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1. Results of fish stock assessment survey, South Georgia, December 1987 - January 1988

   complements earlier surveys in the same area and showed that most of the stocks are continuing to decline ... Paper Title:  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 ... . Notothenia rossii is showing no signs of recovery and Champsocephalus gunnari is likely to continue declining ... tonnes in a season (Kock 1986). The decline in abundance of this species since that time has been ... measures aimed at rebuilding the stocks of N. rossii and maintaining the other fish resources in the ... comparison of estimates of stock biomass and size structure from the research vessel cruise surveys in 1984 ... (1987). Most of the comparisons made here will be in reference to these two surveys. Thirty minute ...

   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

2. Age, growth and mortality of Patagonian toothfish (Dissostichus eleginoides) caught off Kerguelen

   showed discrepancies due to gear-specific catchability, or differences in the available population with ... Paper Title:  Age, growth and mortality of Patagonian toothfish (Dissostichus eleginoides) caught ... off Kerguelen Abstract / Description:  Ages of Patagonian toothfish (Dissostichus eleginoides) caught ... off Kerguelen in 1999 were estimated by reading transverse-sectioned otoliths. Randomly interspersed ... ecosystem while allowing harvesting. In other parts of the world, however, over-harvesting of larger ... Générale et Appliquée of the Museum National d’Histoire Naturelle, in which the age of D. eleginoides ... Kerguelen Methods Observers sampled otoliths of 826 fi sh from the catch taken in March 1999 off ... Kerguelen between depths of 500 and 1 500 m by the longliner FV Northern Pride, and in August/September ...

   Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 29–41 : Auteur(s): Ashford, J., G. Duhamel, C. Jones and S. Bobko

3. An index of per capita recruitment

   recruitment (PCR) is proposed such that where R 1 is the proportion of age-l animals sampled in year y and M ... distributions of R I, and three levels of M were assumed in order to investigate the resulting distributions of ... years, and when all age-l animals spawn. These conclusions are insensitive to changes in the shape of ... in mortality and reduction in the proportion of age-l spawners. Introducing year-to-year random ... the mean of the distribution is near 1. In both = loo and c = age-1 'pawn) the cases, when a was ... where R1 is the proportion of age-l animals sampled in year y and M is the post-recruit mortality rate ... sample of the population is available; and (iv) the proportion of age-l animals in the sample can be ... M were assumed in order to investigate the resulting distributions of PCR. Distributions of PCR ...

   Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 179–196 : Auteur(s): Hewitt, R

4. Distribution of fish larvae at South Georgia: horizontal, vertical, and temporal distribution and early life history relevant to monitoring year-class strength and recruitment

   abundant near the coast, but rare in oceanic waters. During winter in the 265 m deep fiord of Cumberland ... East Bay the early stages of many species were found throughout the water column. In summer only four ... species of larvae were abundant, they were found in the upper 100 m of the water column, especially the ... . The findings are discussed in relation to surveys for sampling the early stages of fish at South ... the early life history stages of Antarctic fish at South Georgia are reported. In winter and summer ... , but rare in oceanic waters. During winter in the 265 m deep fiord of Cumberland East Bay the early ... stages of many species were found throughout the water column. In summer only four species of larvae ... were abundant, they were found in the upper 100 m of the water column, especially the top 2 m layer ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 105-141 : Auteur(s): North, A.W.

5. Acoustic estimates of krill density at South Georgia, 1981 to 1998

   % confidence limits <15 g m-2). For five of the summers between 1990 and 1998 it was possible to calculate ... separate density estimates for northeastern and northwestern South Georgia, and in four of these seasons ... Paper Title:  Acoustic estimates of krill density at South Georgia, 1981 to 1998 Abstract ... / Description:  Acoustic estimates of densities of Antarctic krill, Euphausia superba, at South Georgia during ... presented graphically in Figure 2. Over the period for which data are available, mean density of krill at ... % confidence limits of the mean determined from 10 transects in ~ 9 3 % of cases. For the 1998 box survey to ... (see Priddle et al., 1988). Since Interannual variability in the abundance of t ha t t ime there ... reports of large year-to-year fluctuations in krill has been apparent since the 1920s and 1930s when ...

