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1. 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 ... 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 ... 4: The effect of breeding failure and population size. During the fi rst 20 years recruitment is randomly ...

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

2. 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 ...

   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

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 optimal observer coverage in the Antarctic krill fishery

   on board for about 30% of that season. They have achieved a rate of krill sampling equivalent to 18 ... , 20% of total season hauls sampled for krill and an equivalent or higher sampling proportion ... suggest that such strategies should be pursued for at least four years before the Scientific Committee ... on board for about 30% of that season. They have achieved a rate of krill sampling equivalent to 18 ... in the Antarctic krill fishery • a target coverage rate of >50% of vessels each year; • a target of >20 ... in g (% ) A ca m ar 20 02 30 7 A cr ux 20 02 35 4 C hi yo ... 46 3 22 4 13 7 61 56 30 41 12 Fe ol en t 20 05 43 1 43 6 32 6 75 ... 78 76 24 18 A tl an ti c N av ig at or 20 05 30 3 54 40 74 29 ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 139–154 : Author(s): Agnew, D.J., P. Grove, T. Peatman, R. Burn and C.T.T. Edwards

5. 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 ... that: (i) post-recruit mortality does not vary over age or between years; (ii) 100% of age-l animals spawn; (iii ... to recruits per spawner when mortality is constant over all ages and years, and when all age-l animals spawn ... -l animals sampled in year y and M is the post-recruit mortality rate. The intent of the index ... in this time series, first appearing as a large mode at 20 to 30 mm length and in subsequent years ... is the proportion of age-l animals sampled in year y and M is the post-recruit mortality rate. The intent ... or between years; (ii) 100% of age-l animals spawn; (iii) a representative sample of the population ... is constant over all ages and years, and when all age-l animals spawn. These conclusions are insensitive ...

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

6. 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

   . 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Immature selectivity Age (y) Se le ct iv ity ... 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Truncated mature selectivity Age (y) 0 10 20 30 ... 2060 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Year St oc k st at us 2000 2010 2020 2030 2040 2050 2060 ... 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Year 2000 2010 2020 2030 2040 2050 2060 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Year Immature ...

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

7. 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.

8. Interactions of Patagonian toothfish fisheries with killer and sperm whales in the Crozet Islands Exclusive Economic Zone: an assessment of depredation levels and insights on possible mitigation strategies

   on D. eleginoides fisheries at the Crozet Islands 0 10 20 30 40 50 60 70 80 90 100 2003/04 2004/05 2005 ... between 2003 and 2008. 0 10 20 30 40 50 60 70 80 A B C D E F G Fishing vessel In te ra ct io ... is described under ‘Methods’. Tixier et al. 188 –10 –5 0 5 10 15 20 25 30 2003/04 2004/05 2005/06 ... Islands EEZ. The vessels operated all year round with higher activ- ity in February when the fishery ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 179–195 : Author(s): Tixier, P., N. Gasco, G. Duhamel, M. Viviant, M. Authier and C. Guinet

9. A simple approach for calculating the potential yield of krill from biomass survey results

   -exploitation level over a 20 year period of harvesting should equal 10%. The value of, λ depends strongly ... -exploitation level over a 20 year period of harvesting should equal 10%. The value of, λ depends ... for the calculations is that the probability that the krill spawning biomass drops below 20% of its median pre ... for the calculations is that the probability that the krill spawning biomass drops below 20% of its median pre ... to exploitation, over a 20 year period of harvesting, is equal to 10%. Clearly the value of A. is dependent ... upon which to regulate the fishery for the following 20 years, is that from a single pre-exploitation ... 0.2 occurs during the 20 year harvesting period. (x) Repeat steps (ii» to (ix) for different values ... is that the probability that the krill spawning biomass drops below 20% of its median pre-exploitation level over a 20 ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 207–217 : Author(s): Butterworth, D.S., A.E. Punt and M. Basson

10. 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 ...

    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

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