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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

   -frequency data, since a wider range of lengths corresponds to one age than vice versa. This vari- ability ... . 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 ... assumed a single population without movement or migration. It represented age classes from 0 to 50 years ...

   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

2. 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 ... ) and is restricted to the Convention Area man- aged by CCAMLR. The fishery for D. mawsoni started in the late 1990s ... or stock units is unknown and is the subject of scientific debate. There may be one genetic stock ... (age 0+ and 1+), with total length between 41 and 117 mm, are found during spring and summer ... of Antarctic toothfish. Mugue et al. 2 However, one fish was recorded 2 300 km from the release site ...

   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

3. 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 ... that during the 2004/05 season two fish were being taken for every one hauled. This is not taken ... (a ) C or re ct ed ca tc h (t on ne s) , 2- st ag e m od el (b ) 20 03 ... 2), and the number of cetaceans observed (Table 1) it is possible to estimate the aver- age consumption per animal ... and Marion Islands is also open all year but currently only one licensed vessel oper- ates there, this would ...

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

4. Investigation of bias in the mark–recapture estimate of toothfish population size at South Georgia

   away from tag concentrations, or overly concentrated in them, the Petersen estimator either ... tagging and fishing effort were non-ideal, e.g. when fishing effort was concentrated away from tag ... simulation of releases by box over multiple years. The model performed as expected with test situations ... years. The model performed as expected with test situations. It produced a near-perfect estimate ... capture movement reversals – where an animal moves west one year and back east the next, for instance ... released in that and earlier years 40 W 43 3 0' W 48 0 0' W M an ag em en t A re ... S 2 0 0 0 m 1 0 0 0 msh ag W s ha g N W ge or gi a S ge or gi a E ge or gi a 20 03 20 04 Release positions ... of tags released in that and earlier years Fi gu re 1 : D is tr ib ut io n of t ag a nd ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 47–63 : Author(s): Agnew, D.J., G.P. Kirkwood, J. Pearce and J. Clark

5. Consideration of major issues in ecosystem monitoring and management

   and management 0 20 40 60 80 100 0 2 4 6 8 10 Age at first breeding Su rv iv or sh ip (% ) 0.5 ... Chicks 1.0 Chicks 1.5 Chicks 2.0 Chicks 0 20 40 60 80 100 0 2 4 6 8 10 Age at first breeding Su ... shift 7–8 months 25–150 A3 Breeding population size >1 year 100s A4 Age specific survival 1 year 100s ... population size >1 year B2 Breeding success 7 months B3 Age specific survival 1 year Fur seal C1 Foraging ... Ocean resources and highlights the need for information on harvested and dependent species, their ...

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

6. Estimation of natural mortality for the Patagonian toothfish at Heard and McDonald Islands using catch-at-age and aged mark-recapture data from the main trawl ground

   proportions-at-length and fishery- and year-specific age–length keys (ALKs) for years 1998 to 2008. A large ... recapture numbers by age class. Two alternative estimation models were programmed in R, based on alternative ... numbers-at-age. The properties of these two models for estimation of M have been studied using simulation ... obtained using proportions-at-length and fishery- and year-specific age–length keys (ALKs) for years ... ity , S 'a Age (years) ¢ a S 0.05 0.10 0.15 0.20 0.25 0.30 -5 30 0 -5 25 0 -5 20 0 -5 15 ... (years) (a) Age (yrs) P ro po rti on s 0.0 0.1 0.2 0.3 0 5 10 15 20 25 1998 2000 0 5 10 15 20 ... and releases by age class for this fishery were obtained using proportions-at-length and fishery- and year ... -specific age–length keys (ALKs) for years 1998 to 2008. A large proportion of the recaptures of fish ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 29–45 : Author(s): Candy, S.G., D.C. Welsford, T. Lamb, J.J. Verdouw and J.J. Hutchins

7. Comparative feeding ecology of Patagonian toothfish (Dissostichus eleginoides) in the southwestern Atlantic

   between 46°-55°S and 60°-64°W, and around South Georgia between 53°-55°30' and 3°-45°W. The South ... ) was investigated in two offshore regions in the southwestern Atlantic: on the Argentinian continental shelf/slope ... Georgia area was divided into two zones: the shelf zone and deep-water zone. On the Argentinian ... continental shelf/slope, the length of D. eleginoides ranged from 30 to 95 cm total length (TL) which ... ~one6anacb B jJllana3OHe 30-95 CM, YTO COOTBeTCTBYeT CTanHH MOJ'IOAH. B o ~ p y r K ) X H O ~ re0preA ... , ~ o ~ o p b ~ f i nHTaeTcx B OCHOBHOM pbl60fi, H 0 MHOrAa A ~ ~ K o o ~ ~ Z ~ ~ H ~ I M H M rOn ... Georgia deep-water (zone SG2) group revealed three distinct size groups (Figure 4). The first one ... aggregations around South Georgia (Fedoulov et al., 1996). However, in the areas away from the shelf and over ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 105–124 : Author(s): García de la Rosa, S.B., F. Sánchez and D. Figueroa

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

   , killer whales alone, and the two species co-occurring were observed on 32.6%, 18.6% and 23.4 ... whales (Physeter macrocephalus). From 2003 to 2008, sperm whales alone, killer whales alone, and the two ... easily from one vessel to another if the two are operat- ing in close proximity. Thus, while ... as individuals belong- ing to one of the four specialist pods of the Crozet Islands EEZ. This raises a major ... moving more than 40 n miles away. When considering all pods of killer whales in the analysis ... , a fishing vessel travelling more than 40 n miles away could fish on average 3.1 ± 3.0 days before being ...

   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. 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 ... in the area, one in Division 58.4.1 and one in Division 58.4.2, with the division between them being at about ... operating off the coast of East Antarctica (30°E–150°E; FAO/CCAMLR Divisions 58.4.1 and 58.4.2) since 2003 ... them being at about 90°E. The western stock may be centred around Prydz Bay, and appears to be of very ... suggest that there are two stocks in the area, one in Division 58.4.1 and one in Division 58.4.2 ... 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 ... to the next, the fish are tagged in one small area, which is not fished as much in the subsequent 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

10. Species identification and age estimation for the ridge-scaled macrourid (Macrourus whitsoni) from the Ross Sea

    and Atmospheric Research (NIWA). Two species were found, Macrourus whitsoni and M. holotrachys. A previously aged ... Paper Title:  Species identification and age estimation for the ridge-scaled macrourid (Macrourus ... and the geographic source of the aged sample. Counts of translucent zones were made from baked and cross-sectioned ... in the Ross Sea (CCAMLR Subarea 88.1). The zones are assumed to form annually as this ageing methodology has ... ; counts were made of the translucent zones. Age estimates were generated on the as- sumption that one ... Research (NIWA). Two species were found, Macrourus whitsoni and M. holotrachys. A previously aged sample ... - rid otoliths, for subsequent ageing, on two com- mercial longline trips to the Ross Sea (CCAMLR ... opaque and one hyaline zone represent one year’s growth in the otolith. A read- ability value ...

    Science Journal Paper : CCAMLR Science, Volume 10 (CCAMLR Science, Volume 10) : 37–51 : Author(s): Marriott, P., P.L. Horn and P. McMillan

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