 205–216 : Autor(es): Kawaguchi, S., T. Ichii, M. Naganobu and W.K. de la Mare

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