Blar i Brage IMR på emneord "schooling fish"
Viser treff 1-10 av 10
-
Computerbased detection of schools for counting, quantification of size and swimming behavior by the SIMRAD SA950 sonar
(ICES CM Documents;1993/B:17, Working paper, 1993)As a help in stock assessment of pelagic, schooling fish a software for detection of schools and quantification of their size and swimming behaviour by a high resolution sonar has been developed. The system reads the ... -
Dynamics of moving masses: Variability in packing density and shape among pelagic schools
(ICES CM Documents;1990/B:40, Working paper, 1990)The packing density and external shape of herring, saithe and sprat schools in the North Sea and along the Norwegian coast are measured acoustically. The packing density was inversely. related to the fish size, but species ... -
Hvorfor svømmer fisk i sirkel? Hvordan tas avgjørelser når en million fisk svømmer sammen og fungerer som en enhet? : Why do fish swim in circles?
(Havforskningsnytt, Working paper, 2007) -
Mapping the migration pattern of schooling fish by use of multi-beam sonar during conventional acoustic surveys
(ICES CM Documents;1994/Mini:9, Working paper, 1994)Information on migration pattern and swimming behaviour of pelagic fish schools in the vicinity of steaming survey vessels has been collected by a multi-beam sonar system connected to an external device for data collection ... -
On the shape, size and density of North Sea herring schools as mapped by echo integration and accurate sonar projection
(ICES CM Documents;1993/B:16, Working paper, 1993)The shape and horizontal extent of herring schools in the North Sea have been mapped by a naval sonar (SIMRAD SA 950) with narrow horizontal beam width. The density of schools that were passed over was measured by the ... -
Piscivorous fish patrol krill swarms
(Journal article; Peer reviewed, 2005-09-01)Dense swarms of the krill Meganyctiphanes norvegica in the Norwegian Sea were patrolled by large, piscivorous fish, which apparently use the krill swarms as feeding grounds in their hunt for planktivores. For the krill, ... -
Relationships between the geometric dimensions and biomass of schools
(ICES CM Documents;1990/B:41, Working paper, 1990)Acoustic measurements of the geometric dimensions and packing density of herring, sprat and saithe schools have been conducted by multi-beam sonars and echo integrator systems. Relationships between the reflected echo ... -
School geometry measurements using a sonar accuracy and an algorithm for school detection
(ICES CM Documents;1991/B:36, Working paper, 1991)The accuracy of geometric measurements of schools, using horizontal guided single-beam or multi-beam sonar, is simulated. For both types of sonars, the accuracy is dependent of horizontal beam-width and range. As multiple ... -
Schooling-by-size in the Barents Sea capelin stock
(ICES CM Documents;1990/D:28, Working paper, 1990)This paper analyses the biological samples of capelin taken by the Institute of Marine Research, Bergen, on annual stock assesment surveys in the Barents Sea from 1972 to 1989. The dependency between mean length of ... -
The challenge of the herring in the Norwegian Sea: making optimal collective spatial decision
(ICES CM Documents;1996/H:15, Working paper, 1996)Herring are long-lived multiple spawners exhibiting strong variation in reproductive and recruitment success between years. They tend to adopt low-risk, preferred-conservative strategies; for example, shifts to alternative ...