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1. A composite recruitment index to describe interannual changes in the population structure of Antarctic krill at South Georgia

   target or station net hauls is described. This composite index is compared with an index where density ... net hauls. Therefore, when the number of station net hauls is limited, bias is likely to be reduced if ... target net haul data can be included by using the composite recruitment index. This index is used to ... %), while between 1994 and 1998 the number of 1+ krill found in the population increased with a very ... use such data to calculate recruitment indices requires firstly that the samples can be considered ... obtaining acoustic estimates of krill density that can be used to transform the length-frequency data into ... that contributes to the observed density. This distribution will be referred to as the acoustically ... assumption that is supported by the work of Ricketts et al. (1992). A comparison of these methods with the ...

   Science Journal Paper : CCAMLR Science, Volume 6 (CCAMLR Science, Volume 6) : 71–84 : Autor(es): Watkins, J.L

2. Status of the Polish FIBEX acoustic data from the West Atlantic

   acoustic target strength estimates of krill (SC-CAMLR, 1991a). This analysis indicated that the acoustic ... indicated that spatial variability was important and that parts of the shelf to the north of the South ... variation which has previously been reported for the area and shown to be important. File:  10trathan ... other surveys should be made with caution, particularly where different areas were surveyed, or where ... values from the Profesor Siedlecki survey appear to be consistent with those reported from other FIBEX ... provide abundance estimates that are consistent with other FIBEX cruises, albeit that the Profesor ... interest, it is recommended that these data be archived as part of the BIOMASS database ...

   Science Journal Paper : CCAMLR Science, Volume 6 (CCAMLR Science, Volume 6) : 125–132 : Autor(es): Trathan, P.N., J. Kalinowski and I. Everson

3. Mitigation of seabird captures during hauling in CCAMLR longline fisheries

   / Description:  In recent years there has been an increased focus on reducing seabird captures that occur during ... suggest that there are two key aspects of effective BEDs, firstly that they provide a deterrent to ... seabirds landing adjacent to the line as it is being hauled, and secondly that seabirds are deterred from ... these two key functional characteristics into the specification of a BED to be deployed by longline ... weighting the streamers with objects that would ‘jib’ about in the wind and water, such as stainless steel ... problems with entanglement in the hookline/hauling gear in bad weather but that the heavier weighted ... - cussion with observers and operators, suggests that there are two key aspects of effective BEDs: firstly ... different assemblage of seabird species associ- ated with vessels than in Subarea 48.3, suggest that a Type ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 155–162 : Autor(es): Reid, E., B. Sullivan and J. Clark

4. Southern elephant seals and CCAMLR

   been recently confirmed for the Macquarie Island stock. The availability of food, competition with ... rapidly growing fur seal populations and competition with fishing fleets have all been suggested as ... possible causes of the elephant seal’s decline in the region. Such explanations assume that a communal ... feeding ground, not yet identified, exists and that this exerts some common influence on the species ... (50 000 km2 ) was estimated to be in excess of 230 000 t and with a maximum sustainable yield (MSY ... , cephalopods and euphausiids may be competing with the declining elephant seal population, especially with ... ) of 80 000 t per annum compared with recently suggested standing stock of only 130 000 t and a MSY ... may mingle in winter. Also, it can be hypothesized that large sized - 471 - elephant seals, i.e ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 465-473 : Autor(es): Bester, M.N. and D.G.M. Miller

5. Seal mitigation measures on trawl vessels fishing for krill in CCAMLR Subarea 48.3

   krill fishery around South Georgia, and on mitigation methods that were being developed and deployed to ... avoid fur seal deaths in the fishery. WG-EMM requested that the UK provide further details of the ... mitigation methods that were being developed and deployed to avoid fur seal deaths in the fi shery. WG-EMM ... requested that the UK provide further details of the methods employed for consideration by the ad hoc ... ) in the krill fi shery around South Georgia, and on mitigation methods that were being developed and ... . Mitigation measures Atlantic Navigator The Atlantic Navigator was equipped with a seal- exclusion device ...

   Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 195–205 : Autor(es): Hooper, J., J.M. Clark, C. Charman and D. Agnew

6. Target strengths of krill at 136 and 20 kHz

   . Ensonification of encaged live krill. For aggregations with mean lengths from 45 to 50 mm the mean single-krill ... target strengths range from-68 to-69 dB at 136 kHz. For aggregations with mean lengths from 43 to 47 mm ... . For aggregations with mean lengths from 47 to 50 mm the mean target strengths ranged from-71 to-75 dB ... . At the same frequency for aggregations with mean lengths in the range 41 to 47 mm the mean single ... krill TS carried out by AtlantNIRO from 1980 to 1985. We feel that these may be useful in general ... /intestinal fullness (Figure 8, Table 3). It should be recalled that the nature of dependence between TS and ... aggregations with mean lengths from 45 to 50 mm the mean single-kriU target strengths range from -68 to -69 dB ... at 136 kRz. For aggregations with mean lengths from 43 to 47 mm the mean single-kriU target ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 141–157 : Autor(es): Kasatkina, S.M.

7. Can we satisfactorily estimate variation in krill abundance?

   to year variation in krill abundance it is important that this be quantified and separated from ... of abundance. It is less satisfactory for pelagic fisheries. Evidence is given that CPUE estimated ... ) does not provide a realistic index of krill abundance. Recognising that there is a large natural year ... variation in hill abundance it is important that this be quantified and separated from fishery induced ... abundance. It is less satisfactory for pelagic fisheries. Evidence is given that CPUE estimated from data ... provide a realistic index of krill abundance. Recognising that there is a large natural year to year ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 375-376 : Autor(es): Everson, I.

8. Status of the FIBEX acoustic data from the West Atlantic

   survey) with data collected at 120 kHz (all other vessels), it is concluded that this does not materially ... affect the estimated biomass. The data from the Professor Siedlecki survey do not provide estimates that ... are consistent with the other surveys. The authors can find no explanation for this difference. File ... corrections found at 38 kHz suggests that this method should also be considered with some caution. However ... biomass. The data from the Professor Siedlecki survey do not provide estimates that are consistent with ... time the precautionary catch limit was set, SC-CAMLR also requested that the FIBEX acoustic data be ... the acoustic integration interval adopted by the l t zurn i was different to that used by other ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 35–48 : Autor(es): Trathan, P.N. and I. Everson

9. Effects of different harvesting strategies on the mackerel icefish Champsocephalus gunnari around South Georgia

   50% F 0.1 with F increasing three or five years after a good recruitment; pulse fishing at an ... interval of three years with no fishing in between; and changes in net selectivity resulting in a shift in ... fishing proved to be the least preferable harvesting alternative. In the absence of regular recruit ... surveys constant fishing at F 0.1 is most likely to be the most profitable and least risky harvesting ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/6 (Selected Scientific Papers, SC-CAMLR-SSP/6) : 77–100 : Autor(es): Köster, F.W. and K.-H. Kock

10. Acoustic data analysis and models of krill spatial distribution

    analysis suggest that krill patch size or rather a basic swarm size should be smaller than 200 m, finest ... distribution of krill biomass is bimodal and appears to be the mixture of two log normal distributions. These ... resolution of our data analyzed, and the real spatial distribution of krill should be the manifestation of ... analysis suggest that krill patch size or rather a basic swarm size should be smaller than 200 m, finest ... chlorophyll may be interpreted by the turbulence model with a slight modification by biological activities ... that cannot be explained by the physical process only. However, the power spectra for krill biomass in ... = 115 g/m2). Note that the biomass within swarms may be substantially higher since it appears that most ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 311–329 : Autor(es): Morin, A., A. Okubo and K. Kawasaki

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