   Science Journal Paper : CCAMLR Science, Volume 6 (CCAMLR Science, Volume 6) : 47–57 : Auteur(s): Brierley, A.S., J.L. Watkins, C. Goss, M.T. Wilkinson and I. Everson

6. A simulation study of krill fishing by an individual Japanese trawler

   . A major inconsistency is found: haul times are a factor of 4-5 times greater in reality than in the ... abundance indices (generally of a CPUE form) for krill biomass in the 600 n mile square oceanic sector ... modelled are considered, and their performance in response to a variety of ways in which the overall krill ... to be considered to monitor changes in the number, distribution and size of krill concentrations ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 1–108 : Auteur(s): Butterworth, D.S.

7. Reproductive performance of seabirds and seals at South Georgia and Signy Island, South Orkney Islands, 1976-1987: implications for Southern Ocean monitoring studies

   reviewed. Breeding success of the wandering albatross, which breeds in winter and eats fish and squid, has ... fluctuations in reproductive performance of the krill-eating, summer-breeding penguins at Signy Island are not ... in 1980-81 and 1982-83) with the date of ice break-out in late spring. Numerous parameters of ... / Description:  Aspects of the reproductive performance over the last decade of black-browed, grey-headed and ... reduced availability of krill is discussed. The fluctuations in reproductive performance of the krill ... correlate best (especially for Chinstraps, which suffered badly in 1980-81 and 1982-83) with the date of ... reviewed in terms of their sensitivity and suitability for detecting changes in the marine environment ... and P. Rotheryl (United Kingdom) Abstract Aspects of the reproductive performance over the last ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 445-447 : Auteur(s): Croxall, J.P., T.S. McCann, P.A. Prince and P. Rothery

8. Improving estimates of Adélie penguin breeding population size: developing factors to adjust one-off population counts for availability bias

   presented for the collection and development of data to adjust counts of Adélie penguins made at any time in ... point one week after the peak in egg laying, consistent with Standard Method A3 of the CCAMLR Ecosystem ... illustrated using data collected at the Béchervaise Island CEMP site in 2007/08. Estimates of the breeding ... methods such as mark-recapture of individually tagged birds. Given the paucity of adjustment data in the ... at any time in the breeding season to an estimate of the breeding population. The development of ... reference point one week after the peak in egg laying, consistent with Standard Method A3 of the CCAMLR ... method is illustrated using data collected at the Béchervaise Island CEMP site in 2007/08. Estimates of ... paucity of adjustment data in the literature, further collection of availability adjustment data across ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 229–241 : Auteur(s): Southwell, C., J. McKinlay, L. Emmerson, R. Trebilco and K. Newbery

9. Movement and growth of tagged Dissostichus eleginoides around South Georgia and Shag Rocks (Subarea 48.3)

   and there have been no reported recaptures of these fish tagged at South Georgia or elsewhere in the ... Rocks (Subarea 48.3) Abstract / Description:  In 2000 the UK started a Patagonian toothfish ... (Dissostichus eleginoides) tagging program to investigate the spatial and temporal movement of fish and to ... there is greatest fishing activity. Most of the fish recaptured to date were tagged and released during ... Assessment Group (MRAG) Ltd in London. To increase the likelihood of recaptured tags being reported and to ... minimise the potential for non-reporting of recaptured tags, posters, in English and Spanish ... -scale of this process. Tagging in the experimental and commercial fi sheries around South Georgia ... a concen- tration of 100 mg Sr/kg fi sh. The needle was in- serted beneath the scales 1–2 cm below ...

   Science Journal Paper : CCAMLR Science, Volume 10 (CCAMLR Science, Volume 10) : 101–111 : Auteur(s): Marlow, T.R., D.J. Agnew, M.G. Purves and I. Everson

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

    instruments Abstract / Description:  The limited capabilities of existing hydroacoustic instruments in ... in areas surveyed. The task of detecting surface concentrations of krill can be solved with the help ... capable of registering individual krill at a depth of 50–60 m while the vessel is in motion. According to ... expense of a rise in the acoustic power of emission. File:  06-Yudanov.pdf ... ) of shrimp calculated in relation to a mean length of 4.5 cm. As can be seen from the graph, the ... concentrations of krill lead to considerable underestimates of krill biomass in areas surveyed. The task of ... individual krill at a depth of 50 - 60 m while the vessel is in motion. According to theoretical ... a rise in the acoustic power of emission. * * * * * * * * * * DETECTION ET EVALUATION ...

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

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