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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 ... being produced, and the demand for each product varies substantially from one season to the next ... In this paper, three essential questions are raised concerning the simulation study of the Japanese ... the type of products being produced, and the demand for each product varies substantially from one season ... Abstract In this paper, three essential questions are raised concerning the simulation study ... substantially from one season to the next. Finally, attention is drawn to the unrealistic behaviour ... MaTeMaTH4eCKOrO MO~e~HpOBaHH~ HCnO~b30Ba~HCb Be~H4HHbl napaMeTpOB pacnpe~e~eHH~ KPH~~, OCHOBaHHble Ha pe3y ... ~ B 3Ha4HTe~bHOH CTeneHH H3 ce30Ha B ce30H. B 3aK~I04eHHe, HaMH 6bl~O YKa3aHO Ha HeHa~e)l{HOe nOBe~eHHe Mo ...

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

2. Length-based assessment for mackerel icefish (Champsocephalus gunnari) at South Georgia

   the given harvest control rule to set a two-year total allowable catch (TAC). One issue is the accurate ... to set a two-year total allowable catch (TAC). One issue is the accurate identification of age cohorts ... these numbers forward under the given harvest control rule to set a two-year total allowable catch (TAC). One ... to project the population forward for two years under a fixed harvest rate. The target harvest rate ... is that which ensures that the exploited biomass is equal to 75% of the unexploited biomass (after two years ... ). From this target harvest rate a two-year total allow- able catch (TAC) is obtained. Given ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 129–137 : Author(s): Hillary, R.M., C.T.T. Edwards, R.E. Mitchell and D.J. Agnew

3. Length-based assessments revisited – why stock status and fishing mortality of long-lived species such as toothfish cannot be inferred from length-frequency data alone

   in Lmean and L75 from one year to the next cor- rectly predict decreases or increases in stock levels ... with missing larger fish can be obtained with two different selectivity functions: one that catches large ... . 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Immature selectivity Age (y) Se le ct iv ity ... 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Truncated mature selectivity Age (y) 0 10 20 30 ... status and fishing mortality for long-lived fish species such as Patagonian toothfish (Dissostichus ... other informative estimators for stock abundance and productivity, the review and the simulations ... highlight that interpretation of raw length-frequency data and single length-based indicators for stock ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 57–73 : Author(s): Ziegler, P.E., D.C. Welsford and A.J. Constable

4. Information on the status of fjord Notothenia rossii, Gobionotothen gibberifrons and Notothenia coriiceps in the lower South Shetland Islands, derived from the 2000–2006 monitoring program at Potter Cove

   period of 24 years which began in 1983, and at Harmony Cove in the summers of 2001to 2003. The decline ... than two decades after the end of the commercial fishery. File:  05barrera-oro-marschoff.pdf ... has continued at Potter Cove from 2000 to 2006, extending a continuous sampling period of 24 years ... than two decades after the end of the commercial fishery. ... of freedom Mean square F P (a) Notothenia rossii, total catches Years 19.8835 20 0.994173 14.6162 <0.00001 ... Error 59.3803 873 0.068019 (b) Gobionotothen gibberifrons, total catches Years 9.8124 20 0.49062 ... 42.9468 <0.00001 Error 9.9731 873 0.01142 (c) Notothenia coriiceps, total catches Years 32.4684 20 ... , relative catches Years 14296.5242 20 714.826 21.3430 <0.00001 Error 28033.11 837 33.49237 Figure ...

   Science Journal Paper : CCAMLR Science, Volume 14 (CCAMLR Science, Volume 14) : 83–87 : Author(s): Barrera-Oro, E.R. and E.R. Marschoff

5. A statistical method for estimating the level of IUU fishing: application to CCAMLR Subarea 48.3

   /2000 and 2000/01. Each year fully covered the period 1 October to 30 September, thus including one ... /2000 and 2000/01. Each year fully covered the period 1 October to 30 September, thus including one ... have been at least one encounter with an FPV in a year; no encounters in a year are interpreted as zero ... at least one encounter with an FPV in a year; no encounters in a year are interpreted as zero IUU fishing ... . Each year fully covered the period 1 October to 30 September, thus including one summer and one winter ... year was defi ned as extending from October of one year to September of the next. This is more ... with the next two FPV cruises. It is missed by the fi rst one (modelled using the encounter prob- ability ... – there would be as much chance of detection if the two cruises overlapped by one day as by eight days ...

   Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 119–141 : Author(s): Agnew, D.J. and G.P. Kirkwood

6. Length-at-age in juvenile Patagonian toothfish (Dissostichus eleginoides)

   in the length density represent different age cohorts separated by one year. File:  01ashford.pdf ... represent different age cohorts separated by one year. ... to be from fish 1+ or 2+ years old, with mean total lengths of 32.5 cm and 41.3 cm respectively ... . No difference was found between predicted and estimated ages. We conclude that the two dominant modes observed ... that the two dominant modes observed in the length density represent different age cohorts separated by one ... as 0+ years old. Fish showing the outer edge of the fi rst opaque zone were designated as one year old ... peaks shown in Figure 2, indicating that the two large peaks represent year classes containing fi sh ... 1+ and 2+ years old respectively. A much smaller peak at TL ca. 20 cm contained fi sh 0+ years old. Similar ...

   Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 1–10 : Author(s): Ashford, J., C. Jones, S. Bobko and I. Everson

7. Investigation of bias in the mark–recapture estimate of toothfish population size at South Georgia

   simulation of releases by box over multiple years. The model performed as expected with test situations ... years. The model performed as expected with test situations. It produced a near-perfect estimate ... of toothfish typically move only 20–30 km each year (Marlow et al., 2003). This paper investigates ... . 50 20 03 20 04 Release positions for animals tagged in that year 40 W 43 ... capture movement reversals – where an animal moves west one year and back east the next, for instance ... for animals tagged in that year Fishing effort (graduated by number of hooks) Position of recaputre ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 47–63 : Author(s): Agnew, D.J., G.P. Kirkwood, J. Pearce and J. Clark

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

   / Description:  The problem of acoustically identifying and estimating the sizes of two euphausiid species ... components are the mean ratios of the volume backscattering coefficients, measured at two different ... The problem of acoustically identifying and estimating the sizes of two euphausiid species ... components are the mean ratios of the volume backscattering coefficients, measured at two different ... ) ≈ 12.1afj / fi (mm). If only one frequency ratio is available (two- frequency method), its output can ... conducted in the continental shelf region: E. superba was present in only one haul (two aggregations were ... and that they can be correctly assigned to one of two possible classes ωh = 1,2 on the basis of net sampling ... - tions that the class two (ω2) is actually present but the authors estimate that it is class one (ω1 ...

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

9. Fatty acid and stable isotope analyses to infer diet of Antarctic toothfish caught in the southern Ross Sea

   of these two techniques can delineate the main prey items of Antarctic toothfish and trophic structure ... of these two techniques can delineate the main prey items of Antarctic toothfish and trophic structure ... ± SD. 70 60 50 40 30 20 10 0 % c om po si tio n ANS BEA ICX ... ANS Pleuragramma antarcticum Antarctic silverfish 0 0 20 0 20 BAM Bathyraja maccaini McCain’s skate ... Crocodile icefish 0 0 25 3 28 OCT Octopodidae Octopus 10 0 20 0 30 SZT Pogonophryne scotti Plunderfish 25 ... :0 3. 0 1. 9 ± 0. 6 2. 9 ± 0. 4 1. 8 1. 4 ± 0. 3 3. 0 3. 0 ± 0. 3 2. 4 ± 0. 6 2. 8 ± 0. 8 3. 0 ± 0. 7 C 18 :1 n9 c 20 .2 19 .5 ± 6 .4 21 .7 ± 0 .3 14 .1 30 .1 ± 2 .8 15 .2 14 ...

   Science Journal Paper : CCAMLR Science, Volume 20 (CCAMLR Science, Volume 20) : 21–36 : Author(s): Jo, H.-S., I. Yeon, C. Lim, S.M. Hanchet, D.-W. Lee and C.-K. Kang

10. Measurements of differences in the target strength of Antarctic krill (Euphausia superba) swarms at 38 kHz and 120 kHz

    differences in the mean back-scattering strength of swarms simultaneously insonified at these two frequencies ... strength at these two frequencies. The results are in good agreement with recent experimental work ... simultaneously insonified at these two frequencies in studies off the South Orkneys and Elephant Island in March ... was therefore attributed to real differences in average target strength at these two frequencies. The results ... the two integration systems. Figure 4: Figure 5: 84 50 40 ~ Z 30 « o "" ~ ~ 20 Z 10 ... target strength is one made by Foote et al. (1990) on live animals at South Georgia. Target strengths ... of encaged animals which varied in mean length from 30 to 39 mm. Calculated target strengths at 120 kHz were ... obtained by similar calibrations of these two sounders over the past three years. Spot checks on SL ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 75–86 : Author(s): Hampton, I.

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