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1. Natural mortality rate in the mackerel icefish (Champsocephalus gunnari) around South Georgia

   chosen; (ii) when the data are derived from one year, recruitment is constant; (iii) sampling ... for 2 20 15 10 5 - E a, f F 0 8 6 -5 -10 -1 5 -20 3 4 5 6 7 8 9 Age (years ... on age composition, but it is generally difficult to divide this into its two most important components ... of 0.55) and 0.35 (from SC-CAMLR, 1988) should be used. The following year the information in Frolkina ... South Georgia Abstract / Description:  Information on natural mortality rates of the mackerel icefish ... provide an estimate that is unaffected by confounding effects mainly due to recruitment variation, but ...

   Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 245–257 : Author(s): Everson, I

2. Consideration of major issues in ecosystem monitoring and management

   for bringing these various components together as an ecosystem approach to management is discussed. File ... components together as an ecosystem approach to management is discussed. ... Recruitment normal 50% Survivorship 0 1000 2000 3000 4000 0 10 20 30 40 50 60 70 80 90 100 Year Po pu ... distributed between 1 000 and 2 000. From year 20 onwards for two randomly selected seasons in every 10 ... trip duration 2–3 months Several days 20–100 C2 Pup growth 2–3 months 2–3 months 30–150 Calendar dateP ... . A B C A B C (a) (b) 221 Ecosystem monitoring and management 90% Survivorship 0 5000 10000 15000 0 10 20 30 40 50 60 ...

   Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 213–232 : Author(s): Everson, I

3. Sensitivity investigation of the SDWBA Antarctic krill target strength model to fatness, material contrast and orientation

   . In this study, the SDWBA TS pattern and frequency response behaviours at standard survey frequencies and animal ... and the distribution of animal orientations. Due to the high variability of TS to realistic changes in parameters ... at standard survey frequencies and animal lengths are explored via a sensitivity analysis of some important ... the organism and the surrounding seawater and the distribution of animal orientations. Due to the high ... parameters. One approach is to describe the animal’s body by digitising the main morpho- logical structures ... be achieved by discretising the animal’s body by digitisation of the main morphological struc- tures in two ... 1. 15 0. 29 3 0. 36 2 20 1. 2 0. 31 9 0. 39 4 30 1. 3 0. 37 4 0. 46 2 40 ... deviation (5, 10, 20 and 30 degrees) of the Gaussian distribution of orientation. It is observed ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 97–122 : Author(s): Calise, L. and G. Skaret

4. Chilean krill fishery: analysis of the 1991 season

   ro () 30 ....... 0 Q) 20 O'l ctl -10 c Q) Q 0 "-Q) (L 1977 1979 1981 1983 1985 1987 1989 ... .. --,-----, .. ---'-----------;'t;--'---"??--------"'" ;§ l Year average = 108 J 40 -+-----, 1 5 10 15 20 25 Fishing day (Starting 20/02/91) Figure 2: Total ... 15 20 25 30 35 Fishing day (Starting 20/02/91) Figure 7: Daily average haul depth Cm) during 1991 ... .H--r i+f 111111-, L~~j r 1 TI r I n r o 1 5 10 15 20 25 30 35 Fishing day (Starting 20/02/91) Figure ... paper summarises Chilean catch data for 1991. Special emphasis is given to the analysis of haul-by-haul ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 273–287 : Author(s): Marín, V.H., A. Mujica and P. Eberhard

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

   on the mackerel icefish (Champsocephalus gunnari) have been simulated for a period of 30 years. These were ... ) have been simulated for a period of 30 years. These were: different levels of constant fishing ... with F increasing three or five years after a good recruitment; pulse fishing at an interval of three years ... to the strength of the incoming year class. An increase of F, however, should not occur earlier than four years ...

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

6. Is current management of the Antarctic krill fishery in the Atlantic sector of the Southern Ocean precautionary?

   estimated subarea biomass in up to 20% of years due to high variability in krill biomass indices. The actual ... in up to 20% of years due to high variability in krill biomass indices. The actual exploitation rate ... in 1991, is 0.62 million tonnes year –1, equivalent to ~1% of the regional biomass estimated in 2000. Each ... subarea has also had its own catch limit, between 0.093 and 0.279 million tonnes year –1, since 2009 ... exceed 9.3% of conservatively estimated subarea biomass in up to 20% of years due to high variability ... . the total weight of reproductively mature individuals) after 20 years of fishing should not be below 75 ... % of the reference level) and one of the ‘acceptable limits’ on risk (10% probability of falling below 20 ... to simulations, harvesting the trigger level each year for 20 years would reduce the krill stock by 2% (SC ...

