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1. A first step towards modelling the krill–predator dynamics of the Antarctic ecosystem

   population trends without the need for recourse to environmental change hypotheses. A model is developed ... , together with suggested further areas for investigation. Amongst the key inferences of the study are that ... krill, to explain observed trends – crabeater seals seemingly play an important role and constitute a ... particular priority for improved abundance and trend information; (iii) the Atlantic/Indian Ocean sector ... , a slight increasing trend is evident for the year classes from 1990. Direct observations of the age ... – crabeater seals seemingly play an important role and constitute a particular priority for improved ... ). Antarctic blue whales (Balaenoptera musculus) were harvested legally from 1904 for almost 60 years, fin ... of this species declined substantially over the first 20 years of the fishery, from 1970 to 1990 ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 217–277 : Autor(es): Mori, M. and D.S. Butterworth

2. 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

   other informative estimators for stock abundance and productivity, the review and the simulations ... status and fishing mortality for long-lived fish species such as Patagonian toothfish (Dissostichus ... highlight that interpretation of raw length-frequency data and single length-based indicators for stock ... 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 ... selectivity Age (years) Age (years) Age (years) Year Year Year S el ec tiv ity S to ck s ta tu s ... fishery operations for an assessment of the sta- tus and productivity of the fished stocks to estimate ...

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

3. Results of fish stock assessment survey, South Georgia region, November - December 1986

   rossii and Patagonotothen brevicauda guntheri were an order of magnitude lower than observe by Kock in ... than 1984/85, although not by an order of magnitude. Abundances of Notothenia gibberifrons and ... /85 year classes. Coefficients of variation ranged from 67.9% (Notothenia squamifrons) to 12.6% (C ... I ¥ i \ (, Y I Y I \ i i { I \ i I ( I' i I i I I I I I o 10 20 30 40 50 60 70 80 90 100 LENGTH ... ' L \ i j i I , I o 10 20 30 40 50 60 70 80 LENGTH, CM 90 100 110 120 130 Figure 13. Length ... late 1970's in the South Georgia region has been documented for several years (e.g., Kock et al ... trawl equipped with 80 mm mesh and a 20 mm liner. Distance between wing nets averaged 20.6 m, and ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 143-183 : Autor(es): Gabriel, W.L.

4. Mesopelagic fish of the Southern Ocean - summary results of recent Soviet studies

   data are available on their feeding, reproduction and age/length composition. The paper summarizes ... recently published results of these studies. A general description of mesopelagic myctophids is followed by ... and age/length composition. The paper summarizes recently published results of these studies. A ... mesopelagic fish in Antarctic waters published in the last 5 to 7 years. The paper deals specifically with ... assessment should thus be attempted for each species separately. As mentioned above, spawning and feeding of ... the ACC waters which have an adequate supply of food both for young and adult fish throughout the ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 433–457 : Autor(es): Sabourenkov, E.N.

5. Identifying taxonomic groups vulnerable to bottom longline fishing gear in the Ross Sea region

   the fishery being assessed. New Zealand identified an interim list of taxa to monitor in fishery by ... -catch in the Ross Sea as part of its benthic fisheries impact assessment. The rationale for including or ... : (L = <10 years; M = 10–30 years; H = >30 years) Growth rate: (L = mature <10 years; M = mature 10–20 ... years; H = mature >30 years or evidence for sporadic recruitment events) Fragility: (L = Flexible ... years of age for large speci- mens. Recent dating work indicates that Antarctic sponges of the common ... live longer than the 30 years estimated for more shal- low species (McFadden, 1991; Cordes et al ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 105–127 : Autor(es): Parker, S.J. and D.A. Bowden

6. Distribution of mackerel icefish (Champsocephalus gunnari) (Channichthyidae) around South Georgia at various stages of its life cycle

   into account the spatial–temporal variability of C. gunnari. Young fish of the first age group (<15 ... is h of d om in an t l en gt h 80 m m 90 m m 46 % 29 % 90 m m 10 0 m m ... 30 .5 % 33 % 80 m m 90 m m 10 0 m m 31 % 18 % 26 % 80 m m 90 m m 21 ... (m m ) 80 81 78 76 29 / 5– 7/ 6/ 19 90 L en gt h ra ng e (m m ) 60 –1 20 60 –1 00 ... / 19 86 L en gt h ra ng e (m m ) 60 –1 30 80 –1 30 60 –1 40 70 –1 20 M od al le ng th ...

   Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 49–69 : Autor(es): Frolkina, Zh.A

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

   for the body shape parameterisation can give a high source of uncertainty, and there is an urgent need ... TS of Antarctic krill (Euphausia superba) for use in the acoustic echo-integration method. In this ... study, the SDWBA TS pattern and frequency response behaviours at standard survey frequencies and animal ... the distribution of animal orientations. Due to the high variability of TS to realistic changes in ... rigorously if the scattering as a function of size and frequency for an individual (i.e. target strength ... relationship for the body shape parameterisation can give a high source of uncertainty, and there is an urgent ... used to develop an inversion protocol in a multifrequency context for estimating the mean length and ... values. The last parameter describes the ori- entation of individuals within an aggregation. For a ...

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

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

   captures the main characteristics of the system. An age-based host-parasite model is constructed ... reduce the effective spawning stock biomass, and this clearly has implications for stock management. The ... possible implications of parasitism for management are investigated by considering a population model that ... , incorporating two scenarios for the stock-recruit relationship of the host: (i) resilience; and (ii) sensitivity ... 60 80 100 120 Time (years) Figure 7: Prevalence and spawning stock ratios over time for a ... - recruit relationship was used. 0 20 40 60 80 100 120 Time (years) Figure 8: Prevalence and spawning ... animals only. The sensitive stock- recruit relationship was used. 0 20 40 60 80 100 120 Time (years ... considering a population model that captures the main characteristics of the system. An age-based host ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 175–192 : Autor(es): Basson, M

9. The role of fish as predators of krill (Euphausia superba) and other pelagic resources in the Southern Ocean (submitted to the 2008 Joint CCAMLR-IWC Workshop)

   :  Krill forms an important part of the diet of many Antarctic fish species. An understanding of the role ... when these areas were exploited commercially for Electrona carlsbergi. Currently, the best estimates of ... by mesopelagic fish in the Atlantic sector of the Southern Ocean. It is clear from this review that ... Southern Ocean. Ecosystem models therefore need to account for their role. However, several key areas of ... estimates of fish stocks were available for the split-years (1 July to 30 June) 1975/76 and 1977/78 (Table ... spp.) in the 19th cen- tury and the large baleen whales in the first 80 years of the 20th century ... . Nototheniids and channichthyids have a life span of typically 10–20 years (Kock et al., 1985; La Mesa et al ... pro- vided in Table 4. Non-myctophid species The only other species of mesopelagic fish for which ...

   Science Journal Paper : CCAMLR Science, Volume 19 (CCAMLR Science, Volume 19) : 115–169 : Autor(es): Kock, K.-H., E. Barrera-Oro, M. Belchier, M.A. Collins, G. Duhamel, S. Hanchet, L. Pshenichnov, D. Welsford and R. Williams

10. Distribution of krill (Euphausia superba Dana) catches in the South Shetlands and South Orkneys

    catch in Subarea 48.1 from December to March was taken within 40 km of the coast, and 90% within 80 km ... , foraging ranges and population sizes from the literature are used to show that for some years catches ... South Orkneys Abstract / Description:  A set of concentric zones of 20 km width was defined around ... . Krill catches in these zones are shown to have a consistent pattern in Subarea 48.1 but an unpredictable ... for Subareas 48.1 and 48.2. 100 90 80 .c. 70 J:! tfJ 0 () 50 -0 40 a-e 30 20 10 ... March was taken within 40 km of the coast, and 90% within 80 km in all years 1988 to 1991. In 1987 ... was similar for each of the years examined whereas that for Subarea 48.2 changed each year (Figures 3 ... the literature are used to show that for some years catches within 100 km of predator colonies ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 287–303 : Autor(es): Agnew, D.J.

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