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1. An assessment of toothfish in Subarea 48.3 using CASAL

   that there was a change in selectivities-at-age between 1997 and 1998. Accord- ingly, two ‘fleets’ were identified: one ... reporting rates are equal to 1. Estimates of recruitment by age and year class are dependent on bottom ... to be constant over all ages and years, at an assumed value of M = 0.165, which is consistent with previous ... years with different selec- tivities. However, for each fleet, the selectivities- at-age should remain ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 65–95 : Author(s): Hillary, R.M., G.P. Kirkwood and D.J. Agnew

2. Estimation of natural mortality using catch-at-age and aged mark-recapture data: a multi-cohort simulation study comparing estimation for a model based on the Baranov equations versus a new mortality equation.

   , M, using multiple cohorts and multiple years of catch-at-age and aged mark-recapture data was tested using ... the process error in predicted catch-at-age numbers. Simulations assumed 1 000 releases per year over 12 years ... . Simulations which passed catch-at-age numbers to the estimation algorithm after perturbation by observational ... functions of age of dome-shaped versus sigmoidally shaped were applied. Two alternative estimation models ... combined with a lower threshold at age 3, is usually specified so that for one or more ages it has ... multiple cohorts and multiple years of catch-at-age and aged mark-recapture data was tested using ... in predicted catch-at-age numbers. Simulations assumed 1 000 releases per year over 12 years ... . Simulations which passed catch-at-age numbers to the estimation algorithm after perturbation by observational ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 1–27 : Author(s): Candy, S.G.

3. Archival and satellite-linked data recorders

   behaviour. The records can be recovered in one of two ways: the data recorder must either be recovered ... ’'s diving behaviour. The records can be recovered in one of two ways: the data recorder must ... . These recorders are deployed on freely swimming animals and gather data on aspects of an animal’'s diving ... provides an overview of currently-available data recorders for use in research on marine animals ... animals and gather data on aspects of an animal's diving behaviour. The records can be recovered in one ... la conduite de plongee d'un animal. Les enregistrements peuvent etre recuperes de deux fa~ons ... of three complete transmissions in one satellite pass before a geolocation can be determined ... types of recorders have become available. A raw-data recorder is one in which the original data ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 475-493 : Author(s): Hill, R.D.

4. Status of krill target strength

   on aggregations of live euphausiids and should not be affected by a frequent cause of bias in single-animal ... there is an empirical basis. The theoretical estimates show a non-monotonic dependence of target strength on both animal ... size and transmit frequency, notwithstanding admitted shortcomings. Some recent single-animal ... of bias in single-animal measurements, namely thresholding. Theoretical estimates for the target strength ... boundary of the animal) change slowly along its lengthwise axis. However, one must be cautious when ... of incidence are far away from normal or "broadside". If the echo sounder and/or animals are oriented ... . 2. DEFINmONS Target strength gives a measure of backscattering or echo strength intrinsic to the scatterer ... density, where they were observed about one hour before sunset on 29 January 1984. The krill were ...

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

5. Chilean krill fishery: analysis of the 1991 season

   KRILLFISHERY DURING 1991 3.1 General Overview During the 1991 fishing season Chile sent one factory vessel ... hauls, suggesting that on average the vessel move away from a patch after five hauls. This result ... for a patch to passively drift from one fishing area to another. Even if we consider doubling the drifting ... season .,.-I 100 co ...r 90 ctl Q) "- 80 ctl .0 ::J 70 Cl) 60 E 0 '-....... 50 .c () 40 ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 273–287 : Author(s): Marín, V.H., A. Mujica and P. Eberhard

6. Sensitivity investigation of the SDWBA Antarctic krill target strength model to fatness, material contrast and orientation

   . In this study, the SDWBA TS pattern and frequency response behaviours at standard survey frequencies and animal ... and the distribution of animal orientations. Due to the high variability of TS to realistic changes in parameters ... at standard survey frequencies and animal lengths are explored via a sensitivity analysis of some important ... the organism and the surrounding seawater and the distribution of animal orientations. Due to the high ... parameters. One approach is to describe the animal’s body by digitising the main morpho- logical structures ... and lateral aspects with respect to the trans- ducer. When the animal orientation was away from these aspect ... of the new SDWBApack­ age2010 was evaluated using sensitivity tests of some parameters with regard to krill ... no ta tio n in t hi s pa pe r (S ym bo l) an d SD W B A pa ck ag e2 00 50 60 3 al ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 97–122 : Author(s): Calise, L. and G. Skaret

