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1. Length- and age-at-spawning of Antarctic toothfish (Dissostichus mawsoni) in the Ross Sea

   of D. mawsoni shows that once development begins, oocytes grow and accumulate at the cortical alveoli ... spawn at a younger age with an A 50% of 12.8 years (95% CI 11.9–14.0) or 120.4 cm (95% CI 114.8–126.7 ... limits. Hanchet et al. (2008) hypothesise that juvenile toothfish occur mainly on the shelf, with ... given size with detect- able POFs in each month showed no overall trend with time, indicating that ... old, suggesting that skip-spawning may be primarily an adolescent fea- ture, though 17% were over 18 ... propor- tion skipping appears to be age dependent, with more adolescent fish skipping than older fish ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 53–73 : Autor(es): Parker, S.J. and P.J. Grimes

2. The use of predator-derived krill length-frequency distributions to calculate krill target strength

   from land-based predators directly with automated on-board data collection systems it will be possible ... , i.e during logistic/resupply operations. This will allow a robust estimate of krill abundance to be ... suggest that temporal extrapolation of point estimates of krill biomass must be approached with caution ... with research cruises. There is increasing evidence that both the population structure and ... - butions of krill to produce a TS estimate that can be used to facilitate additional krill biomass ... conduct scientific netting in conjunction with under-way acoustic measurements can be avoided without ...

   Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 155–163 : Autor(es): Reid, K. and A.S. Brierley

3. Analysis and modelling of the Soviet Southern Ocean krill fleet

   biomass be detected? The krill distributional model begins with individual krill which are assumed to ... that could be used to track krill biomass. File:  03-Mangel.pdf ... model is developed for a survey vessel that does no fishing, but simply locates concentrations of krill ... , (ii) I recommend that fishing vessels begin to indicate in their log books the amount of between trawl ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 127–235 : Autor(es): Mangel, M.

4. Indices of prey availability near the Seal Island CEMP site: 1990 to 1996

   . Indices derived from these data indicate that although average prey density varied by a factor of almost ... of Elephant Island, and between 25 and l00 m depth. Indices of average prey density agree with ... biomass of post-spawning adults near Seal Island during the second survey of each year. It is hoped that ... these indices may be useful in modelling krill predator breeding success as a function of prey ... identified a number of indices of prey availability that could be calculated from existing datasets, and ... recommended that the feasibility of calculating such indices be investigated (SC-CAMLR, 1996). Indices of ... 100 m. This was assumed to be the foraging space of krill predators that breed at Seal Island ... indicate that although average prey density varied by a factor of almost five between 1990 and 1996, prey ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 37–45 : Autor(es): Hewitt, R.P., G. Watters and D.A. Demer

5. Age determination of Notothenia gibberifrons from the South Shetland Islands, Antarctic Peninsula subarea (Subarea 48.1)

   between false and annual checks in scales. Age determination by otolith cross sections proved to be the ... most reliable method. Mean length data at age presented here for Low I. specimens were compared with ... previous published values. This confirmed that fish from the Antarctic Peninsula subarea are smaller than ... discussed. It is expected that the Otoliths/Scales/Bones Exchange System established by CCAMLR will help to ... presented here for Low I. specimens were compared with previous published values. This confirmed that fish ... determination by otolith cross sections proved to be the most reliable method. Mean length data at age ... , Palmer Archipelago. Possible reasons for these differences are discussed. It is expected that the ... al. (1985); Shust and Pinskaya (1978) and Skora (quoted in Kock et al. 1985) worked with scales ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II) : 143-160 : Autor(es): Barrera-Oro, E.

