Résultats de la recherche
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Effect of line sink rate on albatross mortality in the Patagonian toothfish longline fishery
Paper Title: Effect of line sink rate on albatross mortality in the Patagonian toothfish longline ... vessels to derive a sink rate and line-weighting regime that would minimise the capture of albatrosses ... based on knowledge of line sink rates and albatross diving abilities. Sink rates of lines deployed into ... propeller turbulence, which tended to keep lines aloft, varied as a function of distance between line ... results of experiments are to be meaningful. This is particularly so in the case of experiments aimed at ... a line length on the seabed of about 13 km (depending on slack in the line). The line was set at ... at 5.5-6.5 knots and bait shooting rate, which varies as a function of setting speed and snood ... within 70 m of weights attached to the mother line at 1 600 m intervals. Branch lines were 18 m in ...
Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 133–150 : Auteur(s): Robertson, G.G
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Investigations of required sampling regimes for environmental parameters
Paper Title: Investigations of required sampling regimes for environmental parameters Abstract ... / Description: The sensitivity of different sampling regimes in identifying inter-annual changes in ... monthly mean temperature over two years with a significance α of 0.05 and a power P of 0.8. Sampling wind ... monthly mean log-transformed wind speed α of 0.05 and P of 0.9. File: 35-Agnew.pdf ... of the required sample size such that a certain level of change would be detectable at a ... significance level of a and at a power of P. The method of Sokal and Rohlf (1981) was used along the ... . The occurrence of cyclic phenomena at Davis Station, including the suspected occurrence of cycles in ... temperature change of ±2°C in December and January could be reliably detected at Davis Station, but that in ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 561–573 : Auteur(s): Agnew, D.J.
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Calibration of an acoustic echo-integration system in a deep tank, with system gain comparisons over standard sphere material, water temperature and time
Paper Title: Calibration of an acoustic echo-integration system in a deep tank, with system gain ... sphere. It presents the results of an extensive calibration of a Simrad EK500 scientific echosounder with ... gain, including the effects of temperature, standard sphere and time, is 2.9 dB. Gain values calibrated ... with the Cu sphere are, with the exception of the long pulse length, lower than those from the WC ... each pair of transducer leads. Transducer resistances should be measured at all accessible points ... . Although the impedence of transducers is usually tuned in the factory to be 60 n at the nominal operating ... with three nylon cords in the centre of the tank at a depth of 0.5 m. It was connected to the EK500 ... ° alongship and athwartship angles, and at 0.5° C (Figure 2). By maintaining near zero offset (±1°) in one of ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 127–144 : Auteur(s): Demer, D.A. and R.P. Hewitt
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Protecting young fish and spawning aggregations of Champsocephalus gunnari in Subarea 48.3 (South Georgia): a review
Paper Title: Protecting young fish and spawning aggregations of Champsocephalus gunnari in ... measures put in place by CCAMLR to date. These measures are re-examined in the light of new information ... , and a strategy for the future protection of young fish and spawning aggregations of C. gunnari in ... Subarea 48.3 is considered. This comprises a combination of existing measures, including minimum mesh size ... of C. gunnari from 2-3 years old to 3-4 years old, particularly at high fishing mortalities ... (greater than 0.6). Relative benefits at low fishing mortalities (in the region of 0.2) were much less ... and Minimum Size Limits One of the most commonly used approaches to increasing the age at first ... setting of closed seasons if they are more vulnerable to capture at certain times of the year. In ...
Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 75–86 : Auteur(s): Parkes, G.B
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Research currently being undertaken by the Republic of South Africa on "dependent and related species" within the Antarctic marine ecosystem
Paper Title: Research currently being undertaken by the Republic of South Africa on " ... components of the biological sciences programme are described. The primary objective of the studies being ... undertaken is to improve our understanding of the ecology of important predators (especially seals and ... nearllal 93 Per (;ent of the world '5tock of this spec [es, hat; be~Jn est imwted at 200 000 and is ... increasing at a r;3t,(,! of about 16 Per cent Per i:iear. Distribution of these seals ar-mmd the shore of ... durins 1!J73 and indicate a decrease of 5 to 11 Per cent Per !:lear in the flOPulations at Mari on (4 ... acti1,1ities of elephant .an,j fur -.;eats i.,hen ashore at Mar-ion Island to breed or moult ha1,1e an imPor ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/2 (Selected Scientific Papers, SC-CAMLR-SSP/2) : 59-77 : Auteur(s): South Africa
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The CCAMLR-2000 Krill Synoptic Survey: a description of the rationale and design
Paper Title: The CCAMLR-2000 Krill Synoptic Survey: a description of the rationale and design ... Abstract / Description: The design of the CCAMLR-2000 Krill Synoptic Survey (CCAMLR-2000 Survey) is ... described. The primary objective of the survey was to improve estimates of the pre-exploitation biomass of ... the north of the Antarctic Peninsula (CCAMLR Statistical Subareas 48.1,48.2,48.3 and 48.4). Within ... . The grid shift was chosen by picking one of these potential grid positions at random. Tl-te same ... time at each station and make any necessary adjustments in the following order of priority ... the for the given dates for set positions on each expected time at the approxilllate mid-point of ... current transect and recommence surveying at the start of the next; else, To facilitate cruise planning ...
Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 1–23 : Auteur(s): Trathan, P.N., J.L. Watkins, A.W.A. Murray, A.S. Brierley, I. Everson, C. Goss, J. Priddle, K. Reid, P. Ward, R. Hewitt, D. Demer, M. Naganobu, S. Kawaguchi, V. Sushin, S.M. Kasatkina, S. Hedley, S. Kim and T. Pauly
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Management and uncertainty: the example of South Georgia
Paper Title: Management and uncertainty: the example of South Georgia Abstract / Description ... : Decisions on fishery management are often made with some degree of uncertainty in scientific advice. Such ... to consider ways in which CCAMLR can improve its ability to take decisions in the face of uncertainty ... . From an examination of Articles IX 2(f) and XV 2(e, d) of the CCAMLR Convention it follows that a ... the stock of Notothenia rossii is at an extremely low level. Proposals have been made in both the ... level at which they could provide sustained yields of y thousand tons per year, and that any other ... Figure 2 of the working party report it appears that mortality has increased from 0.11 to 0.76, i.e. at ... view would be to challenge the general interpretation, and look at some of the inconsistencies of ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 341-353 : Auteur(s): Gulland, J.A.
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On reproduction of Electrona carlsbergi (Tåning)
Paper Title: On reproduction of Electrona carlsbergi (Tåning) Abstract / Description: This paper ... presents results from histological examinations of gonads of Electrona carlsbergi from the Atlantic sector ... of the Southern Ocean. From materials available it has been ascertained that E. carlsbergi spawns in ... the notal waters. Maturation of females begins when body length reaches 76 to 78 mm. Vitellogenesis is ... cytoplasm develops in oocytes. Later, the growth of oocytes occurs at the expense of an increase in the ... monolayer follicle. At the beginning of slow growth oocytes are usually of regular shape and have a ... intensity of colour in its different parts varies. At the end of the protoplasmatic growth period, the ... , the amount of trophic substance increases at the expense of accumulation of yolk granules of ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 397–409 : Auteur(s): Mazhirina, G.P.
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Distribution of krill (Euphausia superba Dana) catches in the South Shetlands and South Orkneys
Paper Title: Distribution of krill (Euphausia superba Dana) catches in the South Shetlands and ... South Orkneys Abstract / Description: A set of concentric zones of 20 km width was defined around ... selected colonies of penguins distributed around the coasts of the South Shetland and South Orkney Islands ... distribution in Subarea 48.2, probably as a result of more variable hydrographic conditions. About 50% of the ... -exploitation brought at least some stocks to the verge of extinction. A further concern was that harvesting ... species is estimated as within a 10 to 90 km radius of breeding sites at these times of year: Ad6lie ... occurs at levels of fishing mortality that are lower than natural mortality. The assumption here is that ... predator populations are utilising the food resource (krill) at levels of natural mortality that allow the ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 287–303 : Auteur(s): Agnew, D.J.
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Low genetic diversity and temporal stability in the Antarctic toothfish (Dissostichus mawsoni) from near-continental seas of Antarctica
(Dissostichus mawsoni) from near-continental seas of Antarctica Abstract / Description: This study presents ... data on the DNA analysis of recent (2011–2013) samplings of Antarctic toothfish (Dissostichus mawsoni ... analysis of the most informative subset of nuclear genetic markers of SNP variation presented in Kuhn and ... Gaffney (2008), do not support genetic differentiation of samples from the Ross Sea. Discrepancies in the ... late 1990s and the fleet use mainly bottom-set longlines at depths of 1 200–1 800 m. Defining the ... -water) stage occurs when fish reach 100 cm in length and migrate to deep waters and stay at a depth of ... cycle protocol: a pre- liminary denaturation of DNA at 94°C for 1 min was followed by syntheses of DNA ... products: melt- ing at 92°C for 20 sec, annealing of primers at 55°C for 40 sec, DNA syntheses at 72°C for ...
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