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1. Length-based assessments revisited – why stock status and fishing mortality of long-lived species such as toothfish cannot be inferred from length-frequency data alone

   development. The failure of the tag-recapture program to provide robust assessments in many areas and doubts ... / Description:  In many of CCAMLR’s new and exploratory fisheries, stock assessment techniques are still in ... and fishing mortality from length-frequency data alone. In this paper, a number of length-based stock ... Paper Title:  Length-based assessments revisited – why stock status and fishing mortality of long ... : mean mean c L LZ K L L ¥ -= - (2) where only the mean length Lmean in a sample of fish above ... assessment techniques are still in development. The failure of the tag-recapture program to provide robust ... required for a standardisa- tion of catch rates and estimation of relative abun- dance. In addition, the ... effects of spatial variability in stock distribution and the non-random behaviour of fishing vessels are ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 57–73 : Autor(es): Ziegler, P.E., D.C. Welsford and A.J. Constable

2. 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 ... ). The Commission for the Conservation of Antarctic Marine Living Resources has adopted a set of ... 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 ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II) : 19-52 : Autor(es): McKenna, Jr., J.E. and S.B. Saila

3. 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 ... the Conservation of Antarctic Marine Living Resources is concerned with conserving the Antarctic ... 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 ...

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

4. INVESTIGATING LENGTH AT MATURITY OF ANTARCTIC TOOTHFISH (DISSOSTICHUS MAWSONI) BASED ON SCIENTIFIC OBSERVERS’ DATA

   Abstract:  Through generalised linear models, the gonadosomatic index of Antarctic toothfish in ... difference in the GSI values of fish at different maturity stages. However these studies were carried out on ... 137cm. The equivalent GSI at 50% maturity was in the range of 1.1 to 1.4%. These results were used to ... histology and GSI data, most fish found in the northern areas, about a third of those found in the slope ...

   Meeting Document : WG-FSA-08/48 : Autor(es): S. Mormede, S. Parker and P. Grimes (New Zealand)

5. Multiple acoustic estimates of krill density at South Georgia during 2000/2001 reveal significant intra-annual and spatial variability

   was less than that in the eastern box (80.4 g m-2). Analysis of mid-season western survey box transect ... was intermediate between the eastern and western areas. The size structure of the krill in the central ... density to the south-west of South Georgia was 32.1 g m-2 mid-season. By March, krill density in the ... single “snap-shot” acoustic survey data. This is a crucial step in the elucidation of response functions ...

   Meeting Document : WG-EMM-01/15 : Autor(es): A.S. Brierley, C. Goss, S.A. Grant, J.L. Watkins, K. Reid, M. Belchier, I. Everson, M.J. Jessop, V. Afanasyev and J. Robst (United Kingdom)

6. IMPACTS OF CLIMATE CHANGE ON ANTARCTIC MARINE ECOSYSTEMS: A CALL FOR ACTION

   decade, but little in the way of policy or operational change has resulted at CCAMLR. Over the past 50 ... ice. "The uncertainty in climate predictions leads to uncertainty in projections of impacts, but ... Committee needs to increase its work on climate change impacts in order to consider the consequences of a ... approach to management in the context of the unknowns of climate change, and to include in this approach ...

   Meeting Document : CCAMLR-XXVII/BG/27 : Autor(es): Submitted by ASOC

7. 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 : Autor(es): Hewitt, R

8. An index of per capita recruitment

   )eM where R1 is the proportion of age-1 animals sampled in year y and M is the post-recruit mortality ... the population is available; and 4) the proportion of age-1 animals in the sample can be determined ... assumed in order to investigate the resulting distributions of PCR. Distributions of PCR are skewed toward ... conclusions are insensitive to changes in the shape of the functional relationship between spawners and ...

   Meeting Document : WG-EMM-99/50 : Autor(es): R. Hewitt (USA)

9. NET-BASED VERIFICATION OF ACOUSTIC TECHNIQUES USED TO IDENTIFY ANTARCTIC KRILL

   model derived target id window only identified krill in 6 of the 16 nets correctly. The ‘2 freq 2-16 ... ’ algorithm attributed more than 90 % of the total backscatter to krill in all but 1 aggregation with the ‘2 ... krill in 12 out of the 16 nets. The ‘2 freq 2 – 12’ window only attributed more than 90 % of the total ... backscatter to krill in 6 nets while the ‘3 freq model’ attributed only just greater than 50 % of the ...

   Meeting Document : WG-EMM-08/54 : Autor(es): J. Watkins and S. Fielding (United Kingdom)

10. Detailed distribution of krill fishing around South Georgia

    only been available to the scientific community in the form of sub-area or fine-scale(0.5 ° latitude by ... has operated they do not reveal the localised nature of the fishing operation. In particular they give ... available from August but the fishery was restricted in that period to an area on the western edge of the ... Abstract:  The distribution of kri!! harvesting effort and associated catch rates has previously ...

    Meeting Document : WG-EMM-96/64 : Autor(es): Parkes, G., Everson, I., Trathan, P.N., Murphy, E.J.

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