Now showing items 315-334 of 3135

    • Data on the 1983 year class of Norwegian spring spawning herring from the period June 1985 -August 1986 

      Røttingen, Ingolf (ICES CM Documents;1986/H:19, Working paper, 1986)
      This paper considers the distribution, growth and migration of the 1983 year class of Norwegian spring spawning herring. There are, at present, two geographical components of this year class, one component with a nursery ...
    • Day / night variation in fish directivity in the trawl opening 

      Huse, Ingvar; Aglen, Asgeir; Engås, Arill; Godø, Olav Rune; West, Charles W. (ICES CM Documents;1994/B:18, Working paper, 1994)
      Still photographs of fish in the mouth area of a bottom trawl were taken by a downwards-oriented automated strobe camera mounted near the headrope. Fish angles relative to the towing direction were measured. Fish were ...
    • Deep towed vehicle for fish abundance estimation concept and testing 

      Dalen, John; Bodholt, Helge (ICES CM Documents;1991/B:53, Working paper, 1991)
      A research program was initiated in Norway in 1988 for measuring the abundance of fish resources at depth from 500 to 1000 metres. It was decided to develope a deep towed vehicle, to bring acoustic transducers down to ...
    • DEEPFISHMAN: Management And Monitoring Of Deep-sea Fisheries And Stocks 

      Lorance, Pascal; Arnason, Ragnar; Cloete, Rudi; Diez, Guzman; Dransfeld, Leonie; Failler, Pierre; Figueiredo, Ivone; Gil, Juan; González-Costas, Fernando; Hillary, Richard; Jacobdóttir, Klara; Large, Phil A.; Planque, Benjamin; Politou, Chrissi-Yianna (ICES CM documents;2009/N:22, Working paper, 2009)
      Deepwater fisheries pose particular difficulties for management. Target species are difficult to assess with adequate levels of certainty, they are slow growing and generally vulnerable to overfishing and many of these ...
    • Deepwater flowthrough as a temperature stabilizer in rearing of halibut (Hippoglossus hippoglossus) fry 

      Berg, Leif; Naas, Kjell Emil; Pittman, Karin (ICES CM Documents;1987/F:16, Working paper, 1987)
      Through the period of yolk sac absorption, halibut larvae were kept in plastic bags in plastic basins with flowthrough of deepwater. When maintaining sufficient flowthrough, in this period the temperature in the bags ...
    • Definition of the problem of estimating fish abundance over an area from acoustic line-transect measurements of density 

      Foote, Kenneth G.; Stefánsson, Gunnar (ICES CM Documents;1990/D:25, Working paper, 1990)
      The problem of acoustic abundance estimation is briefly reviewed. Under proper conditions, fish density can be measured with high accuracy along line transects. Observed variations in fish density consequently reflect ...
    • Demersal fish on the continental slope off Norway 

      Gjøsæter, Jakob (ICES CM documents;1975/F:29, Working paper, 1975)
      Investigations on distribution and abundance of demersal fish in 400-1000 m depth were carried out in three selected areas off Norway in July-August 1974. Based on catches in 48 hauls by bottom trawl and 3 long-line settings ...
    • Demersal pair trawling and its operational parameters. 

      Dickson, W.; Valdemarsen, John Willy (ICES CM Documents;1982/B:36, Working paper, 1982)
    • Demonstration of maternal effects of Atlantic cod: Combining the use of unique mesocosm and novel molecular techniques – A new EU-project 

      Svåsand, Terje; Ajiad, Adnan Mosa; Dahle, Geir; Jakobsen, Tore; Kjesbu, Olav Sigurd; Moksness, Erlend; Otterå, Håkon; Solemdal, Per; Thorsen, Anders (ICES CM documents, Working paper, 2000)
      One of the effects of fishing is a reduction in average age and size in exploited fish stocks, leading to an increasing proportion of recruit spawners in the stock. Current management practice assumes equal viability of ...
    • Density dependent catchability in bottom trawl surveys 

