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1. Natural mortality rate in the mackerel icefish (Champsocephalus gunnari) around South Georgia

   , but also possibly due to age-dependent mortality and commercial fishing. File:  14everson.pdf ... that is unaffected by confounding effects mainly due to recruitment variation, but also possibly due to age-dependent ... for 2 20 15 10 5 - E a, f F 0 8 6 -5 -10 -1 5 -20 3 4 5 6 7 8 9 Age (years ... on age composition, but it is generally difficult to divide this into its two most important components ... recruited age classes, and no is the number sampled from the first fully recruited year class: To test ... in Figure 1 and assuming that fish are fully recruited at age 3 years. Using the assumption that fish ...

   Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 245–257 : Author(s): Everson, I

2. Towards an initial operational management procedure for the krill fishery in Subareas 48.1, 48.2 and 48.3

   one particular test of robustness to the assumptions of the operating model, are carried out ... one particular test of robustness to the assumptions of the operating model, are carried out ... of the previous three years' CPUE values fall below a target level of 0.75 CPUE ref. An operating model ... of krill over a 20-year harvesting period from falling below 60% of its average unexploited level; subject ... to these objectives. Since the analysis is stochastic, the statistics change from one 20-year simulation to the next ... appear to be one which attempts to take account of the requirements of Article n in an implicit manner ... one particular test of robustness to the assumptions of the operating model, are carried out ... K .z:.onYIqeHHSIM, c.z:.eJlaHHblM B pa6oqei:t Mo.z:.eJlH, 6blJla BbInOJlHeHa .z:.JlSI Toro, qTo6bl ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 189–219 : Author(s): Butterworth, D.S.

3. Krill distribution in the western Atlantic sector of the Southern Ocean during 1983/84, 1984/85 and 1987/88 based on the results of Soviet mesoscale surveys conducted using an Isaacs-Kidd midwater trawl

   by a change in biomass of more than two orders of magnitude in different seasons, was observed in the South ... -temporal scale of the survey, which is characterised by a change in biomass of more than two orders ... /85 r.). P ~ C C M ~ T ~ M B ~ ~ T C R B03MOXHOCTb nOnOnHeHHX 3anaCOB KPMnX B pafi0He ... in Figures 2 to 4. One feature observed was the permanent existence of extensive zones of high biomass ... , especially if one considers a previous anomaly which was unfavourable for their reproduction in the 1983/84 ... krill stock within Subareas 48.1 to 48.3. Allowing that one of the sources of krill stock ...

   Science Journal Paper : CCAMLR Science, Volume 6 (CCAMLR Science, Volume 6) : 59–70 : Author(s): Sushin, V.A. and K.E. Shulgovsky

4. Diet study of Antarctic toothfish caught in the east Antarctic based on stomach content, fatty acid and stable isotope analyses

   : further evidence and the relation between δ15N and animal age. Geochim. Cosmochim. Acta, 48 (5): 1135 ... cluster analysis on the PCA plots were used to visualise trophic relationships among samples. One-way ... groups (one-way ANOVA, p = 0.403). In contrast, δ15N values of Antarctic toothfish differed among size ... groups, showing that groups A and B had lower δ15N val- ues than groups C and D (one-way ANOVA, Tukey ... Paper Title:  Diet study of Antarctic toothfish caught in the east Antarctic based on stomach ... toothfish stomachs. Stomach content analyses showed that Antarctic toothfish fed primarily on fish and to a ... , indicating a higher trophic position. This is the first study to provide information on the diet of Antarctic ... these methods. Further studies on the trophic relationship between Antarctic toothfish and other species ...

   Science Journal Paper : CCAMLR Science, Volume 22 (CCAMLR Science, Volume 22) : 29–44 : Author(s): Park, H.J. , I. Yeon, E. Han, Y.J. Lee, S.M. Hanchet, G.W. Baeck, Y. Kwon, S.G. Choi, D.W. Lee and C.K. Kang*

5. [node:field-journal-volume]:37-51

   ; counts were made of the translucent zones. Age estimates were generated on the as- sumption that one ... Research (NIWA). Two species were found, Macrourus whitsoni and M. holotrachys. A previously aged sample ... - rid otoliths, for subsequent ageing, on two com- mercial longline trips to the Ross Sea (CCAMLR ... opaque and one hyaline zone represent one year’s growth in the otolith. A read- ability value ...

