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

   Paper Title:  An assessment of CCAMLR measures employed to mitigate seabird mortality in ... longlining operations for Dissostichus eleginoides around South Georgia Abstract / Description:  Longlining ... operations for Dissostichus eleginoides off South Georgia were assessed for interactions with seabirds and ... the effectiveness of measures employed by CCAMLR to mitigate seabird mortality. Following an agreement ... lasting 20 minutes each over an observation period of 1.5 to 2 hours. Observations were made from the ... . For sampling units, the mother line was divided into lengths of 30 coils using sequences of three ... marked connecting lines. At the start of hauling, four 30-coil lengths were randomly selected for ... April, an experiment was conducted for one month to assess the effectiveness of the streamer line in ...

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

2. Target strengths of krill at 136 and 20 kHz

   Paper Title:  Target strengths of krill at 136 and 20 kHz Abstract / Description:  Estimation of ... . Ensonification of encaged live krill. For aggregations with mean lengths from 45 to 50 mm the mean single-krill ... target strengths range from-68 to-69 dB at 136 kHz. For aggregations with mean lengths from 43 to 47 mm ... the mean single-krill target strengths range from-71 to-77 dB at 20 kHz. Trawl hydroacoustic method ... strengths range from -71 to -77 dB at 20 kRz. Trawl hydroacoustic method. For aggregations with mean ... the ability of krill to reflect sound ("reflectability") has been going on for more than ten years ... Group on Krill called for a review of all current works on determination of krill target strength (TS ... krill with an average length of 45 to 50 mm, while at a frequency of 20 kHz target strength values of ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 141–157 : Autor(es): Kasatkina, S.M.

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

   most reliable method. Mean length data at age presented here for Low I. specimens were compared with ... Paper Title:  Age determination of Notothenia gibberifrons from the South Shetland Islands ... between false and annual checks in scales. Age determination by otolith cross sections proved to be the ... previous published values. This confirmed that fish from the Antarctic Peninsula subarea are smaller than ... ), however, no data were obtained for the first 1-4 year age groups. Therefore, growth curves were not ... presented here for Low I. specimens were compared with previous published values. This confirmed that fish ... species. Up to now several papers have been published on the age and growth of N. gibberifrons. Kock et ... , gave age-length information for a population sampled in South Bay (Palmer Archipelago, Antarctic ...

   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.

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

   observed in the length density represent different age cohorts separated by one year. File:  01ashford.pdf ... Paper Title:  Length-at-age in juvenile Patagonian toothfish (Dissostichus eleginoides) Abstract ... the length modes observed. Length densities by age were compared graphically with the overall length ... density observed. Additionally, ages were predicted for each fish based on length, and compared with ages ... 50 60 70 80 90 Fr eq ue nc y 40 30 20 10 0 ... 80 60 40 20 0 Estimated age (years) 0 2 4 6 ... qij is the proportion of fi sh of age i within an age subsample for a length j. RESULTS Of the ... sample is shown in Figure 2. The length-frequency plots for cohorts of estimated age 0+ to 4+ years are ...

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

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

   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 ... maturation stage by approximately May each year. The age at 50% spawning for females on the Ross Sea slope ... stage for at least one year. Individual oocytes are then recruited into the vitellogenic phase over at ... Paper Title:  Length- and age-at-spawning of Antarctic toothfish (Dissostichus mawsoni) in the ... L50% for the hindcast ogive. 0 10 20 30 40 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Age (y) P ro po rti ... Age (years) 0 10 20 30 ... f fi sh Age (years) 5 10 15 20 25 30 ... age at 50% spawning for females on the Ross Sea slope region is 16.6 years (95% CI 16.0–17.3) or ...

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

6. Age–length composition of mackerel icefish (Champsocephalus gunnari, Perciformes, Notothenioidei, Channichthyidae) from different parts of the South Georgia shelf

   the South Georgia area. An analysis of the spatial distribution of C. gunnari size and age groups over ... similar age-length composition for young fish inhabiting areas to the west of the island and near Shag ... the age of 2-3 years. It has been found that, by number, recruits represent the largest part of the ... to live not only in off-bottom, but also in pelagic waters, an earlier age of sexual maturity ... addition, for those years for which data on age-length composition were available, the size composition ... dominant age groups was characteristic for C, gulznnri, not only during years of systematic intensive ... sometimes observed to be completely absent for several years (e.g. 1982 year class) (Figure 4). A ... . An analysis of the spatial distribution of C. giirzrznri size and age groups over the eastern ...

   Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 133–146 : Autor(es): Frolkina, G.A

7. A preliminary assessment of age and growth of Antarctic silverfish (Pleuragramma antarcticum) in the Ross Sea, Antarctica

   -growing with a moderate longevity; the maximum estimated age was 14.3 years. Von Bertalanffy parameters ... derived for both sexes combined are: L ∞ 22.1 cm SL; K 0.167 y –1; t 0 –0.4 years. Parameter estimates ... Paper Title:  A preliminary assessment of age and growth of Antarctic silverfish (Pleuragramma ... were also derived for the sexes separately. Female Antarctic silverfish appear to reach a larger size ... 25 0 3 6 9 12 15 Age (years) St an da rd le ng th (c m ) 0 5 10 15 20 25 0 3 6 9 12 ... 5 6 7 8 9 10 11 12 13 14 Age (years) Fr eq ue nc y Age (years) Fr eq ue nc y 50 40 30 20 ... = 0.96) and 4.1% for weight (n = 20, r2 = 0.98). Age and growth Otolith preparation Otoliths were ... growth for about eight years, after which the growth rate declines. The maximum recorded age was 14.3 ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 75–86 : Autor(es): Sutton, C.P. and P.L. Horn

8. Age, growth and mortality of Patagonian toothfish (Dissostichus eleginoides) caught off Kerguelen

   otoliths from reference collections were used to measure precision; relative bias for the age data was ... estimated to be –0.6 years and residual variance 2.9. Age distributions of toothfish caught by two vessels ... depth or season. Age–length keys were constructed for use in assessing toothfish catches made by ... Paper Title:  Age, growth and mortality of Patagonian toothfish (Dissostichus eleginoides) caught ... Estimated age (years) 0 10 20 30 40 50 T ot al le ng th ( cm ) 0 20 40 60 80 100 120 140 (a ... ge ( ye ar s) 0 10 20 30 40 50 Reference age (years) 0 10 20 30 40 50 E st im at ed a ... estimated for reader R2. 0 10 20 30 40 50 T ot al le ng th ( cm ) 0 20 40 60 80 100 120 140 ... for the age data was estimated to be –0.6 years and residual variance 2.9. Age distributions of ...

   Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 29–41 : Autor(es): Ashford, J., G. Duhamel, C. Jones and S. Bobko

9. Age estimation and maturity of the ridge-scaled macrourid (Macrourus whitsoni) from the Ross Sea

   mean total length-at-maturity (38.8 and 46.4 cm) and mean age-at-maturity (10.6 and 13.6 years) are ... Paper Title:  Age estimation and maturity of the ridge-scaled macrourid (Macrourus whitsoni) from ... -sex were fitted separately to a revised length-at-age dataset and compared using the likelihood-ratio ... test. Von Bertalanffy parameters for the pooled dataset with unsexed juveniles are L ∞ 76.12, K 0.065 ... cm) and mean age-at-maturity (10.6 and 13.6 years) are presented for males and females respectively ... standard normal distribution R es id ua ls (b) 20 30 40 50 60 70 80 -2 -1 0 1 2 Fitted values R ... 0 1 2 3 20 30 40 50 60 70 80 Fitted ... R es id ua ls (b) 20 30 40 50 60 70 80 -2 -1 0 1 2 Fitted values R es id ua ls -3 -2 -1 ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 291–303 : Autor(es): Marriott, P.M., M.J. Manning and P.L. Horn

10. Comparison of age readings from scales and otoliths of the Patagonian toothfish (Dissostichus eleginoides) from South Georgia

    test for paired data (Ts = 0.256, n = 59) conducted on the remaining 56% showed that differences in age ... appropriate for determining the age of D. eleginoides because it does not underestimate age and is the most ... 24 years. This is very close to the maximum age of 22.8 years calculated from Taylor's formulae ... Paper Title:  Comparison of age readings from scales and otoliths of the Patagonian toothfish ... 18. Cassia 0 8 8 8 8 8 8 8 m w m 2 z ? & 80 T Age 5 " @ ! \ ! , L L 20 t 0 0 0 0 ... m 2 z z : 80 20 0 -Uo 0 0 0 0 0 0 0 m w m 2 z z z Age l 7 o J s ! : > ! ! ! 0 0 ... represents one year of life. Counting such annuli is a valid technique for determining the age of Antarctic ... 7600 Mar del Plata, Argentina Abstract Scale and otolith age readings were compared for 105 ...

    Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 191–203 : Autor(es): Cassia, M.C

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