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1. Acoustic data analysis and models of krill spatial distribution

   / Description:  Acoustic data obtained on 4-5 January 1987 aboard the R/V Professor Siedlecki were used in three ... descriptors of krill spatial aggregation: power spectra for krill biomass fluctuations in space, semivariogram ... wavenumber spectrum resembles a white noise at scales of 2-20 km, although at scales smaller than 1 km the ... and plays an important role in supporting animal populations such as whales, seals and penguins as ... from 1 km to 20 km and relatively sharp decline in the variance below 100 m in scale, approaching the ... , which is a measure of cohesiveness in animal aggregation. The most probably frequency distribution of ... (cycles/km) Power spectra for krill at the 2-20 km scale observed in this analysis (line) and by Weber ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 311–329 : Autor(es): Morin, A., A. Okubo and K. Kawasaki

2. Further computations of the consequences of setting the annual krill catch limit to a fixed fraction of the estimate of krill biomass from a survey

   ), as a function of the fraction of the biomass estimate which is set as the catch for a 20-year period ... relate potential krill yield to a pre-exploitation survey estimate of krill biomass. In this paper, the ... fishing mortality, as specified by the Fourth Meeting, results in marked reductions in the probabilities ... , in the interests of brevity, only the results for the 20-year period are reported here. Results ... . Figure 7 shows trends in the average P/B (production/biomass) ratio over the 20-year harvesting period ... effect only after the first ten years, i.e. it is considered first when computing NIla. (vi) In 'year ... -recruit relationship is introduced: once krill spawning biomass drops below 20% of its median level in ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 81–106 : Autor(es): Butterworth, D.S., G.R. Gluckman, R.B. Thomson, S. Chalis, K. Hiramatsu and D.J. Agnew

3. Areal and seasonal extent of sea-ice cover off the northwestern side of the Antarctic Peninsula: 1979 to 1996

   four periods of extensive ice cover during the last 18 years. Variability in seasonal timing, areal ... extent, seasonal duration and persistence of sea-ice over multiple years is apparent and is consistent ... with features described by Stammerjohn and Smith (1996) for ice cover in the Bellingshausen Sea ... . Periods of extensive winter ice cover peaked in 1980, 1986, 1991and 1995 and were foreshadowed by the late ... periodicity of five to eight years in ice cover and note a five-year periodicity apparent in the air ... subsampled area in km2 during the ith year and jth month. RESULTS AND DISCUSSION The Bellingshausen Sea ... ice cover peaked in July-August, a month earlier than the preceding year. The third period peaked in ... Peninsula indicates that there were four periods of extensive ice cover during the last 18 years ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 65–73 : Autor(es): Hewitt, R

4. Age estimation and maturity of the ridge-scaled macrourid (Macrourus whitsoni) from the Ross Sea

   Islands in 2004. Intensive analysis of otoliths from these specimens greatly increased confidence in the ... interpretation of otolith growth zone structure, supporting the otolith interpretation protocol used in previous ... mean total length-at-maturity (38.8 and 46.4 cm) and mean age-at-maturity (10.6 and 13.6 years) are ... work on this species. Von Bertalanffy growth models assuming different growth by sex and by year-within ... and 30 years old in the second reading. Males Females 0 10 20 30 ... bias plots show that most of the perceived error occurs in fish that were between 13 and 30 years old ... from 2002 (Marriott et al., 2003) to test for differences in growth between years within the sexes. A ... standard normal distribution R es id ua ls (b) 20 30 40 50 60 70 80 -2 -1 0 1 2 Fitted values R ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 291–303 : Autor(es): Marriott, P.M., M.J. Manning and P.L. Horn

5. Line weights of constant mass (and sink rates) for Spanish system Patagonian toothfish longline vessels

   with seabirds. The weights typically used are collections of rocks enclosed in netting bags. During ... the option of substituting steel weights for rock weights while remaining in compliance with the sink ... loss by toothed whales) were tested in the experiment. Spanish-system longlines with 8 kg rock weights ... from 0.68 m s –1 (4 kg rocks) to 1.31 m s –1 (8 kg steel) in the shallow depth ranges. Hydrodynamically ... regime arose from Agnew et al. (2000) who showed a reduction in mortality of black-browed albatrosses ... comprise collections of rocks held in bun- dles by netting bags stitched together from trawler net. This ... hook line are tied together to form a continuous line, and weights are tied to the join in the centre ... collections of rocks enclosed in netting bags. During fishing operations the netting bags abrade on the ...

