Journal Article

Behaviour of mackerel schools during summer feeding migration in the Norwegian Sea, as observed from fishing vessel sonars

Olav Rune Godø, Vidar Hjellvik, Svein A. Iversen, Aril Slotte, Eirik Tenningen and Terje Torkelsen

in ICES Journal of Marine Science

Published on behalf of ICES/CIEM

Volume 61, issue 7, pages 1093-1099
Published in print January 2004 | ISSN: 1054-3139
Published online January 2004 | e-ISSN: 1095-9289 | DOI: http://dx.doi.org/10.1016/j.icesjms.2004.06.009
Behaviour of mackerel schools during summer feeding migration in the Norwegian Sea, as observed from fishing vessel sonars

More Like This

Show all results sharing these subjects:

  • Environmental Science
  • Marine and Estuarine Biology

GO

Show Summary Details

Preview

In July 2002, two commercial vessels were used to study the distribution of Northeast Atlantic mackerel (Scomber scombrus L.) during their feeding migration in the eastern part of the Norwegian Sea between 62°N and 70°N. Pelagic trawling and school tracking with SIMRAD 24–36 kHz sonar demonstrated that the stock was distributed throughout the study area. Information about time, geographic position, size, depth, speed, and direction was stored for each school during tracking. This study reports analyses of data from 63 schools that were tracked for 30 s or longer. All schools were recorded at depths of less than 100 m, and the majority (65%) were found between the surface and 40 m. The direction of migration (north 0° ± 22.5°, northeast 45° ± 22.5°, etc.) was non-random, with east and west as dominant swimming directions. School size and migration speed varied from 1 to 7000 tonnes and 0 to 6 m s−1, respectively. Methodological improvements are discussed.

Keywords: commercial vessels; distribution; mackerel; migration; school tracking; sonar

Journal Article.  3538 words.  Illustrated.

Subjects: Environmental Science ; Marine and Estuarine Biology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.