Résultats de la recherche
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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 ... showed discrepancies due to gear-specific catchability, or differences in the available population with ... partially funded by the United States National Science Foundation under grant No. NSF-OPP- 0231919. They ... , growth and mortality of At- lan tic croaker, Micropogonias undulatus, in the Chesapeake Bay region, with ... for the age data was estimated to be –0.6 years and residual variance 2.9. Age distributions of ... in the available population with depth or season. Age–length keys were constructed for use in ...
Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 29–41 : Auteur(s): Ashford, J., G. Duhamel, C. Jones and S. Bobko
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Food consumption by predators in a CCAMLR integrated study region
/ Description: A detailed description of the structure and mode of operation of a model for estimating food ... consumption of seabird predators is provided. This model is a development of earlier ones used in the South ... provided, illustrating the changes produced by using these new sub-models. Results of initial sensitivity ... analyses indicate particular sensitivity to estimation of metabolic energy requirements. The system is ... ). If periods ashore, when the animals are fasting, were regarded as involving no food consumption, the ... detailed description of the structure and mode of operation of a model for estimating food consumption of ... seabird predators is provided. This model is a development of earlier ones used in the South Georgia ... provided, illustrating the changes produced by using these new sub-models. Results of initial sensitivity ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 489–519 : Auteur(s): Croxall, J.P., C. Ricketts and A.G. Wood
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Results of fish stock assessment survey, South Georgia region, November - December 1986
between 29 November and 17 December 1986 by the R.V. Professor Siedlecki using a Polish B-454 otter trawl ... standard (e.g., relatively little or no gear damage) (Figure 1). In the Shag Rocks region, 13 tows were ... December 1986 by the R.V. Professor Siedlecki using a Polish B-454 otter trawl. Biomass was estimated ... parecieron ser menores en 1986/87 que aquel1as de 1984/85, aunque no en un orden de magnitud. Las ... abundancias de Notothenia qibbertfrons y Chaenocephalus aceratus, tanto las estimadas en este estudio, como ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 143-183 : Auteur(s): Gabriel, W.L.
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Marine mammals and demersal longline fishery interactions in Crozet and Kerguelen Exclusive Economic Zones: an assessment of depredation levels
toothfish (Dissostichus eleginoides) in the Crozet and Kerguelen Islands Exclusive Economic Zones (EEZs ... ) between 2003 and 2005. In the Crozet EEZ, the reported interactions involved killer whales and sperm ... whales. These two species, alone or in co-occurrence with each other, were observed in 71% of the 1 308 ... longlines set. In the Kerguelen EEZ, the reported interactions involved sperm whales and fur seals. These ... . Initially, no data on the arrival and/or departure time of marine mammals from the line-hauling site were ... for the differ- ent fi shing sectors when no marine mammals were detected interacting with the fi ... shing operations. No signifi cant effect and no discernable trend in CPUE could be detected in the ... mammals were present, fur seals had no signifi - cant negative effect on CPUE. But in three of the cases ...
Science Journal Paper : CCAMLR Science, Volume 14 (CCAMLR Science, Volume 14) : 67–82 : Auteur(s): Roche, C., C. Guinet, N. Gasco and G. Duhamel
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A von Bertalanffy growth model for toothfish at Heard Island fitted to length-at-age data and compared to observed growth from mark–recapture studies
aged. Subsampling of random lengthfrequency (LF) data used to obtain the samples of fish for ageing ... used length-bin sampling involving a fixed sample size per bin. Estimation of the VB parameters used a ... definition of the likelihood function based on variable probability (VP) sampling due to the prespecified ... length-dependent selectivity function for trawl fishing and the additional effect of length-bin sampling ... that the term N/n no longer appears in p’. Note that for the LF data the Nj are observed totals for ... of L∞ calculated for each of the equations (A9) to (A12) given in Appendix 2, was no greater than ... sh that were aged. Subsampling of random length- frequency (LF) data used to obtain the samples of fi ... sh for ageing used length-bin sampling involving a fi xed sample size per bin. Estimation of the VB ...