6. Fish stock assessment survey in Subarea 48.3

   that this decline may be due to either a massed migration or high mortality. File:  03-Everson-et ... decline by comparison with results from the 1989/90 season. Other species do not show a similar dramatic ... reported from the area. It is suggested that this decline may be due to either a massed migration or high ... distance for the fish to migrate. Comparison with samples obtained in that area may confirm whether or not ... , would be surprising but consistent with the season being characterised by poor kriU availability ... 100.0 0.0 0.0 0.0 41 """ t-J Table 15: Comparison of biomass estimates (tonnes) with the results ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 25–67 : Autor(es): Everson, I., G. Parkes, K.-H. Kock, S. Campbell, Z. Cielniaszek and J. Szlakowski

7. Comparison of two methods to assess fish losses due to depredation by killer whales and sperm whales on demersal longlines

   addition to providing a methodology that could be used in other areas with depredation issues, these ... conservation issues. However, estimating the amount of resource depredated can be especially challenging when ... tonnes and 739 ± 87 tonnes of Patagonian toothfish respectively were estimated to be depredated by the ... approach, which can only be implemented when a sufficient level of by-catch species occurs, provides ... reported elsewhere in the world. In addition to providing a methodology that could be used in other areas ... ). As odontocetes leave almost no heads or lips of depredated fish that could be used to assess losses ... with odontocetes. They estimated that 571 tonnes were removed from the lines by odontocetes in the ... killer and/or sperm whales. Recent studies have indeed suggested that killer and sperm whales may be ...

   Science Journal Paper : CCAMLR Science, Volume 22 (CCAMLR Science, Volume 22) : 1–14 : Autor(es): Gasco, N., P. Tixier, G. Duhamel and C. Guinet

8. An assessment of CCAMLR measures employed to mitigate seabird mortality in longlining operations for Dissostichus eleginoides around South Georgia

   operations for Dissostichus eleginoides off South Georgia were assessed for interactions with seabirds and ... lines were laid from March to May 1997 using the Spanish double-line method. In accordance with CCAMLR ... specifications was also used, except during an experiment that attempted to assess the effectiveness of the ... during hauling using a randomised cluster sampling method, developed to allow representative data to be ... is important, and when deployment may be unnecessary. Experiments with a design similar to that ... setting, data on behavioural interactions with operations could not be taken; counts of visible seabirds ... -level Model I ANOVA with orthogonal contrasts. The total number of birds was found to be significantly ... converse, i.e. that the streamer line had no effect. Nevertheless, the low mortality rate with and ...

   Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 217–230 : Autor(es): Ashford, J.R. and J.P. Croxall

9. An index of per capita recruitment

   recruitment (PCR) is proposed such that where R 1 is the proportion of age-l animals sampled in year y and M ... assumptions that: (i) post-recruit mortality does not vary over age or between years; (ii) 100% of age-l ... age-l animals in the sample can be determined unambiguously. Normal, lognormal and uniform probability ... PCR. Distributions of PCR are skewed toward higher values such that the dynamic range of PCR is ... formulation, with the understanding that the index will be negatively biased to the extent that krill delay ... to be correlated with E ( y 2 = -0.7); i.e. conditions that are associated with low mortality tend ... are skewed toward higher values such that the dynamic range of PCR is largest with high values of R1 ... can be defined as the ratio of the number of age-l animals and the number of spawners that produced ...

   Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 179–196 : Autor(es): Hewitt, R

10. Distribution of the Soviet krill fishing fleet in the South Orkneys area (Subarea 48.2) during 1989/90

    ground was observed to be stable, and it is considered that the location was determined by certain ... fishing ground off the northwestern tip of Coronation Island. CPUE showed variability with a minimum in ... hydrodynamic characteristics of the area, for example a complex current around the islands together with ... north-east of the region. The fleet was observed drifting with the current together with krill ... the fishing ground was observed to be stable, and it is considered that the location was determined ... that the fishing ground was of major importance during all months of the 1989/90 season with only a ... one fishing ground off the northwestern tip of Coronation Island. CPUE showed variability with a ... islands together with topographically-induced effects. Except in November 1989, temporally and spatially ...

    Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 51–62 : Autor(es): Sushin, V.A

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