Résultats de la recherche

1. Midwater trawl catchability as an aspect of a quantitative assessment of krill biomass conducted using a trawl census survey

   . It could be proven that with two trawls operating in the same area, one could expect the coefficient ... , document, WG-Krill-90/20. SIEGEL, v. 1982. Investigation on Post Spawning Concentration of the Antarctic ... swann depth (metres) 42 29 41 24 29 25 30 21 cr, swann depth 13 20 13 8 10 14 16 8 Mean swann ... 47 59 30 23 20 29 17 cr, mean swann length (metres) 15 16 19 7 10 7 20 4 Swann density field in ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 257–272 : Auteur(s): Kasatkina, S.M.

2. Detection and quantitative estimation of krill concentrations by hydroacoustic instruments

   2.107 L 1----. .1- _______ . __ .... __ . ___ _ 30 35 'ID so Figure 1 60 70 80 90 tDO ·120 ISO ... transmitter frequency. Thus, echo sounders operating at comparatively low frequencies (20-30 kHz) are much ... spread over several miles and can be registered as one or a number of layers at different depths ... . At certain times of the year, krill aggregations stay close to the surface during daylight hours ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 123-139 : Auteur(s): Yudanov, K.I.

3. A post-processing method to remove interference noise from acoustic data collected from Antarctic krill fishing vessels

   –60 –40 –20 Sv (dB) 0 5 10 15 20 -100 -90 -80 ... -70 -60 -50 Ping number M VB S /d B re 1m b –50 –60 –70 –80 –90 –100 M V B S (d B ... ‐80 ‐60 ‐40 ‐20 De pth /m Sv /dB re 1m ‐1 38 kHz 70 kHz 120 kHz krill swarm echoes interference ... noise –120 –100 –80 –60 –40 –20 Sv (dB) 0 50 ...

   Science Journal Paper : CCAMLR Science, Volume 23 (CCAMLR Science, Volume 23) : 17–30 : Auteur(s): Wang, X., J. Zhang and X. Zhao

4. Some comments on the procedure for testing estimators of krill abundance which utilise survey data

   distributions from surveys. ‘Two-level’ models of krill distribution are considered. These achieve overall ... concentrations; these concentrations are then located at random within the survey area. These ‘two-level’ models ... essential difficulty is that the data are collected along one-dimensional transects, whereas it is a two ... distributions from surveys. "Two-level" models of krill distribution are considered. These achieve overall ... concentrations; these concentrations are then located at random within the survey area. These "two-level" models ... density trend. Substitution of a fully random survey design by a systematic one would be a satisfactory ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 191–205 : Auteur(s): Butterworth, D.S., D.L. Borchers and D.G.M. Miller

5. Krill fishing in the Scotia Sea in relation to bathymetry, including the detailed distribution around South Georgia

   results are discussed in relation to the ecology of krill and the fishery's interaction with local ... negligible fishing occurred in the following two seasons. In 1994 the fishery was almost totally based over a ... restricted area of about 30 x 20 km. There were also a few isolated hauls made outside this area. During ... in a CCAMLR reporting quarter of the year on at least one occasion between 1986 and 1992. Based on ... the year on at least one occasion (shaded areas) or on more than one occasion (open squares). The data ... negligible fishing occurred in the following two seasons. In 1994 the fishery was almost totally based over ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 1–17 : Auteur(s): Murphy, E.J., P.N. Trathan, I. Everson, G. Parkes and F.H.J. Daunt

6. Population genetic structure of Patagonian toothfish in the West Indian Ocean sector of the Southern Ocean

   Marion (n = 2) Islands were typed using two fragments of mitochondrial DNA (mtDNA) and seven nuclear ... using two fragments of mitochondrial DNA (mtDNA) and seven nuclear microsatellite loci. MtDNA haplotype ... les groupes géographiques (ADNmt φCT = –0,003; microsatellite φCT = 0,004), ce qui met en évidence ... . eleginoides (albeit rarely) are capable of wide movements across deep waters from one fi shery to another ... are contigu- ous with water no deeper than 600 m separating the two areas (Williams et al., 2002). In ...

   Science Journal Paper : CCAMLR Science, Volume 11 (CCAMLR Science, Volume 11) : 21–32 : Auteur(s): Appleyard, S.A., R. Williams and R.D. Ward

7. The utilization of seabird censuses for krill monitoring

   sample the same spot under the same conditions in two consecutive years. Moreover, other parameters ... are considered. These two representations of the set of observations are reduced in dimensions by ... , but to obtain a picture of the directions where the differences occur. Two applications of the ... is also highly sensitive to non-normally distributed variables and not defined if one or more of ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 393-425 : Auteur(s): Marschoff, E.R., J.G. Visbeek and L.R. Fontana

8. Towards the development of a management plan for mackerel icefish (Champsocephalus gunnari) in Subarea 48.3

   existing CCAMLR decision rules, would preclude the fishery's ever opening. Several possible ... years of poor krill availability. Thus natural  ortality of C. gunnari may, in some years, increase by a ... -year projection period, in only one-third of these was the spawning stock level less than 20% of the ... the time the stock is only depleted for one or two years. This behaviour is a direct result of the ... : Probability of stock biomass dropping below 20% of the unexploited median level over a 10-year period ... years, indicating perhaps that krill scarcity is also variable. The amount of krill present at any one ...

   Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 63–77 : Auteur(s): Agnew, D.J., I. Everson, G.P. Kirkwood and G.B. Parkes

9. Preliminary appraisal of Antarctic fish selection by the 32/36 bottom trawl combined with various codends

   mesh size of 80 mm, currently used on factory trawlers, as well as codends with a structure resembling ... level of up to 80-90%, and a second one, resembling a typical selectivity ogive. Unfortunately, this ... at a 80-90% level clearly ends at this length. with respect to longer fish, the codend material ... ). Both ogives are similar, consisting of two sections: the initial one characterizes the selectivity ... of 23-27 cm at a level as high as 80-90%. It is possible that the body features of Scotia Sea ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 1-48 : Auteur(s): Zaucha, J.

10. Long-term monitoring of krill recruitment and abundance indices in the Elephant Island area (Antarctic Peninsula)

    one- and two-year-old krill (R 1 and R 2 respectively). Statistically significant fluctuations in ... for the Elephant Island area with regard to the representativeness of the study area (60°-62 o 30´S ... and 53 o-57 o 30´W) for proportional recruit and density indices. Proportional recruitment indices ... analysis. Results are compared for one- and two-year-old ]age groups differently. Two-year-old krill consist of medium-sized ... one survey. The Siegel et al. Table 3: Results for RI and R2 for different krill year classes ... two juvenile stocks and therefore data from south of 62'30's are not included in the calculation of ...

    Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 19–35 : Auteur(s): Siegel, V., W. de la Mare and V. Loeb

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