Résultats de la recherche

1. Patterns and processes in the distribution and dynamics of Antarctic krill

   distribution and dynamics of Antarctic krill population at various spatial and temporal scales. We suggest that ... models of increasing complexity be developed iteratively for variability and patchiness of krill ... abundance. Incremental models should then be compared to statistical descriptions of the observed ... critical processes to be added. An analysis of spatial distribution of krill in the Bransfield Strait area ... scales that apparently cannot be explained by physical processes alone. A second descriptor of spatial ... ). Note that the biomass within swarms may be substantially higher since it appears that most swarms have ... Antarctic krill population at various spatial and temporal scales. We suggest that models of increasing ... complexity be developed iteratively for variability and patchiness of krill abundance. Incremental models ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 281–299 : Auteur(s): Levin, S.A., A. Morin and T.M. Powell

2. Estimating unaccounted fishing mortality in the Ross Sea region and Amundsen Sea (CCAMLR Subareas 88.1 and 88.2) bottom longline fisheries targeting Antarctic toothfish

   . However, fish that are captured by fishing gear that is not subsequently retrieved are generally not ... unaccounted fishing mortality from lost lines in these fisheries is provided. These estimates suggest that on ... average 208 tonnes of Antarctic toothfish mortality may be unaccounted for annually. While the current ... estimates may be improved through the adoption of better data reporting practices, these estimates were ... loss rate within a spatial cell multiplied by the number of sets with positive hook loss in that cell ... be adjusted upwards to account for higher catch rates associ- ated with longer soak times. The L8 ... procedure. However, the 80% hook loss estimate cannot then be applied to all effort of that gear type as ... that would imply that 80% of all sets made in the fishery by that gear type were lost. With such high ...

   Science Journal Paper : CCAMLR Science, Volume 19 (CCAMLR Science, Volume 19) : 17–30 : Auteur(s): Webber, D.N. and S.J. Parker

3. The survivorship of rays discarded from the South Georgia longline fishery

   between 1 500 and 2 000 m. These findings support CCAMLR’s recommendation that skates and rays be cut from ... . There were some suggestions (not statistically significant) that wind speed (i.e. weather conditions ... can also be used to calculate the expected skate mortality within the fishery, based on depth of ... capture. Further survival experiments should be conducted, particularly in shallow waters, where sampling ... only skates that are alive and undamaged are selected, with animals not being deemed fi t for tagging ... would be experienced during the course of the experiment. These tanks were fi tted with a constant ... only one skate at a time would be placed in a tank, with a maximum of eight skates being tanked at ... protective poise, or the tail may be arched upwards similar to that of a scorpion. Skates that survived ...

   Science Journal Paper : CCAMLR Science, Volume 11 (CCAMLR Science, Volume 11) : 155–164 : Auteur(s): Endicott, M. and D.J. Agnew

4. Status of the krill stock around Elephant Island in 1991/92 and 1992/93

   other years appears to be associated with female maturity development and spawning during the early ... austral summers of 1991/92 and 1992/93 are described and compared with information from previous years ... appears to be a recurring and predictable aspect of the krill stocks in the Antarctic Peninsula region ... appeared to be affected by dense salp concentrations during 1992/93 and 1989/90. File:  02loeb-siegel.pdf ... -Krill) contribution by Loeb and Siegel (1992). That data set is now complete and is compared here with ... described and compared with information from previous years. The general distribution of krill length and ... maturity classes conformed to previous descriptions and appears to be a recurring and predictable aspect ... but poor success from 1991/92. Year class success from these and other years appears to be associated ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 7–33 : Auteur(s): Loeb, V. and V. Siegel

5. CPUEs, body length and greenness of Antarctic krill during 1987/88 season in the fishing ground north of Livingston Island

   fished krill concentrations to the extent that a decrease in krill biomass in this area can be detected ... northern waters of Livingston Island in the 1987/88 season. It appears that Japanese trawlers have not ... among trawlers to be an objective indicator at present. File:  17-Endo-and-Ichii.pdf ... that a decrease in krill biomass in this area can be detected from these data. The percentages of ... that a decrease in krill biomass can be detected from CPUE data in the area north of Livingston Island ... 1987/88 season. It appears that Japanese trawlers have not fished krill concentrations to the extent ... "Egui" as an indicator of greenness of krill were too variable among trawlers to be an objective ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/6 (Selected Scientific Papers, SC-CAMLR-SSP/6) : 323–338 : Auteur(s): Endo, Y. and T. Ichii