   Science Journal Paper : 37–51

6. Demographic characteristics of the Adélie penguin population on Béchervaise Island after 12 years of study

   after 12 years of study Abstract / Description:  Demographic parameters (age-specific survival rates ... Demographic parameters (age-specific survival rates, fecundity levels and population numbers) were ... in eastern Antarctica after 12 years of monitoring under the CCAMLR Ecosystem Monitoring Program (CEMP ... Demographic characteristics of the Adélie penguin population on Béchervaise Island after 12 years ... and produced at least one egg. The overall proportion of breeding females aged 7+ years was determined from ... probabilities of detection (>90% of penguins that survive to 6 years of age have been resighted by age 4 years ... since Adélie penguins elsewhere have been shown to live up to 20 years of age (Reid, 1968; Ainley et ... in female Adélie penguins fi rst occurs between 3 and 7 years of age and fecundity is known to increase ...

   Science Journal Paper : CCAMLR Science, Volume 10 (CCAMLR Science, Volume 10) : 53–74 : Author(s): Clarke, J., L.M. Emmerson, A. Townsend and K.R. Kerry

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

   to set a two-year total allowable catch (TAC). One issue is the accurate identification of age cohorts ... the given harvest control rule to set a two-year total allowable catch (TAC). One issue is the accurate ... model (GYM) packages, which derives population numbers-at-age and projects these numbers forward under ... identification of age cohorts from the survey data. In this paper a length-based approach is described ... bootstrap-at-length, one can obtain different bio- mass distributions at length–age using the two dif ... instead of moving from one age-class to the next. The basic premise is that, for a given time increment ... these numbers forward under the given harvest control rule to set a two-year total allowable catch (TAC). One ... structure in the recruitment of the population sub-levels – animals of a given length grow from one length ...

   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

8. Krill population biology during the 1991 Chilean Antarctic krill fishery

   size frequency distribution and a larger size range were found, with one mode between 32 and 55 mm TL ... size frequency distribution and a larger size range were found, with one mode between 32 and 55 mm TL ... size from 1.5 to 3 cm). Two subsamples of 100 specimens each were taken from 50 samples and analysed ... . The fishing ground was divided into two areas: Area A, north of the South Shetland Islands; and Area B, north ... , with one mode between 32 and 55 mm TL (mean length 43 mm for females and 46 mm for males), and the other ... , distribution and composition of commercial kriU catches is one of the key aspects of the work of WG-Krill ... Island, a clear bimodal size frequency distribution and a larger size range were found, with one mode ... ' 2.80 40 39 08:30 04.03.91 62°33,5' 61 °22,7' 2.90 35 57 21:05 05.03.91 62°34,8' 61 °27,3' 2.40 40 66 ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 223–235 : Author(s): Mujica R., A., E. Acuña S. and A. Rivera O.

9. A preliminary investigation of the possible effects of rhizocephalan parasitism on the management of the crab fishery around South Georgia

   the main characteristics of the system. An age-based host-parasite model is constructed, incorporating two ... 48.3) since 1992. One of the main effects of the parasite is to render infected animals sterile ... , which has been harvested by a new fishery around South Georgia (Subarea 48.3) since 1992. One ... a population model that captures the main characteristics of the system. An age-based host-parasite model ... of healthy animals. Also recall that there is at least one year (i.e., age class) in which mature animals ... in the previous year. Once a crab is infected it remains infected. Male crabs are harvested at a size/age one ... about the growth pattern of this crab population, and I have therefore used an age-based model. One ... obvious advantage of an age-based model is that the time of transition from one age class to the next ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 175–192 : Author(s): Basson, M

10. Effects of weather and sea-ice on the reproductive performance of the Adélie penguin at Edmonson Point, Ross Sea

    ). However, sea-ice conditions (e.g. late break-out or greater extent) is one of the main factors ... recorded manually. Data were recorded at 10 min intervals and averaged for a one-day period. Wind speed ... -ice edge was about 15 km away during the guard and crèche stages of the penguin breeding ... one month to mid-February. This event certainly had a direct effect on the colonies in the southern ... Paper Title:  Effects of weather and sea-ice on the reproductive performance of the Adélie penguin ... males on the second incubation trip. A high number of chicks died during the post-hatching stage and the ...

    Science Journal Paper : CCAMLR Science, Volume 11 (CCAMLR Science, Volume 11) : 99–109 : Author(s): Olmastroni, S., F. Pezzo, V. Volpi and S. Focardi

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