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1. Fish stock assessment survey in Subarea 48.3

   . The locations of the sites actually sampled are shown in Figure 1 and the positions given in Table 1. The mean ... . The data from the age and length distributions have been combined to provide mean length and mean weight ... 128 130 94 93 54 54 158 144 126 125 96 94 55 54 148 147 128 129 94 94 53 53 Mean: 149.8 127.3 93.8 ... I '-- -- --'- -'- """ o Table 12: Mean length (cm) at age for length and age samples taken during the survey. All values ... fish survey in the vicinity of South Georgia, CCAMLR Subarea 48.3, is described. Details are given of ... positions of hauls, catch rates and size composition of catches. The standing stock of one of the most ... important commercial species in the area, Champsocephalus gunnari, is shown to have undergone a major ... Paper Title:  Fish stock assessment survey in Subarea 48.3 Abstract / Description:  A demersal ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 25–67 : Author(s): Everson, I., G. Parkes, K.-H. Kock, S. Campbell, Z. Cielniaszek and J. Szlakowski

2. Revised age and growth estimates for Antarctic starry skate (Amblyraja georgiana) from the Ross Sea

   ) and mean coefficient of variation (CV) for each skate were calculated to assess ageing precision (Campana ... and error bars indicate the mean and two standard errors for read- ings on the y-axis relative ... . By counting fine growth bands in the caudal thorns instead of broad diffuse bands, growth curves have ... ) from the Ross Sea Abstract / Description:  A previous study on the age and growth of Amblyraja ... georgiana in the Ross Sea suggested that these skates initially grow very rapidly for about five years ... and growth in A. georgiana that is radically different from the published interpretation is presented ...

   Science Journal Paper : CCAMLR Science, Volume 16 (CCAMLR Science, Volume 16) : 211–220 : Author(s): Francis, M.P. and M.J. Gallagher

3. Modelling variability and estimating power to detect change in Adélie penguin fledgling weights

   is a random adjustment to mean weight for year i, B is the slope (average rate of change in weight per five ... and eij terms are independent and are normally distributed with mean 0 and vari- ance 2Sσ , 2 stσ ... of data over eight years for five-day periods 2–5 indi- cated a significant relation between mean ... (2) were employed in equation (3) to estimate mean weight as a function of five-day period x: ˆ xM ... the number of birds weighed in each five-day period from 50 to 30 without substantial loss of power ... fledgling weights Abstract / Description:  Statistical models of variation in Adélie penguin fledgling ... weight data were used to examine the power to detect a change in fledgling weights after an impact. The ... year, but there was no evidence that the rate of decline differed between years. A consequence of this ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 191–200 : Author(s): Emmerson, L.M., C. Southwell and J. Clarke

4. Some thoughts on precautionary measures for the krill fishery

   A fundamental aim of establishing conservation measures for a harvested resource is to ensure that harvesting ... estimates can be made, leading to more precise conservation measures. Article I1 of the CCAMLR Convention ... and harvesting. The FIBEX survey took place in the 1980/81 season, over a decade ago, which means ... been determined by direct field observations and by means of micro-encapsulated instrument packages ... :  The concept of precautionary measures for krill is discussed. A precautionary catch limit, based on ... precautionary catch limit in large areas, such as Statistical Area 48, but the approach requires considerable ... takes account of the requirements of land-based predators. Implementation of the approach is discussed ... and the question of how the method relates to the current CCAMLR Ecosystem Monitoring Program (CEMP ...

   Science Journal Paper : CCAMLR Science, Volume 3 (CCAMLR Science, Volume 3) : 1–11 : Author(s): Everson, I. and W.K. de la Mare

5. Australian research on Antarctic bird and seal diets

   using Ipecac (emetic) Reference: Whitehead, Johnstone and Burton (in preparation) Mean weight of all ... by single water offloading Reference: Puddicombe and Johnstone (1988) Mean weight of all food: Pre ... Lysianassidae and Eusiridae. Prey size (length range, mean ±SD millimetres): E. superba E. crystallorophias ... obtained by single water offloading Reference: Green and Johnstone (1988) Mean weight of all food ... data on the diets of important vertebrate predator species in Prydz Bay and around the sub-Antarctic ... rather low proportion of the diet of most vertebrate predators. Euphausia crystallorophias and the fish ... Pleuragramma antarcticum are important in most diets, and many predators can switch between prey species. The ... use of these predators to monitor the state of prey populations is thus very limited, although ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II) : 231-249 : Author(s): Williams, R.