6. Alternative methods for determining subarea or local area catch limits for krill in Statistical Area 48

   implementing a management scheme immediately. We recognise that other trade-offs may be equally important ... implementation is low. Therefore, we consider the following trade-off to be important: choosing a biologically ... . Alternatives that allocate the 1.5 million tonne limit by evenly dividing the catch among subareas or by using ... historical catches to set limits can be categorised as having a low potential for delaying implementation ... implementing a management scheme immediately. We recognise that other tradeoffs may be equally important ... single year. Then, for the following two years, that subarea would be closed to fishing. For example, if ... problems with data reliability are not significant. This type of allocation scheme would be relatively ... to be associated with conducting periodic predator censuses. Annual or semi-annual predator ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 237–249 : Auteur(s): Watters, G. and R.P. Hewitt

7. Analysis of the diet of Champsocephalus gunnari at South Georgia in late summer from 1994 to 1997, Dr Eduardo L. Holmberg surveys

   and Thysanoessa sp., which are known to be important alternative food in years of krill scarcity, as ... of the main prey items in the diet of C. gunnari, as well as of the proportions of stomachs with ... phenomenon which could be caused by several concurrent factors. The variation of the diet according to the ... of krill in Subarea 48.3 during the period investigated can be defined as low in 1994 (equivalent to ... al., 1994b; 33-45'33, this study) when krill was scarce. This seems to be in disagreement with our ... . gunnari. This could be related to the fact that when krill are abundant they form dense but spatially ... values of 15-20%) that did not spawn at South Georgia in the 1991 summer season, in concurrence with a ... reversed. The consumption of other prey items such as mysids and Thysanoessa sp., which are known to be ...

   Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 103–123 : Auteur(s): Barrera-Oro, E., R. Casaux and E. Marschoff

8. Quantifying vessel performance in the CCAMLR tagging program: spatially and temporally controlled measures of tag-detection rates

   the maximum distance between fishing events compared. The results suggest that the method can be ... and temporal confounding. This paper presents a method that utilised most of the data while also ... 88.2, as well as changes in the performance of some vessels over time. Further investigations show that ... potentially be developed as a more general method for comparing relative performance of spatially and ... performance indices that were low or with very large confidence intervals (very uncertain) be excluded as ... that there may be impor- tant differences between vessels in their respective detection rates of ... event of the case was paired with fishing events from all other vessels that were carried out within a ... fishing events of the case that were matched with at least one control event, the ratio of the scaled ...

   Science Journal Paper : CCAMLR Science, Volume 20 (CCAMLR Science, Volume 20) : 73–80 : Auteur(s): Mormede, S. and A. Dunn

9. Attribtuion of acoustic echoes to squid in the south Atlantic

   order to characterise an acoustic signature that may be used to identify this species of squid ... . Distinctive echoes that did not occur when other, unsuccessful hauls were undertaken, were the only strong ... single depth zone which reduced the potential number of echoes that might otherwise have been attributed ... to the squid that were caught.   File:  15goss-etal.pdf ... acoustic targets that could be attributed to the haul. No other species were caught with the squid which ... while it was under way to be attributed to the squid with a good degree of certainty. These are that ... be used to identify this species of squid. Distinctive echoes that did not occur when other ... Antarctic Survey (BAS) to realise that there must be substantial stocks of squid available within the ...

   Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 259–271 : Auteur(s): Goss, C., P. Rodhouse, J.L. Watkins and A.S. Brierley

10. By-catch of fish in the krill fishery

    results indicate that the by-catch of fish in the commercial krill fishery may be significant in some ... areas of the South Georgia shelf. The problem is thought to be least in open ocean krill fishing. File ... . Recently concern has been expressed that the fishery may be taking a significant by-catch of fish with the ... result that it may be responsible for significant levels of mortality in other harvested species (SC ... was very small, less than would be required by a commercial fishing fleet. Our results suggest that ... taken as by-catch during krill fishing operations from a research vessel. The results indicate that the ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 381–401 : Auteur(s): Everson, I., A. Neyelov and Y.B. Permitin

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