WG-KRILL-90

Differences in the target strength of adult Antarctic krill (Euphausia Superba) at 38 and 120 kHz have been inferred from differences in the mean back-scattering strength of swarms simultaneously insonified at these two frequencies in studies off the South Orkneys and Elephant Island in March 1990. Krill in these areas varied in total length between 36 and 60mm. Backscattering strengths at 120 Read More
Soumis par:
Admin Admin (Secrétariat de la CCAMLR)

Demander un document de réunion

This paper uses actual krill length frequency data in an attempt to address the problem of determining adequate sample size to obtain representative krill length frequency distributions from commercial catches. In addition, the possible effect of two other factors (within-trawl variability and sample decomposition) which may influence length frequency data quality are also considered. The Read More
Soumis par:
Admin Admin (Secrétariat de la CCAMLR)

Demander un document de réunion

We have no standard as to how many krill we should measure to obtain reliable estimates on its body length distribution. Krill samples collected from layers in the northern waters of Livingston Island were used in this study to get fundamental information on this problem. Based on the measurements of 2000 animals per sample, comparisons were made in mean body length and cumulative frequency Read More
Soumis par:
Admin Admin (Secrétariat de la CCAMLR)

Demander un document de réunion

Hydrological conditions, the distributiion pattern of krill and characteristics of the Soviet krill fishery off the Wilkes Land and Balleny Islands in 1988 and 1989 are described. The variability of some CPUE indeces (TC/TH/PPST; TC/TFISHT; TC/TFISHT/PPST) is analysed on the basis of data obtained aboard the Soviet trawler “Kapitan Oleinichuck".
The waters off the Terre d'Adelie (130° - Read More
Soumis par:
Admin Admin (Secrétariat de la CCAMLR)

Demander un document de réunion

A brief review of the objectives of the Convention for the Conservation of Antarctic Marine Living Resources is given along with an outline of for the evolution of management procedures for krill fisheries. Various possible elements of procedures such as reactive, predictive, and feedback management, modelling, indicator species, pulse fishing, and the use of open and closed areas and seasons Read More
Soumis par:
Admin Admin (Secrétariat de la CCAMLR)

Demander un document de réunion

Everson et. al. (1988), Foote et. al. (1990), and Everson et. al. (1990) are all based on the same experiment and report new calculations of the target strength of krill (Euphausia superba) that propose questioning previous measurements of krill target strength and estimates of abundance derived from them. Their results can be shown to have significant weaknesses in both data used and Read More
Soumis par:
Admin Admin (Secrétariat de la CCAMLR)

Demander un document de réunion

The homogeneity of krill length composition in commercial trawl catches (hauls) was investigated by comparing length compositions from different parts of the same haul. There was no significant difference (P>0.05) in 53 out of 60 hauls. Therefore it is concluded that sampling from one part of the haul provides a reasonable estimate of length composition in the entire haul as a whole. In Read More
Soumis par:
Admin Admin (Secrétariat de la CCAMLR)

Demander un document de réunion