      Aglen, Asgeir; Engås, Arill; Godø, Olav Rune; McCallum, Barry R.; Stansbury, Don; Walsh, Stephen J. (ICES CM Documents;1997/W:16, Working paper, 1997)
      Fish form schools, layer or patches in which the individual fish's behaviour is not independent of its neighbours movements. On the other hand, at low densities fish may have the freedom to act as single individuals ...
    • Density driven currents in the Barents Sea calculated by a numerical model 

      Slagstad, Dag; Støle-Hansen, Kjell; Loeng, Harald (ICES CM Documents;1989/C:20, Working paper, 1989)
      A baroclinic, 3-D model is described. It is adapted to a Barents Sea situation in order to simulate the currents in this area. The model is of a so-called level type which contains fixed, but permeable levels. It also ...
    • Density in sub-arctic zooplankton 

      Falk-Petersen, Stig; Køgeler, J. W.; Kristensen, Åge; Pettersen, Fritz; Dalen, John (ICES CM documents, Working paper, 1985)
      Seasonal variations in specific density were measured for Thysanoessa inermis, Thysanoessa raschii, Meganyctiphanes norvegica, Calanus finmarchicus and Calanus hyperboreus. The density of a 20 mm T. inermis was lowest in ...
    • Density-Dependent Growth in Saithe 

      Olsen, Steinar (ICES CM Documents;1966/G:2, Working paper, 1966)
    • Dependence of equivalent beam angle on sound speed 

      Foote, Kenneth G. (ICES CM documents, Working paper, 1987)
      The equivalent beam angle is computed numericaily, according to its rigorous definition, for each of two transducers. These are those used with the SIMRAD split-beam echo sounders at 38 and 70 kHz. The results are expressed ...
    • Description of the Norwegian/Russian stomach data set 

      Bogstad, Bjarte; Mehl, Sigbjørn (Working paper, 1992)
    • The design and use of a profiling instrument for measuring and recording physical variables in the sea 

      Gytre, Trygve (ICES CM Documents;1977/C:22, Working paper, 1977)
      The paper describes a measuring system for profiling of the upper few hundred meters of the sea. The system consists of a recording instrument and a readout unit. The recording instrument has sensors for current, direction, ...
    • Designing an improved transducer array geometry 

      Foote, Kenneth G. (ICES CM Documents;1988/B:2, Working paper, 1988)
      Improvements in a split-beam transducer that is also used for surveying are sought through changes in array geometry. These are assessed through relative changes in the sum of source level and voltage response and the ...
    • Designing an Ocean Mid-trophic Automatic Acoustic Sampler (MAAS) - thoughts on how to include echo sounder observatories in ecosystem models 

      Handegard, Nils Olav; Domokos, Réka; Godø, Olav Rune; Jouanno, Julien; Kloser, Rudy; Lehodey, Patrick; Maury, Olivier; Senina, Inna (ICES CM documents;2009/I:21, Working paper, 2009)
      Echo sounders are a widely used tool for observing marine ecosystems. Traditionally, carefully designed surveys are used to integrate biomass to a global estimate, which is coupled to traditional stock assessment models. ...
    • Detailed in situ target strength measurements of 0-group cod 

      Ona, Egil (ICES CM Documents;1994/B:30, Working paper, 1994)
      Target strength measurements in situ of cod fry have been made using 38 and 120 kHz split beam echo sounders. Two data sets are sampled in essentially pure, evenly sized, cod concentrations, one in a Ullsfjord, Northern ...
    • Detection and counting of individual free-swimming krill using a 2MHz scanning sonar 

      Ona, Egil; Knutsen, Tor (ICES CM Documents;1992/L:18, Working paper, 1992)
      The euphausiid crustacean Meganyctiphanes norvegica (M. Sars) have been detected and counted in the scanning section of a 2 MHz scanning sonar beam up to 3 meters from the sonar head. The tests completes a pilot investigation ...