Résultats de la recherche
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Distribution of mackerel icefish (Champsocephalus gunnari) (Channichthyidae) around South Georgia at various stages of its life cycle
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 ... bottom during the day and in the water column at night. Larger fish (>40 cm) did not undertake ... vertical migrations. Variations found in the depth distribution of C. gunnari relate both to fish length ... m. During May, only pre-spawning females of 30–39 cm were caught in the northern and eastern ... about 10%. In the southern and eastern areas, only individual fi sh were found with mature gonads ... observed in the northeastern and eastern areas of the shelf, close to spawning grounds (Shust, 1998 ... . gunnari were observed not only in the eastern and southeastern areas of the shelf but Frolkina 56 T ...
Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 49–69 : Auteur(s): Frolkina, Zh.A
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Estimating the impact of depredation by killer whales and sperm whales on longline fishing for toothfish (Dissostichus eleginoides) around South Georgia
3.8% and sperm whales on 17.7% of lines. Killer whales appear in pod sizes normally of 4 to 10 animals ... toothfish, usually depressing CPUE by about 50%. Sperm whales occur in smaller pod sizes, normally between 1 ... whales have been more frequently encountered in recent years, occurring in larger pod sizes, whereas ... the season in August. Killer whale interactions appear to be more consistent with no obvious pattern ... the cetaceans (by relocating the vessel) and replacing the lost catch. In addition, fishery managers ... . Estimates of food consumption by marine mammals in the Eastern Bering Sea. US Dep. Commer., NOAA Tech ... ), although the pod size appears to be lower in the middle of the fishing sea- son (Figure 1). These ... 17.7% of lines. Killer whales appear in pod sizes normally of 4 to 10 animals, and often appear to ...
Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 163–178 : Auteur(s): Moir Clark, J. and D.J. Agnew
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Age–length composition of mackerel icefish (Champsocephalus gunnari, Perciformes, Notothenioidei, Channichthyidae) from different parts of the South Georgia shelf
of mature fish in the west is related to the migration of maturing individuals from the eastern and ... the eastern, northern, western and southern parts of the shelf, and near Shag Rocks, revealed a ... Rocks. Differences were observed between those those two groups and the eastern group. The larger number ... to live not only in off-bottom, but also in pelagic waters, an earlier age of sexual maturity ... fish in commercial only the eastern part of the shelf war fished, catches was also insignificant ... eastern and was also observed in near-bottom depth strata: northeastern parts of the shelf affected the ... . An analysis of the spatial distribution of C. giirzrznri size and age groups over the eastern ... observed between those t ~ 7 o groups and the easterin group. The larger number of mature fish in the ...
Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 133–146 : Auteur(s): Frolkina, G.A
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A simple approach for calculating the potential yield of krill from biomass survey results
results Abstract / Description: Estimates are calculated for the parameter λ in the yield equation Y = λ ... MB 0 for a krill fishery in which both the fishery and krill growth are seasonal. The criterion used ... -structure has been lost. (iv) In year y = 10 (the year before fishing commences), the a+ biomass is ... estimate Bo which is to be used in equation (1) is considered to be made in the middle of the season (Le ... .3) In the middle of the season during which the krin grow, their mass-at-age (w .) is then: wa ... ** Abstract Estimates are calculated for the parameter 'A, in the yield equation Y = 'A,MB 0 for a kriU ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 207–217 : Auteur(s): Butterworth, D.S., A.E. Punt and M. Basson
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The CCAMLR-2000 Krill Synoptic Survey: a description of the rationale and design
krill which are used in models to estimate sustainable yield in Area 48. The survey design includes two ... large-scale oceanic strata: one in the southwest Atlantic located in the Scotia Sea, and the other to ... these large-scale strata, four mesoscale strata were included in the survey design; these were located ... and the planned cruise tracks for each of the four vessels participating in the survey are shown ... was to improve estimates of the pre- exploitation biomass of krill which are used in models to ... estimate sustainable yield in Area 48. The survey design includes two large-scale oceanic strata: one in ... the southwest Atlantic located in the Scotia Sea, and the other to the north of the Antarctic ... mesoscale strata were included in the survey design; these were located close to the South Sandwich Islands ...
Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 1–23 : Auteur(s): Trathan, P.N., J.L. Watkins, A.W.A. Murray, A.S. Brierley, I. Everson, C. Goss, J. Priddle, K. Reid, P. Ward, R. Hewitt, D. Demer, M. Naganobu, S. Kawaguchi, V. Sushin, S.M. Kasatkina, S. Hedley, S. Kim and T. Pauly
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Analysis of results from demersal fish surveys at South Georgia, undertaken by the United Kingdom and the USSR, January and February 1990
discussions and analyses of the data from a survey from MV Hill Cove in January 1990 and RV Akademik Knipovich ... in February 1990 around South Georgia. Both surveys were characterized by large numbers of small ... increase in the estimated standing stock of Champsocephalus gunnari. The paper describes the ways in which ... these large hauls were considered in the analysis. No ideal method was found for incorporating the large ... finding the proportion of total swept area covered by the highest density in the middle stratum of ... the density of the haul from station 16, and then by the total seabed area in the middle stratum of ... of previous surveys, the greatest proportion being present in the middle (150 to 250 m) depth 236 ... analyses of the data from a survey from MV Hill Cove in January 1990 and RV Akademik Knipovich in ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 223–254 : Auteur(s): (Report of a Joint UK/USSR Workshop, 23 to 27 July 1990)
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Age and growth of Antarctic euphausiacea (crustacea) under natural conditions
Peninsula and the south-eastern Weddell Sea. Life spans range from two years for Euphausia frigida to six ... years for the krill Euphausia superba. Growth in length and weight was calculated by non-linear ... regressions. No difference in growth of krill was observed between the Antarctic Peninsula area and the ... eastern Weddell Sea. Former opinions that differ are discussed. Seasonal growth was re-analyzed for the ... difference in growth of krill was observed between the Antarctic Peninsula area and the eastern Weddell Sea ... south-eastern Weddell Sea. Life spans range from two years for Euphausia frigida to six years for the ... krill Euthausia superba. Growth in length and weight was ca culated by non-linear regressions. No ... generation time of each species is given. In general, Antarctic euphausiids seem to remature and spawn at ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 369-370 : Auteur(s): Siegel, V.
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Analysis of haul data from the South Georgia krill fishery
: Data from individual hauls carried out by vessels operating in the South Georgia krill fishery between ... focused, operating in a limited area along the shelf edge on the northern coast of the island. Each day ... several hauls were undertaken by each vessel (average 7.9 in 1993,9.9 in 1995, and 7.0 in 1996), with ... variability are discussed in relation to previous attempts to model fisheries data and to derive suitable ... out by vessels operating in the South Georgia krill fishery between 1994 and 1996 were examined and a ... emphasise that the krill fishery at South Georgia was geographically focused, operating in a limited area ... each vessel (average 7.9 in 1993,9.9 in 1995, and 7.0 in 1996), with hauls producing higher catch ... discussed in relation to previous attempts to model fisheries data and to derive suitable abundance indices ...
Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 9–30 : Auteur(s): Trathan, P.N., I. Everson, E.J. Murphy and G.B. Parkes
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Preliminary analyses of data collected during experimental phases of the 1994/95 and 1995/96 Antarctic crab fishing seasons
regressions were probably a result of small catches, inter-haul variability in CPUE, and crab movement and ... their release sites. Density estimates from the mark-recapture data were in the order of 50 000 to 100 ... estimates. In general, the experimental harvest regime was successful. The regime provided important ... information about crab distribution and facilitated evaluation of local depletion estimators for use in stock ... different from a simple linear term (p < 0.05). Predictions from equation 3 are illustrated in the middle ... with gamma errors and log-link to the positive CPUE data. The middle panel shows the trend in predicted ... insignificant regressions were probably a result of small catches, inter-haul variability in CPUE, and crab ... movement of crabs away from their release sites. Density estimates from the mark-recapture data were in ...
Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 141–159 : Auteur(s): Watters, G
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Interaction of marine mammals with the longline fishery around the Kerguelen Islands (Division 58.5.1) during the 1995/96 cruise
). These seals are responsible for the loss of 0.75 % of toothfish during the longline sets in which ... interaction occurred, as against 2.2 % of fish lost from the hooks during line hauling. File ... seems to be insignificant (0.75%) in the Kerguelen area, and is lower than the number of fish lost ... 0.75 % of toothfish during the longline sets in which interaction occurred, as against 2.2 % of fish ... lost from the hooks during line hauling. Resume Les interactions observees entre les palangriers ... ). Such interactions can result in damage to fishing gear, a reduction of catch rates and an increase in ...
Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 171–174 : Auteur(s): Capdeville, D