Search results
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Estimation of natural mortality using catch-at-age and aged mark-recapture data: a multi-cohort simulation study comparing estimation for a model based on the Baranov equations versus a new mortality equation.
the mean (i.e. the expected value across years) recruitment of age-1 fish, defining the parameter K0 ... AS S , where there are A age-classes considered for the population (i.e. so that Sa has a mean of 1), rather ... of mean age-1 recruitment, K0, is available, com- bined with an estimate of the series of YCS, Γ pfy ... parameters that is close to 1, given by ( ){ }2ˆ10000 1Γ -mean was added to the above –2 log-likelihood ... functional form of selectivity was correctly specified in the BODE model, both models gave close to unbiased ... selectivity function, the bias and imprecision in estimates of M increased by no more than 2% for the CCODE ... number of recaptures-at-age and model the population numbersat- age by annual difference equations ... of 500 000. Simulations which passed catch-at-age numbers to the estimation algorithm after ...
Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 1–27 : Author(s): Candy, S.G.
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On the intensity of sampling krill trawl catches
statistically meaningful differences between samples; and • the problem of how frequently commercial krill ... is necessary to obtain statistically meaningful differences between samples; and • the problem of how ... detected differences in mean length should be in order to provide meaningful insights into the underlying ... size of at least 100 animalsltrawl is necessary to obtain statistically meaningful differences ... and to investigate differences in mean length between stations and between areas. Additional statistical procedures ... described in Zar (1984) were used to estimate projected sample sizes, based on variances in mean length ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 29–48 : Author(s): Miller, D.G.M.
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On the instantaneous natural mortality rate of Champsocephalus gunnari, South Georgia (Subarea 48.3)
) The Beverton-Holt Method (1956): -where t t' = mean age in the catch; M=_I_ t - t l = ftrst age group ... and for the period as a whole is shown in Table 3. Mean length by age group for each season was calculated ... as the mean weighted value of length for each age group (Table 4). The data presented served as a starting ... point for determination of parameters of Bertalanffy's growth curve (Table 5). Values for mean length ... composition of catches from 1964/65 to 1968/69 and the age/length key for the first half of 1972 were used in ... Paper Title: On the instantaneous natural mortality rate of Champsocephalus gunnari, South ... Georgia (Subarea 48.3) Abstract / Description: The instantaneous rate of natural mortality (M) of ... Champsocephalus gunnari in the South Georgia area was assessed using six different methods. Data on size ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 313–326 : Author(s): Frolkina, G.A. and R.S. Dorovskikh
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Chilean krill fishery: analysis of the 1991 season
, by definition, is the conservation of the Antarctic marine living resources. KriU is by far the most abundant ... :::> 0.. () E ::J E .~ ~ Figure 5: Mean CPUE for the Chilean krill fishery from 1987 to 1991. Data is presented by split-years ... data and its use in studying small-scale spatial distribution of catches. The results show that krill ... Paper Title: Chilean krill fishery: analysis of the 1991 season Abstract / Description: This ... paper summarises Chilean catch data for 1991. Special emphasis is given to the analysis of haul-by-haul ... fishing in Subarea 48.1 is particularly intense near CEMP sites. Other ways of using of haul-by-haul data ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 273–287 : Author(s): Marín, V.H., A. Mujica and P. Eberhard
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The effects of monitoring procedures on Adélie penguins
lavage and ins t rument at tachment (SC-CAMLR, 1991). Disturbance to individuals and colonies ... individually identified by means of either an electronic t r ansponde r tag (TIRISTM, Texas Instruments ... the second summer in an attempt to improve the streamlining of the package. Ins t ruments were ... a t tached to both male and female pengu ins d u r i n g their long incubation-period foraging trips ... Paper Title: The effects of monitoring procedures on Adélie penguins Abstract / Description: The ... effects of flipper bands, implanted tags, gastric lavage and external instrument attachment on the ... , Antarctica. The return rates of birds carrying bands and/or implanted electronic transponders were compared ... to investigate the contribution of bands to bird mortality and to determine rates of band and tag ...
Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 155–164 : Author(s): Clarke, J. and K. Kerry
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Preliminary appraisal of Antarctic fish selection by the 32/36 bottom trawl combined with various codends
BblCB060Al1TbCH 113 KYTKa. CeJIeKTI1BHble - 3 - cnoco6HOCTif 060HX neHTO'IHblX KYTKOB 6bInH ropa3Ao nY'IWe ... , with an ICES slide caliper (load of 4 daN) and calculated as a mean from 30 measurements. For investigations ... . Basic selectivity factors, i.e. mean fish length for three main selectivity levels : 25, 50 and 75 ... : selectivity interval consisting of the difference in cm between the mean length of fish for selectivity ... . It was found that the selectivity properties of twine codends are unsatisfactory in the case of ... Paper Title: Preliminary appraisal of Antarctic fish selection by the 32/36 bottom trawl combined ... , especially Scotia Sea icefish and South Georgia icefish the determination of a proper mesh size of trawls ... used in fishing for them requires further research. It should first of all cover twine codends with a ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 1-48 : Author(s): Zaucha, J.
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Quantification of Southern Ocean phytoplankton biomass and primary productivity via satellite observations and biogeochemical models (submitted to the 2008 Joint CCAMLR-IWC Workshop)
Resolution Imaging Spectroradiometer (MODIS) Aqua seasonal mean Fluorescence Line Height (FLH) for Austral ... ) and its products are readily available. Behrenfeld and Falkowski (1997b) used it to arrive at a mean ... have been applied to the Southern Ocean to derive (i) mean (per unit area) or total (spatially ... the per unit area productivity might be high in these regions, their small spatial extent means ... regard to their use in the Southern Ocean. A brief history of algorithms linking ocean colour to primary ... / Description: This paper reviews Southern Ocean primary productivity within the framework of satellite remote ... sensing and the development of food-web models. The satellite ocean colour (chlorophyll) data record is ... described, from the Coastal Zone Colour Scanner (CZCS) in the late 1970s through to the Ocean Colour and ...
Science Journal Paper : CCAMLR Science, Volume 19 (CCAMLR Science, Volume 19) : 247–265 : Author(s): P.G. Strutton, N.S. Lovenduski, M. Mongin and R. Matear
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An alternative method for estimating the level of illegal fishing using simulated scaling methods on detected effort
of this paper, particularly with regard to the behaviour of vessels when detected, mean that this method ... Table 2). This means that the results differ primarily by the multiplier that is used and so ... conservative) using the new method. One of the advantages of the new method is that it allows an estimation ... shing. This means that for a given number of illegal cruises there is a negative correlation between ... performs better in the case of zero detections and can potentially better handle the evasion of detection ... fishing (in the simulation datasets) for a given estimated level of fishing is very large. This range of ... Paper Title: An alternative method for estimating the level of illegal fishing using simulated ... effort is put forward. The results from this new method are similar to those of the Agnew and Kirkwood ...
Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 143–161 : Author(s): Ball, I
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Indices of prey availability near the Seal Island CEMP site: 1990 to 1996
C O r I I a C y W T C I I C . Q ~ M O T ~ ~ @ M Y ~ C K A M L ? A H A e K C a M B YI.ICIIeHH0CTI.I KpI.In5I, I I 0 n y Y e H H b I M I . I C n O M O U b W C e T e B b I X npo6 ... and averaged over each 100 m of distance along the trackline. For the purposes of this paper, mean volume ... - 31 Jan 17-28 Jan 16 - 29 Jar1 23 Jan - 4 Feb (ii) Mean distance of prey from Seal Island ... . (iii) Mean depth of prey, where D,,,,A is the mid-depth of the ith depth bin. (iv) Persistence ... / Description: Four indices of prey availability are calculated from surveys conducted in the vicinity of the ... Paper Title: Indices of prey availability near the Seal Island CEMP site: 1990 to 1996 Abstract ... Seal Island CEMP site during the austral summers of 1990 to 1996. The indices are measures of average ... surveys each year were subsampled to include the foraging range of predators breeding at Seal Island ...
Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 37–45 : Author(s): Hewitt, R.P., G. Watters and D.A. Demer
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Vertical migrations of mackerel icefish (Champsocephalus gunnari) on the South Georgia shelf
prospecciones de arrastre de C. gunnari durante el dfa solamente. 1. IN1RODUCTION Scientists of several ... in shelf waters of the South Georgia by means of trawl surveys. The assessment methodology suggested ... -21:00 Mean catch 2122 2054 '-------_1686 2997 L__ ·- 200_ ·- 300 ... commercial concentrations of C. gunnari in years of high abundance of the species (1982/83, 1983/84 and 1986 ... considered in the paper. A distinct pattern of daily vertical migrations of C. gunnari was observed on the ... Paper Title: Vertical migrations of mackerel icefish (Champsocephalus gunnari) on the South ... Georgia shelf Abstract / Description: High values of coefficient of variation resulting from the ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 3–14 : Author(s): Frolkina, J.A. and V.I. Shlibanov