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1. Krill biomass in Area 48 and Area 58: recalculations of FIBEX data

   3S'W 30'W 2S'W 20'W 1S'W r-------------------------~------------~------t_SO'S ...... 00 ... and Proressor Sledleckl MERCATOR PROJECTION .".,. 00 '1" ~ W c::: ~ P=l ;::J rJ) 30'W 2S'W 20 ... ~--~--~--~--~--~----~--~--~--~~ 20 25 30 35 40 45 50 55 60 65 70 Length (mm) Figure 3: Relationship between krill target strength ... WG-KRILL-92/20 KRILL BIOMASS IN AREA 48 AND AREA 58 ... Paper Title:  Krill biomass in Area 48 and Area 58: recalculations of FIBEX data Abstract ... / Description:  FIBEX acoustic and length frequency data held in the BIOMASS database were used to provide ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 157–181 : Author(s): Trathan, P.N., D.J. Agnew, D.G.M. Miller, J.L. Watkins, I. Everson, M.R. Thorley, E. Murphy, A.W.A. Murray and C. Goss

2. Length-based assessment for mackerel icefish (Champsocephalus gunnari) at South Georgia

   the given harvest control rule to set a two-year total allowable catch (TAC). One issue is the accurate ... to set a two-year total allowable catch (TAC). One issue is the accurate identification of age cohorts ... 20 30 40 50 60 Figure 1: Raw icefish density ... survey Length (cm) D en si ty 10 20 30 40 50 10 20 30 40 5010 20 30 40 50 30 20 10 ... 0 30 20 10 0 (a) D en si ty 20 15 10 5 0 2009 survey Length (cm) 10 20 ... these numbers forward under the given harvest control rule to set a two-year total allowable catch (TAC). One ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 129–137 : Author(s): Hillary, R.M., C.T.T. Edwards, R.E. Mitchell and D.J. Agnew

3. A preliminary investigation of the possible effects of rhizocephalan parasitism on the management of the crab fishery around South Georgia

   of the main effects of the parasite is to render infected animals sterile. Parasitism can therefore reduce ... in spawning stock. The effects of harvesting both healthy and infected animals are contrasted with the effects ... of harvesting healthy animals only. Equilibrium and transition dynamics of the models are explored for ranges ... of parameter values. Results indicate a need to harvest or remove infected animals from the population ... of infected animals in the previous time-period. The time lag allows a year for newly-infected hosts ... of infected hosts in the same year rather than the previous year, but excluding newly-infected animals ... by: r = 1 (resilient) and r = 0.01 (sensitive). In each year the number of newly-infected animals in each ... harvesting. 0 0 10 20 30 40 50 60 70 O h Prevalence I resilient S-R (r=10) V sensitive S-R (r=0.01 ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 175–192 : Author(s): Basson, M

4. Estimating the impact of depredation by killer whales and sperm whales on longline fishing for toothfish (Dissostichus eleginoides) around South Georgia

   1 and 4 animals, and have a relatively lower impact on catches, depressing CPUE by up to 20%. Sperm whales have ... to 20%. Sperm whales have been more frequently encountered in recent years, occurring in larger pod ... on 3.8% and sperm whales on 17.7% of lines. Killer whales appear in pod sizes normally of 4 to 10 animals ... been more frequently encountered in recent years, occurring in larger pod sizes, whereas killer whale ... of animals. This was undertaken for each of the years 2003 to 2009; the proportionate decline in CPUE ... 9 4 67 1 4 67 1 20 05 3. 4% 5. 1% 8. 1% 3 05 7 3 16 0 3 21 3 3 30 3 20 ... 1 4. 8 20 .3 0. 31 0. 48 20 06 30 56 1 23 9 36 3 67 0 1 09 6 5. 1 23 ... .3 0. 40 0. 65 20 07 14 68 1 62 6 26 1 75 5 58 2 4. 2 14 .0 0. 38 0. 30 ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 163–178 : Author(s): Moir Clark, J. and D.J. Agnew

5. Comparison of age readings from scales and otoliths of the Patagonian toothfish (Dissostichus eleginoides) from South Georgia

   years. This is very close to the maximum age of 22.8 years calculated from Taylor's formulae which ... . The maximum age of D. eleginoides was found to be 24 years. This is very close to the maximum age of 22.8 ... years calculated from Taylor's formulae which relates maximum observed age to natural mortality ... 640.58 10 317.30 10 461.83 9 326.20 Scales and otoliths from the same individual of D. eleginoides ... among the fish examined was 24 years. DISCUSSION AND CONCLUSIONS Young et al. (1995), who compared ... L, = 207.01 cm, K = +0.0748 and to = -0.2898. The maximum age of D. eleginoides was found to be 24 years ... . This is very close to the maximum age of 22.8 years calculated from Taylor's formulae which relates maximum ...

   Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 191–203 : Author(s): Cassia, M.C

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

   from year to year over that time, ranging from ≈ 2 to  ≈ 150 g m-2 (fresh mass). The 1982, 1991 ... year to year over that time, ranging from ≈2 to ≈150 g m-2(fresh mass). The 1982, 1991 ... Georgia. CONCLUSION Acoustic surveys at South Georgia over the past 20 years suggest that krill ... widely from year to year over that time, ranging from =2 to =l50 g m-2 (fresh mass). The 1982, 1991 ... M ~ c c ~ ) . A~c~paJIb~b1e JIeTHMe IIepHOAbl 1982, 1991 M 1994 rr . XapaKTepH30BanHCb O C ~ ~ ~ H H O HM3KHMH ... Antarctic krill, Etipha~~sia stlperba, at South Georgia reports of large year-to-year fluctuations in krill ...

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

7. A stock assessment model of Antarctic toothfish (Dissostichus mawsoni) in the Ross Sea Region incorporating multi-year mark-recapture data

   Sea Region incorporating multi-year mark-recapture data Abstract / Description:  An exploratory ... , and hence a multi-year mark-recapture tagging program was initiated by New Zealand fishing vessels in 2001 ... was developed for Antarctic toothfish in the Ross Sea region that incorporates multi-year release of tagged fish ... and subsequent multi-year data of recapture of tagged fish in conjunction with fishery catch-at-age data ... . _______________________________________________________________ 1 The CCAMLR fishing season starts on 1 December and ends on 30 November in the following year. In the Ross ... years. This was based on work by Hanchet et al. (2008), who hypothesised an ontogenetic move- ment ... selectivity 10 20 30 40 50 Age Age Age Age Age Age 10 ... 20 30 40 50 10 20 30 40 ...

   Science Journal Paper : CCAMLR Science, Volume 21 (CCAMLR Science, Volume 21) : 39–62 : Author(s): Mormede, S., A. Dunn and S.M. Hanchet

8. 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 ... to simulations, harvesting the trigger level each year for 20 years would reduce the krill stock by 2% (SC ... in noisy time-series such as these. Multi- decadal series (30 to 40 years of data) (Henson et al., 2010 ...

   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

9. Low genetic diversity and temporal stability in the Antarctic toothfish (Dissostichus mawsoni) from near-continental seas of Antarctica

   locations, or between samples collected in consecutive years, were observed. These results, based ... between geographic locations, or between samples collected in consecutive years, were observed ... ; Piyanova et al., 2008; Petrov and Istomin, 2008), who proposed that D. mawsoni can be divided into three ... to the bottom, become benthic and spend a few years on the continen- tal shelf at depths of 50–300 m (Roshchin ... samples collected in consecutive years, were observed. These results, based on analysis of the most ... (almost two years) pelagic stage before fish became benthic, the strong homogenising effect ...

   Science Journal Paper : CCAMLR Science, Volume 21 (CCAMLR Science, Volume 21) : 1–9 : Author(s): Mugue, N.S., A.F. Petrov, D.A. Zelenina, I.I. Gordeev and A.A. Sergeev

10. Estimation of natural mortality using catch-at-age and aged mark-recapture data: a multi-cohort simulation study comparing estimation for a model based on the Baranov equations versus a new mortality equation.

    , M, using multiple cohorts and multiple years of catch-at-age and aged mark-recapture data was tested using ... obtained by integrating an ordinary differential equation (ODE) for within-year population dynamics ... ; constant catch ODE (CCODE) model uses a new total mortality ODE with constant within-year catch per unit ... the process error in predicted catch-at-age numbers. Simulations assumed 1 000 releases per year over 12 years ... , this gave year classes or cohorts (c) of 1 to 46 corresponding to calendar years of 1975 to 2020 for which ... –7.30 CCODE 0.10 LN 0.0993 0.1485 –27.64, 20.58 –0.73 14.87 15.76 BODE 0.13 LNf 0.1266 0.0709 –12.06 ... multiple cohorts and multiple years of catch-at-age and aged mark-recapture data was tested using ... obtained by integrating an ordinary differential equation (ODE) for within-year population dynamics ...

    Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 1–27 : Author(s): Candy, S.G.

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