Browsing Brage IMR by Subject "VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ethology: 485"
Now showing items 41-60 of 180
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Dynamics of wintering Norwegian spring-spawning herring at the entrance to Tysfjorden, December 1996
(ICES CM Documents;1997/CC:16, Working paper, 1997)The entrance region to Tysfjorden was acoustically surveyed a total of eleven times during the December 1996 abundance survey of the spawning stock of Norwegian spring-spawning herring (Clupea harengus). The observations ... -
Effect of swimming on fish target strength
(ICES CM Documents;1985/B:29, Working paper, 1985)The influence of the swimming movement on fish target strength is investigated through a modelling exercise. In this, several gadoid specimens are represented as acoustic scatterers through their triangulated swimbladder ... -
Effects of pre-release acclimatization period on salmon return rates
(ICES CM Documents;1995/M:13, Working paper, 1995)42.000 1+smolts of Atlantic salmon were size graded into two size groups and released during three weeks in spring 1993; one group of small and one of large smolts on each of the four release days. Approximately 25% of ... -
Effects on salmon (Salmo salar) from different operational procedures in fish farming
(ICES CM Documents;1988/F:16, Working paper, 1988)The effects on farmed salmon caused by operational procedures as handling, de-lousing, removal of dead fish, grading and transfer were studied by underwater TV-observations, ultrasonic telemetry of heart rate and analyses ... -
Engineering and fish reaction aspects of gillnetting - a review
(ICES CM Documents;1981/B:34, Working paper, 1981) -
Engineering and fish reaction aspects of longlining - A review
(ICES CM Documents;1981/B:35, Working paper, 1981) -
Environmental influences on the recruitment process inferred from otolith stable isotopes in Merluccius merluccius off the Balearic Islands
(Journal article; Peer reviewed, 2008-08-13)Oxygen (δ18O) and carbon (δ13C) isotope ratios in sagittal otoliths were analysed in recruits and juveniles of European hake Merluccius merluccius L. caught in the northwest (Sóller, SO) and south (Cabrera, CA) of the ... -
Extensive gas bubble release in Norwegian spring spawning herring (Clupea harengus) during predator avoidance
(ICES CM Documents;1998/J:20, Working paper, 1998)Events of extensive gas bubble releases in overwintering Norwegian spring spawning herring (Clupea harengus) were repeatedly observed acoustically and visually in Vestfjorden, northem Norway, during attacks from killer ... -
Feeding and migration of Norwegian spring spawning herring in the Norwegian Sea
(ICES CM Documents;1994/R:9, Working paper, 1994)After spawning on the shelf off Møre, Western Norway, the spawning stock of Norwegian spring spawning herring migrates to the Norwegian Sea for feeding. Simultaneously, the adolescent part of the stock leaves the wintering ... -
Field methods for fish behaviour studies used in Norway
(PINRO-IMR Symposium, Conference object, 1997) -
Fish distribution studies around offshore installations
(ICES CM Documents;1977/B:41, Working paper, 1977) -
Fjordranching with conditioned cod
(ICES CM Documents;1987/F:29, Working paper, 1987)In June 1986, 1600 pond-reared one-year old cod were released into a fjord after being conditioned with a pulsed 160 Hz sound signal to search for food at a feeding location. Echosounders, UW-video and ultrasonic ... -
Food and feeding conditions of herring Clupea harengus in the Norwegian Sea
(ICES CM Documents;1996/L:20, Working paper, 1996)The feeding ecology of herring was studied using samples collected during cruises in 1994 and 1995. Investigations were carried out in the Møre shelf region off western Norway where the major spawning of herring occurs, ... -
Food and feeding habits of young saithe (Pollachius virens L.) on the coast of western Norway
(ICES CM Documents;1985/G:22, Working paper, 1985)The stomach contents of young saithe [Pollachius virens (L. )] (I- and II-group, mainly II-group) in two areas (A and B) on the western coast of Norway, has been analysed. When this juvenile saithe become two or mainly ... -
Foraging behaviour of larval cod (Gadus morhua) at low light intensities
(Journal article; Peer reviewed, 2011-02-13)The ability to forage at low light intensities can be of great importance for the survival of fish larvae in a pelagic environment. Three-dimensional silhouette imaging was used to observe larval cod foraging and swimming ... -
Foraging behaviour of larval cod (Gadus morhua) at low light intensities
(Journal article; Peer reviewed, 2011-02-13)The ability to forage at low light intensities can be of great importance for the survival of fish larvae in a pelagic environment. Three-dimensional silhouette imaging was used to observe larval cod foraging and swimming ... -
Grid-sorting of penned saithe
(ICES CM Documents;1992/B:11, Working paper, 1992)Size selection of penned saithe was obtained by forcing the fish against an adjustable grid mounted in the end of net pens. The size selection was rather sharp, with a selection range of about 5 cm only. All fish forced ... -
Habitat choice by marine zooplankton in a high-latitude ecosystem
(Journal article; Peer reviewed, 2008-07-29)According to habitat choice theory, zooplanktonic prey should choose a depth habitat that maximizes food intake while minimizing predation risk. Body size affects competitive ability and vulnerability in zooplankton, ... -
Haddock avoidance reactions during trawling
(ICES CM Documents;1986/B:36, Working paper, 1986)Fish reaction to the whole trawling operation was studied using a stationary echo sounder-system observing the fish in front of the vessel and during trawl passage. Strong avoidance reactions were observed on haddock, ... -
Halibut behaviour as a means of assessing suitability of ongrowth systems
(ICES CM Documents;1998/L:4, Working paper, 1998)Halibut behaviour in net pens has been studied using direct observation, underwater video and/or hydroacoustic equipment. Rearing experience includes a wide range of fish weights (50-10.000 g) and fish densities (4-150 ...