   Science Journal Paper : CCAMLR Science, Volume 15 (CCAMLR Science, Volume 15) : 93–106 : Autor(es): Robertson, G., C.A. Moreno, E. Gutiérrez, S.G. Candy, E.F. Melvin and J.P. Seco Pon

6. An integrated stock assessment for the Patagonian toothfish (Dissostichus eleginoides) for the Heard and McDonald Islands using CASAL

   representative of the main plateau, where juvenile fish are found, but are of relatively low intensity in effort ... compared to the commercial shots. In contrast, the commercial shots are very restricted in space ... , consisting of three main grounds. The model implemented in CASAL is a simple, single-sex, single-area ... population model, but spatial complexity in the fishery was modelled using separate fishing selectivity ... id (s 2) 0 0 0 0 0 0 0 17 6 30 6 38 0 24 1 66 L on gl in e E (f 7 ... ) indicates that fish younger than 5 years have been selected. Catchability, q, estimates are given in Table ... , 2007b, paragraph 4.6(ii)) noted that the CV in year-class strength (YCS – number of annual age-1 ... with M kept fixed at 0.13 year–1 as recommended in SC-CAMLR (2006). The maximum age was set to 35 ...

   Science Journal Paper : CCAMLR Science, Volume 15 (CCAMLR Science, Volume 15) : 1–34 : Autor(es): Candy, S.G and A.J. Constable

7. Age–length composition of mackerel icefish (Champsocephalus gunnari, Perciformes, Notothenioidei, Channichthyidae) from different parts of the South Georgia shelf

   of mature fish in the west is related to the migration of maturing individuals from the eastern and ... the age of 2-3 years. It has been found that, by number, recruits represent the largest part of the ... to live not only in off-bottom, but also in pelagic waters, an earlier age of sexual maturity ... potentially recover quickly from declines in stock size and may become abundant in the area, as has been ... only observed in five out of 20 abundant year classes at South Georgia (1975,1981,1985,1986 and 1988 ... catch per unit effort of 55.6 tonnes/vessel/ day. In 1971 /72 this species, together with ... taken at the rate of 50 to 100 tonnes. In subsequent years, the C. gzllzrzari fishery shifted to the ... Lepidoiiotothen squni71zfions - formed commercial concentrations in the northwest. In later years, C. gtlnizari ...

   Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 133–146 : Autor(es): Frolkina, G.A

8. Movement and growth of tagged Dissostichus eleginoides around South Georgia and Shag Rocks (Subarea 48.3)

   experimental pot fishing in 2000 and 2001, and have been at liberty from one to two years. Four fish were ... Rocks (Subarea 48.3) Abstract / Description:  In 2000 the UK started a Patagonian toothfish ... tagged and recaptured from the same longline vessel in 2002 after up to two months at liberty. The fish ... and there have been no reported recaptures of these fish tagged at South Georgia or elsewhere in the ... released during experimental pot fi shing in 2000 and 2001, and have been at liberty from one to two years ... observers who have been involved in D. eleginoides tagging to date, specifi cally Gui Moreno, Nick Lock ... year (Figure 1). One vessel that left the South Georgia maritime zone continued pot fi shing in ... Cambridge CB3 0ET, United Kingdom Abstract In 2000 the UK started a Patagonian toothfi sh (Dissostichus ...

   Science Journal Paper : CCAMLR Science, Volume 10 (CCAMLR Science, Volume 10) : 101–111 : Autor(es): Marlow, T.R., D.J. Agnew, M.G. Purves and I. Everson

9. New data on spawning, hatching and growth of Champsocephalus gunnari on the shelf of the Kerguelen Islands

   variations in abundance have been observed. During the sampling period the 1988 cohort was dominant on the ... . Only once have spawners been observed in large numbers on the inner shelf: during the winter of 1991/92 ... the inner shelf has enabled a new cohort of fish to be identified each year. However, annual ... outer shelf. The three-year cycle observed previously seems to be related to the maturation stage of ... 1971/72, yielded annual catches up to 30 000 tonnes in the first years of exploitation (Gerasimchuk ... period of one to two years, the bulk of the catches in the fishery, which is based only fish over three ... taken both by bottom trawl (30' duration; 12 to 20 stations, depending on weather and bottom ... - - - ' , ' i " " " ' " " " ' I " " 0 10 20 30 Total length (cm) Figure 2: Quarterly LFDs for C. gunnari ...

   Science Journal Paper : CCAMLR Science, Volume 2 (CCAMLR Science, Volume 2) : 21–34 : Autor(es): Duhamel, G

10. The foraging range of Adélie penguins at Béchervaise Island, Mac. Robertson Land, Antarctica, and its overlap with the krill fishery

    when the sea became ice free to the coast. Concentrations of krill, Euphausia superba, which have in ... . Robertson Land Coast (approximately 150 000 pairs) and any future harvest of krill in the region. The ... in the South Shetland and South Orkney Islands and reflects the distance offshore of krill, one of ... their major food sources. File:  20-Kerry-et-al.pdf ... in those years where ice conditions allow the fishing fleet to operate further south or in poor ... the sea became ice free to the coast. Concentrations of krill, Euphausia superba, which have in the ... . Robertson Land Coast (approximately 150000 pairs) and any future harvest of krill in the region. The ... birds in the South Shetland and South Orkney Islands and reflects the distance offshore of krill, one ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 337–344 : Autor(es): Kerry, K.R., J.R. Clarke and G.D. Else

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