Sökning: "hydroacoustic"

Hittade 2 avhandlingar innehållade ordet hydroacoustic.

1. 1. Pelagic Fish Distribution and Dynamics in Coastal Areas in the Baltic Sea Proper

   Författare :Thomas Axenrot; Sture Hansson; Stein Kaartvedt; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; herring; Baltic; hydroacoustic; distribution; behaviour; Biology; Biologi;

   Sammanfattning : Pelagic fish distribution and diel behaviour patterns were studied in coastal areas in the north-western Baltic Sea Proper to understand more about how fish distribution and behaviour might affect planning and analyses of results of hydroacoustic surveys (Papers I and II). The vertical distribution of fish at night from spring to autumn showed seasonal and annual trends that could be explained by predictable and consistent seasonal changes, e. LÄS MER

3. 2. Distribution and activity of pelagic fish - acoustic studies in the Baltic Sea

   Författare :Tomas Didrikas; Sture Hansson; Thomas Mehner; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pelagic; fish; hydroacoustic; distribution; activity; Baltic; Biology; Biologi;

   Sammanfattning : Fisheries agencies around the Baltic Sea use hydroacoustics to assess stock sizes of herring and sprat. These assessments rely on the assumption that the acoustic properties of Baltic clupeids are the same as North Sea herring. LÄS MER