6. Estimating krill recruitment and its variability

   surveys in the South Atlantic and the Indian Ocean sectors of the Southern Ocean give a mean recruitment ... a mean recruitment rate for 1+ krill (the ratio of the number of krill aged one year to the number ... Ocean sectors of the Southern Ocean give a mean recruitment rate for l+ krill (the ratio of the number ... standard normal function, p, is the mean of the length distribution for animals of age i. The values ... observations. Simulation studies show that the sampling distribution of the mean for delta distributions ... of the data or their mean do not lead to summary statistics which capture all the features of the sampling ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 55–69 : Author(s): de la Mare, W.K

7. Using ecosystem monitoring data to detect impacts

   or explicit focus of conservation objectives for animal populations. Furthermore, the state of indicator ... strategies that use uncontrolled perform- ance data to meet conservation objectives remains a significant ... of the harvested species. There is, therefore, a need to define operational conservation objectives ... information about the state of the monitored populations and, therefore, whether conservation objectives ... an observed value in an unimpacted system, or (ii) the frequency of values below a fixed reference ... purpose of ecosystem monitoring programs is to indicate the state of ecosystems and whether they have been ... using monitoring data with no control sites. These methods assess either (i) the expected probability of ... point. The second approach allows inference criteria based on changes in this frequency rather than by ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 197–212 : Author(s): Hill, S.L., J. Forcada, P.N. Trathan and C.M. Waluda

8. Fishing for toothfish using pots: results of trials undertaken around South Georgia, March–May 2000

   Conservation Measure 64/XII. According to this protocol, fishing was to be conducted over as wide an area ... line 128 1.28 kg/ ot, 128 k per 5 km line 2 788 0.35 kg/Eook, 830&g per 5 km line Table 4: Mean ... by decRliing abundance on setting. Species Mean Number Observed Setting Hauling White-chinned petrel ... generally large (mean size of 94 cm, 64% 90 cm or above). Most fish discarded for this reason were dead ... commercial viability of this fishing method for toothfish fisheries in the CCAMLR Convention Area. While the ... toothfish was notably lower than that achieved in the longline fishery. Importantly, the use of pots ... , March–May 2000 Abstract / Description:  During the period March to May 2000, the UK undertook trials of ... method successfully caught D. eleginoides, there was a large by-catch of crab species. The catch rate of ...

   Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 93–105 : Author(s): Agnew, D.J., T.M. Daw, G.M. Pilling and M.G. Purves

9. 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

   in- vestigate the shape of the length-frequency compo- sition, e.g. through mean length or an upper length ... -class can result initially in decreasing mean length, and as the cohort grows, mean length steadily ... , if recruitment fails, e.g. because of low spawning biomass, mean length may increase since small fish no longer ... the reliable estimation of fishing or total mortality (see also simulations below). Mean length, maximum ... development. The failure of the tag-recapture program to provide robust assessments in many areas and doubts ... / Description:  In many of CCAMLR’s new and exploratory fisheries, stock assessment techniques are still in ... and fishing mortality from length-frequency data alone. In this paper, a number of length-based stock ... Paper Title:  Length-based assessments revisited – why stock status and fishing mortality of long ...

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

10. Brief comments on the simulation study made by Professor Butterworth on krill fishing by an individual Japanese trawler

    as meaningful as possible by using most of the information available at present. His model, however, presents ... questions are raised concerning the simulation study of the Japanese krill fishery carried out by ... during FIBEX surveys. Since very little searching time is spent on layers, the utility of searching time ... data appears doubtful. Secondly, the utility of indices based on the sum of primary and secondary ... searching times (PST+SST) is also doubtful because SSTs are markedly dependent upon the type of products ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/6 (Selected Scientific Papers, SC-CAMLR-SSP/6) : 347–350 : Author(s): Ichii, T. and Y. Endo

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