Science Journal Paper : CCAMLR Science, Volume 14 (CCAMLR Science, Volume 14) : 43–66 : Auteur(s): Candy, S.G., A.J. Constable, T. Lamb and R. Williams
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Scientific observations in CCAMLR fisheries – past, present and future
/ Description: CCAMLR has the primary competency for managing fishing south of the Antarctic Polar Front ... -independent studies are difficult and expensive to conduct. In addition, the size of the Convention Area, its ... remoteness and prevailing inclement weather further complicate matters. Therefore, in addition to the ... standard catch and effort data supplied by vessels, the collection of data by scientifically qualified ... reviewing the application of the scheme, CCAMLR is able to identify data which no longer need be collected ... , Australia Email – eugene@ccamlr.org Abstract CCAMLR has the primary competency for managing fi shing ... south of the Antarctic Polar Front. Despite a relatively long history of scientifi c research and fi ... addition, the size of the Convention Area, its remoteness and prevailing inclement weather further ...
Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 81–98 : Auteur(s): Sabourenkov, E.N. and E. Appleyard
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Distribution of mackerel icefish (Champsocephalus gunnari) (Channichthyidae) around South Georgia at various stages of its life cycle
South Georgia at various stages of its life cycle Abstract / Description: The distribution of mackerel ... into account the spatial–temporal variability of C. gunnari. Young fish of the first age group (<15 ... cm in length) were mainly found in the southern part of the study area, immature fish (15–25 cm) in ... the east and southwest, and adults (25–39 cm) in the north. The distribution of C. gunnari changes ... the shelf (Frolkina et al., 1998) (Table 1). In the Shag Rocks area no fi sh smaller than 12 cm ... , while in the Shag Rocks and Black Rocks areas no pre-spawning and spawning fi sh were observed. This ... concentrations were available over the entire shelf, fi sh aggregations were stable and no long migrations were ... were caught in the northeast area. There were no fi sh smaller or 59 Distribution of mackerel ...
Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 49–69 : Auteur(s): Frolkina, Zh.A
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Results of fish stock assessment survey, South Georgia, December 1987 - January 1988
Abstract / Description: Commercial fish stocks around South Georgia have been declining since the early ... complements earlier surveys in the same area and showed that most of the stocks are continuing to decline ... . Notothenia rossii is showing no signs of recovery and Champsocephalus gunnari is likely to continue declining ... hundred and four occurred along the South Georgia coast and were considered standard (e.g. little or no ... (Figure 3a). The first and second modes were present in both 1986/87 and 1987/88, but no discernable mode ... uncommon in the 1987/88 survey, but accounted for the single largest catch (12 mT) at a non-random site ... size class during 1986/87. This size class was absent from the 1987/88 population and no fish over 40 ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II) : 19-52 : Auteur(s): McKenna, Jr., J.E. and S.B. Saila
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Length-at-age in juvenile Patagonian toothfish (Dissostichus eleginoides)
. No difference was found between predicted and estimated ages. We conclude that the two dominant modes ... / Description: We used the otoliths from a sample of Dissostichus eleginoides pre-recruits, whose length ... the length modes observed. Length densities by age were compared graphically with the overall length ... estimated from reading otoliths in a goodness-of-fit test. The majority of the otoliths (83.6%) were ... ned as 1+ year old. As in previous years, apart from the dates of the groundfi sh survey, no ... compared with ages estimated from reading otoliths to test the null hypothesis that there was no ... interpreted as corresponding to the initiation of faster growth during late 1999/ 2000. No bias was ... . The goodness-of-fi t test included n = 232 fi sh of TL 23–46 cm; no difference was found between ...
Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 1–10 : Auteur(s): Ashford, J., C. Jones, S. Bobko and I. Everson
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Size at sexual maturity of Patagonian toothfish (Dissostichus eleginoides)
allowing for this bias indicates that L m50 for female fish in 1997 was no different to that for 1996. The ... (Dissostichus eleginoides) caught in the commercial fishery within Subarea 48.3. The results for 1996 indicate ... that L m50 occurs at 78.5 cm total length for male and 98.2 cm for female fish. In 1997 the results for ... male fish were essentially the same. For female fish there is evidence that in 1997 a significant ... that Lm50 for female fish in 1997 was no different to that for 1996. The implications of this ... is still a dearth of basic information on its ecology. There is still no precise information on the ... was that, due to the closure of the fishery, there were no data for August 1996; this category ... visible to the naked eye, about '1, length of the body cavity. Testis large, white and convoluted, no ...
Science Journal Paper : CCAMLR Science, Volume 6 (CCAMLR Science, Volume 6) : 37–46 : Auteur(s): Everson, I. and A.W. Murray