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Performance and geometry of the FP-120 trawl used during UK fish stock assessment surveys around South Georgia, Subarea 48.3
Paper Title: Performance and geometry of the FP-120 trawl used during UK fish stock assessment ... opening (and, thus, swept area) of a bottom trawl are discussed. In situ measurements of the FP-120 trawl ... presented. Regression equations for the estimation of horizontal opening from other, more easily measured ... around South Georgia are estimated using a new regression equation. The results of this calculation are ... , swept area S can be estimated at the ith location by: start and end of each tow using a Furuno GPS ... mounted at the midpoint of the headline. Additional floats were attached to counteract the negative ... fixing of the Scanmar sensors on the FP-120. Pilling and Parkes The sensors were deployed at 29 of ... measurements of the horizontal opening resulted. The mountings of the sensors were checked at the end of each ...
Science Journal Paper : CCAMLR Science, Volume 2 (CCAMLR Science, Volume 2) : 51–69 : Autor(es): Pilling, G. and G. Parkes
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The choice of procedure for deciding when to close fisheries regulated by CCAMLR: a simulation model
Paper Title: The choice of procedure for deciding when to close fisheries regulated by CCAMLR: a ... deciding the closure date for fisheries monitored by the Secretariat of CCAMLR, have been difficult to ... implement because of the variation in catch rates shown by the fisheries. Non-fluctuating random and ... fluctuating random catch histories are simulated and the performance of four models for making closure ... falling due at the end of the period following that in which catches are taken; • the Secretariat should ... further the performance of various methods of arriving at a closure decision and to develop methods with ... amplitude of the sin wave, 9 is the position of the sinusoidal cycle at time t computed from the equation 9 ... the report at the Secretariat in days, P = length of the reporting period in days, a = mean delay, s ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 81–97 : Autor(es): Agnew, D.J.
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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 : Autor(es): 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 : Autor(es): 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 : Autor(es): 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 : Autor(es): 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 : Autor(es): 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 : Autor(es): 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 : Autor(es): 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 : Autor(es): Mazhirina, G.P.