7. A review of the diet and at-sea distribution of penguins breeding within the CAMLR Convention Area (submitted to the 2008 Joint CCAMLR-IWC Workshop)

   their foraging range. However, most studies of penguin diet only last one or two years, which will fail ... in most cases. Two studies of pre-moult movements and of moulting distribution exist, and one ... . In Subarea 88.1, Ancel et al. (1992) fitted six birds (three female, one male, two unknown gen- der ... is the percentage of stomachs in which at least one prey item of a given type is present. This tends to exaggerate ... . These models require information on the number of predators in a population, their nutritional demands ... published information on the diet and at-sea distribution of the six penguin species that breed in the CAMLR ...

   Science Journal Paper : CCAMLR Science, Volume 19 (CCAMLR Science, Volume 19) : 75–114 : Author(s): Ratcliffe, N. and P. Trathan

8. Evidence to support the annual formation of growth zones in otoliths of Antarctic toothfish (Dissostichus mawsoni)

   the Ross Sea (CCAMLR Subarea 88.1) have been aged assuming that one translucent zone is formed annually ... mode. This indicates that the modes represented year classes and that one translucent zone is formed ... annually in otoliths of juvenile D. mawsoni. Mean fish lengths at ages 0.5, 1.5, 2.5 and 3.5 years were ... represented year classes and that one translucent zone is formed annually in otoliths of juvenile D. mawsoni ... to 4.0 cm yr-1 for fi sh aged from 15 to 30 years. It is interesting that all the points from ... represented year classes and that one translucent zone is formed annually in otoliths of juvenile D. mawsoni ... . Mean fi sh lengths at ages 0.5, 1.5, 2.5 and 3.5 years were estimated to be 14, 28, 37 and 46 cm total ... ) and capture (March). Hence, true age was assumed to be x + 0.5 years, where x is the number of translucent ...

   Science Journal Paper : CCAMLR Science, Volume 10 (CCAMLR Science, Volume 10) : 125–138 : Author(s): Horn, P.L., C.P. Sutton and A.L. DeVries

9. Integrating Count Effort by Seasonally Correcting Animal Population Estimates (ICESCAPE): a method for estimating abundance and its uncertainty from count data using Adélie penguins as a case study

   Paper Title:  Integrating Count Effort by Seasonally Correcting Animal Population Estimates ... animal count data to a common reference point of breeding chronology for species with a complex temporal ... function of sampling availability. ICESCAPE (Integrating Count Effort by Seasonally Correcting Animal ... Integrating Count Effort by Seasonally Correcting Animal Population Estimates (ICESCAPE): a method ... ; Williams et al., 2002; Pollock et al., 2004). A further adjust- ment issue, and one that interacts ... - ments are applied in an ad hoc manner. This is in part because one-off counts require relatively brief ... on researchers attempting to undertake a census at one or more breeding sites; that is, a total count of all ... present one week after the peak in egg laying (Southwell et al., 2010). Software to implement the method ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 213–227 : Author(s): McKinlay, J., C. Southwell and R. Trebilco

10. A stock assessment model of Antarctic toothfish (Dissostichus mawsoni) in the Ross Sea Region incorporating multi-year mark-recapture data

    and subsequent multi-year data of recapture of tagged fish in conjunction with fishery catch-at-age data ... -at-age data. This is the first published stock assessment of toothfish in the Ross Sea region ... Sea Region incorporating multi-year mark-recapture data Abstract / Description:  An exploratory ... , and hence a multi-year mark-recapture tagging program was initiated by New Zealand fishing vessels in 2001 ... , assuming that one translucent zone is formed annu- ally in the otoliths of this species. This ageing pro ... selectivity 10 20 30 40 50 Age Age Age Age Age Age 10 ... , one fish tagged by the fishery having moved from the RSR to the ASR, and two from the ASR to the RSR ... and fishery. Between 700 and 1 000 Antarctic toothfish from the RSR have been aged each year since 1998 ...

    Science Journal Paper : CCAMLR Science, Volume 21 (CCAMLR Science, Volume 21) : 39–62 : Author(s): Mormede, S., A. Dunn and S.M. Hanchet

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