   Science Journal Paper : CCAMLR Science, Volume 23 (CCAMLR Science, Volume 23) : 31–51 : Author(s): Hill, S.L., A. Atkinson, C. Darby, S. Fielding, B.A. Krafft, O.R. Godø, G. Skaret, P.N. Trathan and J.L. Watkins

7. Assessment and tag program adaption methods for exploratory fisheries in the CAMLR Convention Area: an example application for Division 58.4.3a

   abundance estimator, is defined whereby catch limits and tagging rates can be adjusted together to define ... tagging levels that will produce an expected abundance estimate in the following year of a given precision ... be adjusted together to define tagging levels that will produce an expected abundance estimate ... in the following year of a given precision whilst ensuring the sustainable exploitation of the stock as per ... % of K (in this case), not its status relative to 20% of K in the final year of projection. One might then expect ... in the following year/season, as required. As mentioned, the Lincoln-Petersen abundance esti- mator (Seber, 1982 ... ) is employed and, from a fish- eries context it relates, in any given year/season, the number of animals ... and Tiao, 1973; Bernardo, 2003) for the carrying capacity, K, is assumed, but (given that only one year ...

   Science Journal Paper : CCAMLR Science, Volume 16 (CCAMLR Science, Volume 16) : 101–113 : Author(s): Hillary, R.M

8. Status of the coastal stocks of Dissostichus spp. in East Antarctica (Divisions 58.4.1 and 58.4.2)

   that there are two stocks in the area, one in Division 58.4.1 and one in Division 58.4.2, with the division between ... operating off the coast of East Antarctica (30°E–150°E; FAO/CCAMLR Divisions 58.4.1 and 58.4.2) since 2003 ... with the Ross Sea, where an analytical assessment has been possible for several years, and through analysis ... where time at liberty was a year or more). These recaptures were inconsistent with expectations given ... suggest that there are two stocks in the area, one in Division 58.4.1 and one in Division 58.4.2 ... in Divisions 58.4.1 and 58.4.2. Fishing years extend from 1 December of the previous year to 30 November ... that although two tags are assumed to have been recovered from SSRU 5841Ce, in reality one was recovered ... areas. There is apparent localisation of the fishing so it could also be the case that, from one year ...

   Science Journal Paper : CCAMLR Science, Volume 16 (CCAMLR Science, Volume 16) : 71–100 : Author(s): Agnew, D.J., C. Edwards, R. Hillary, R. Mitchell and L.J. López Abellán

9. Selectivity of commercial and research trawls in relation to krill

   more large krill (35-58 mm) than catches of the research trawl (30-54 mm). The maximum difference ... research trawl. The two types of trawl have different catchability characteristics: the research trawl ... large krill (35-58 mm) than catches of the research trawl (30-54 mm). The maximum difference in mean ... research trawl. The two types of trawl have different catchability characteristics: the research trawl ... is one which needs to be investigated. During recent years one of the main methods of estimating ... the commercial and research trawls. From this, one may conclude that samples were taken from two separate ... -58 mm) than catches of the research trawl (30-54 mm). The maximum difference in mean length ... the commercial RT 72/308 trawl are more accurate than those obtained using the IKMT research trawl. The two ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 161–169 : Author(s): Kasatkina, S.M

10. Marine mammals and demersal longline fishery interactions in Crozet and Kerguelen Exclusive Economic Zones: an assessment of depredation levels

    whales. These two species, alone or in co-occurrence with each other, were observed in 71% of the 1 308 ... . These two species, alone or in co-occurrence with each other, were observed in 54% of the 6 262 longlines ... % in the presence of killer whales, 12.1% by sperm whales, and 42.5% when both species were present together ... whales and sperm whales. These two species, alone or in co-occurrence with each other, were observed ... (n = 552, range 1–20) and 4.1 ± 3.4 (n = 737, range 1–30) individuals respectively. Table 1: Number ... in the Crozet EEZ per fi shing sector and marine mammal species. 0% 10% 20% 30% 40% 50% 60% 70% 80% 90 ... % 50% 40% 30% 20% 10% 0% 11 12 13 14 ... tonnes depredated from the longlines by killer whales and sperm whales) over the two-year study period ...

    Science Journal Paper : CCAMLR Science, Volume 14 (CCAMLR Science, Volume 14) : 67–82 : Author(s): Roche, C., C. Guinet, N. Gasco and G. Duhamel

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