Результаты поиска

1. Australian research on Antarctic bird and seal diets

   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 ... Cephalopods 6 100 18 241 E. superba were 100% of contents in all but one stomach, and the mean ... initially in response to the need identified by the BIOMASS Programme for data on the diets of vertebrate ... Davis Station (68°30'S:77°50'E), in the south-eastern corner of the Prydz Bay Priority Area of CEMP ... Euphausia superba Cephalopods Others 13.8 8S.S O.S 0.2 P. antarcticum comprised SO% of the diet in ...

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

2. Modelling krill recruitment

   observed values of the mean proportion of recruits and its variance to model recruitment in a krill ... population in terms of numbers of recruits. The method includes the calculation of natural mortality and ... for generating families of recruitment functions which are consistent with the statistical uncertainty ... in the observed recruitment parameters.  File:  04delamare-mod-rec.pdf ... recruitment, in terms of a mean and variance. The aim of this paper is to present a me thod of us ing ... mean and variance in the proportion of recruits, into random numbers of recruits, which in ... simulations will reproduce the observed mean and variance in the proportion of recruits. The proportion of ... and its variance to model recruitment in a krill population in terms of numbers of recruits. The ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 49–54 : Автор(ы): W.K. de la Mare

3. Estimating krill recruitment and its variability

   surveys in the South Atlantic and the Indian Ocean sectors of the Southern Ocean give a mean recruitment ... likelihood method is developed for the decomposition of krill density-at-length data into the proportion of ... recruits in a population sampled by a net haul survey. Preliminary results from a series of five net haul ... rate for 1+ krill (the ratio of the number of krill aged one year to the number of krill aged one year ... sampling distribution. The likelihood for the sampling distribution of the mean cannot be expressed in ... in boldface are used in calculating the mean and variance of R(f). The estimates of the inverse ... variance weighted mean and variance of the R(1) estimates, taking the group with mean length in the range ... ), taking the second group with mean length in the range 30 to 38 mm as age class 2, are: Number of ...

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

4. Choosing distance between acoustic survey tacks

   on the basis of typical size of the surveyed region, allowable relative error in the biomass estimate ... , and the variation coefficient of the density values of the krill concentrations. It is recommended ... that the suggested criterion be applied in real hydroacoustic surveys. File:  08-Kalikhman-et-al.pdf ... mathematical model was used to show that the distance between acoustic survey tacks can reasonably be selected ... on the basis of typical size of the surveyed region, allowable relative error in the biomass ... as to provide the desired accuracy of the biomass assessment in the area, in the least time and ... with the lowest expenditure. Since the error in biomass assessment depends on the variability of ... - the coefficient of variation of density values in the given area*. Developing criteria for ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 153-164 : Автор(ы): Kalikhman, I.L., Z.I. Kizner, B.R. Zaripov and W.D. Tesler

5. International CCAMLR applied research and monitoring program, Prydz Bay priority area

   Australia towards the first five years of an International CCAMLR Applied Research and Monitoring Program in ... the Prydz Bay area. Emphasis is placed on the krill based part of the marine community in the Prydz ... Bay area. Some attention is also given to the fish and squid based part of the marine community on the ... area Abstract / Description:  An outline is given of a proposed scientific research contribution by ... the krill based part of the marine community in the Prydz Bay area. Some attention is also given to ... confirmed by other member countries at the Fourth Meeting of the Scientific Committee of CCAMLR in ... contribution places emphasis upon the krill (and other invertebrate) based part of the community in the Prydz ... year to year fluctuation in the abundance and distribution of the selected consumers and their key ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 283-295 : Автор(ы): Australia

6. Toothfish, Dissostichus eleginoides, at South Georgia

   longliner in January 1990 indicates that the fish are sexually mature and, at the time of sampling, are ... , paragraph 106). Histological examination of the gonads of a small sample of fish taken from a commercial ... Paper Title:  Toothfish, Dissostichus eleginoides, at South Georgia Abstract / Description:  The ... Dissostichus eleginoides fishery at South Georgia has expanded greatly in recent years. It has been claimed ... examination of the gonads of a small sample of fish taken from a commerciallongliner in January 1990 ... longline fishery was justified (CCAMLR-VIII, paragraph 106). We know of no fishery anywhere in the World ... in the vicinity of Shag Rocks. The fish were measured, weighed and sex and maturity stage determined ... of gonads, samples were frozen for histological examination in the UK. Otoliths and scale samples ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 255–261 : Автор(ы): Everson, I. and S. Campbell

7. Trawl selectivity for Champsocephalus gunnari

   selectivity for mackerel icefish (Champsocephalus gunnari L.), were collected in 1981 in the South Georgia ... area. The trawl bags tested were made of net webbing with 3.1 mm twine and 88.2 mm mesh size. Trawling ... speed was 3.5 knots. Icefish comprised 90 to 100% of catches. The logistic selectivity curves were ... calculated using the collected data. It was found that the selectivity factor for 88.2 mm mesh size was 2.81 ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/6 (Selected Scientific Papers, SC-CAMLR-SSP/6) : 69–75 : Автор(ы): Efanov, S.F., G.E. Bidenko and V.A. Boronin

8. Estimating confidence intervals for fish stock abundance estimates from trawl surveys

   the nominal coverage probability. Performance deteriorates in cases where few of the hauls contain ... estimates of abundance obtained from trawl surveys conducted by means of the swept area method, using ... likelihood ratios from Aitchison's delta distribution. Simulation tests of the method show that unbiased ... estimates of density and biomass can be obtained and that the estimated confidence intervals have close to ... is the mean density in stratum j, and A, is its area. The variance of B is given by: ~ ~ Y ( X ... deteriorates in cases where few of the hauls contain fish and the coefficient of variation (CV) is high. The ... attention, as a matter of priority, to the difficulties which had been experienced in the application of ... statisticians. This paper addresses some of the statistical issues which are of concern in the analysis of ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 203–207 : Автор(ы): de la Mare, W.K

9. Integrating Count Effort by Seasonally Correcting Animal Population Estimates (ICESCAPE): a method for estimating abundance and its uncertainty from count data using Adélie penguins as a case study

   reported measures of uncertainty associated with originally published counts are propagated through to the ... , the method is applied to several examples of published studies of Adélie penguin abundance at breeding ... sites in Antarctica. These examples focus on adjusting counts of adults to an effective number of ... breeding pairs, although the software has been developed to accommodate adjustment and aggregation of other ... some larger area of interest so that, in order to obtain estimates of total population size for the ... estimating the abundance of colonial land-breeding vertebrate species in Antarctica and on sub-Antarctic ... demonstrate application of the technique. For penguins in general, and Adélie penguins in particular, most ... the breeding population as the number of breeding pairs or nests present one week after the peak in ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 213–227 : Автор(ы): McKinlay, J., C. Southwell and R. Trebilco

10. Note on estimating krill abundance from acoustic data on individual aggregations

    Abstract / Description:  The fundamental equations and assumptions underlying estimation of krill abundance ... differences of the two approaches are highlighted. It is concluded that the echo-integration approach is ... superior for the estimation of regional krill abundance and its variance since it is easier to apply ... using echo-integration information and aggregation parameters are briefly described. The chief ... (WG-Krill) emphasised the importance of acoustic techniques in the determination of krill abundance ... over large geographical areas. The approach differs from echo-integration in that use is made of ... to ESDU length) average of the P j values. Variance can be estimated formally from the variation in ... estimated from Equation 1 as before. If the aggregation data is available in terms of density rather than ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 219–223 : Автор(ы): Hampton, I. and D.G.M. Miller

Страницы