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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

   selectivity functions. 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Immature selectivity Age (y ... Age (y) 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Mature selectivity Age (y) 2000 2010 ... both selectivity functions, changes in Lmean and L75 from one year to the next cor- rectly predict ... missing larger fish can be obtained with two different selectivity functions: one that catches large ...

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

2. Archival and satellite-linked data recorders

   recorders are deployed on freely swimming animals and gather data on aspects of an animal’'s diving ... behaviour. The records can be recovered in one of two ways: the data recorder must either be recovered ... equivalents of these two types of recorders have become available. A raw-data recorder is one in which the ... transmissions in one satellite pass before a geolocation can be determined. This presents no problem for a ... transmissions throughout a pass of the satellite to geolocate reliably. The animal under investigation ... several identification codes so that more than one message can be transmitted per satellite pass. Such ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 475-493 : Auteur(s): Hill, R.D.

3. 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 on ... one genetic stock with gene flow via the Antarctic Circumpolar Current or two or more stocks ... isolated population of D. mawsoni seems very unlikely given the long (almost two years) pelagic stage ... and 2012 that indicated genetic similarity between the two years. This study, which included ... is restricted to the Convention Area man- aged by CCAMLR. The fishery for D. mawsoni started in the ...

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

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

   and 4 animals, and have a relatively lower impact on catches, depressing CPUE by up to 20%. Sperm ... whales have been more frequently encountered in recent years, occurring in larger pod sizes, whereas ... South Georgia Li ne s S P W o bs er ve d (% ) 100 90 80 70 60 50 40 30 20 10 0 May ... °S 36.5°W); (b) the five fine-scale rectangles with the highest CPUE in any one year. The results ... over the years 2003 to 2006, followed by two years of low interaction, and finally another year of ... , followed by two years of low interaction, and finally another year of very high interaction in 20009. The ...

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

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

   was concentrated away from tag concentrations, or overly concentrated in them, the Petersen estimator ... allows simulation of releases by box over multiple years. The model performed as expected with test ... 10 20 30 40 50 60 70 80 90 0 50000 100000 150000 200000 250000 est. population (n) pr oj ... 40 20 0 90 80 70 60 50 40 30 20 10 0 0 50000 100000 150000 200000 250000 ... of toothfish typically move only 20–30 km each year (Marlow et al., 2003). This paper investigates ... correctly capture movement reversals – where an animal moves west one year and back east the next, for ...

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

6. Consideration of major issues in ecosystem monitoring and management

   10000 15000 0 10 20 30 40 50 60 70 80 90 100 Year Po pu la tio n si ze Recruitment fails twice ... 40 50 60 70 80 90 100 Year Po pu la tio n si ze Recruitment fails twice at random each decade ... recruitment is randomly distributed between 1 000 and 2 000. From year 20 onwards for two randomly selected ... rates can 223 Ecosystem monitoring and management 0 20 40 60 80 100 0 2 4 6 8 10 Age at ...

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

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

   continental shelf/slope between 46°-55°S and 60°-64°W, and around South Georgia between 53°-55°30' and 3 ... eleginoides) was investigated in two offshore regions in the southwestern Atlantic: on the Argentinian ... °-45°W. The South 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 ... main line of 20 000 m, with branch lines each with 90 hooks (model 'Ancora', 30 mm gap) spaced at 1 m ... ) with a modal length of around 60 cm TL are Feeding Ecology of Patagonian Toothfish 70-79 80-89 90 ... . Its geographic distribution ranges from 30"s in the Pacific, to the north of Chile, to Cape Horn ... Peninsula. Two biologically distinct populations of this species are recognised, o n e i n t he s o u t ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 105–124 : Auteur(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 ... Islands 0 10 20 30 40 50 60 70 80 90 100 2003/04 2004/05 2005/06 2006/07 2007/08 Fishing ... : Mean interaction rates of killer and sperm whales with longlines between 2003 and 2008. 0 10 20 30 ... 5 10 15 20 25 30 2003/04 2004/05 2005/06 2006/07 2007/08 Fishing season D ep re da tio n ... (49%) depredation had occurred in that year. These two factors could account for the lower estimated ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 179–195 : Auteur(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)

   there are two stocks in the area, one in Division 58.4.1 and one in Division 58.4.2, with the division ... operating off the coast of East Antarctica (30°E–150°E; FAO/CCAMLR Divisions 58.4.1 and 58.4.2) since 2003 ... between them being at about 90°E. The western stock may be centred around Prydz Bay, and appears to be of ... (only five where time at liberty was a year or more). These recaptures were inconsistent with ... 58.4.2. Fishing years extend from 1 December of the previous year to 30 November of the named year ... . Biological data suggest that there are two stocks in the area, one in Division 58.4.1 and one in Division ... ) showed the two methods produced area size estimates that dif- fer by approximately 20% overall (with ... that although two tags are assumed to have been recovered from SSRU 5841Ce, in reality one was ...

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

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

    also possibly due to age-dependent mortality and commercial fishing. File:  14everson.pdf ... year class: To test whether there is a significant difference between the two survivorship ... ) the first fully recruited year class is correctly chosen; (ii) when the data are derived from one ... - E a, f F 0 8 6 -5 -10 -1 5 -20 3 4 5 6 7 8 9 Age (years) Olsen Frolkina Kock ... relatively easily from data on age composition, but it is generally difficult to divide this into its two ...

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

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