Blar i Articles på emneord "VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fisheries technology: 924"
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Abundance estimation of Northeast Atlantic mackerel based on tag recapture data - A useful tool for stock assessment?
(Journal article; Peer reviewed, 2010-10)In the present study we utilize tag recapture data to estimate year class abundance and spawning stock biomass of mackerel (Scomber scombrus L.) in the Northeast Atlantic for the period 1986–2008. On average 20,000 jigged ... -
Accuracy of the Kirchhoff-Approximation and Kirchhoff-Ray-Mode Fish Swimbladder Acoustic Scattering Models
(Journal article; Peer reviewed, 2013-05-14)The acoustic backscatter from pressure release prolate spheroids and a three-dimensional representation of a fish swimbladder (Chilean jack mackerel, Trachurus symmetricus murphyi) was calculated using four target strength ... -
Accuracy of VMS data from Norwegian demersal stern trawlers for estimating trawled areas in the Barents Sea
(Journal article; Peer reviewed, 2011-06-08)The accuracy of vessel monitoring system (VMS) data, used to determine fishing activity in the trawl fishery for gadoids in the Barents Sea, was studied by observer notes and Global Positioning System (GPS) data from two ... -
Behavioral responses of herring (Clupea harengus) to 1–2 and 6–7 kHz sonar signals and killer whale feeding sounds
(Journal article; Peer reviewed, 2009-01)Military antisubmarine sonars produce intense sounds within the hearing range of most clupeid fish. The behavioral reactions of overwintering herring (Clupea harengus) to sonar signals of two different frequency ranges ... -
Best practices to mitigate seabird bycatch in longline, trawl and gillnet fisheries—efficiency and practical applicability
(Journal article; Peer reviewed, 2011-08-22)Growing concerns have been raised about incidental capture of seabirds in various fisheries. Here, studies testing measures to prevent seabird bycatch in longline, trawl and gillnet fisheries are reviewed in order to ... -
Catchability of pelagic trawls for sampling deep-living nekton in the mid-North Atlantic
(Journal article; Peer reviewed, 2010-06-29)Material collected in summer 2004 from the Mid-Atlantic Ridge between Iceland and the Azores with three pelagic trawls was used to estimate relative catchabilities of common fish, cephalopod, decapod, and jellyfish species. ... -
The combined impact of plant-derived dietary ingredients and acute stress on the intestinal arachidonic acid cascade in Atlantic salmon (Salmo salar)
(Journal article; Peer reviewed, 2010-03)A study was conducted to assess the effect of substituting high levels of dietary fish oil (FO) and fishmeal (FM) for vegetable oil (VO) and plant protein (PP) on the intestinal arachidonic acid (AA) cascade in the carnivorous ... -
Day and night fish distribution pattern in the net mouth area of the Norwegian bottom-sampling trawl
(Journal article; Peer reviewed, 1990)A high-frequency scanning sonar, mounted as a net sonde, was used to study fish behaviour in the mouth area of the Norwegian bottom-sampling trawl. Fish distribution patterns were significantly different by day and night. ... -
Detecting Atlantic herring by parametric sonar
(Journal article; Peer reviewed, 2010-03-17)The difference-frequency band of the Kongsberg TOPAS PS18 parametric sub-bottom profiling sonar, nominally 1–6 kHz, is being used to observe Atlantic herring. Representative TOPAS echograms of herring layers and schools ... -
Development of eleven microsatellite loci in the deep-sea black scabbardfish (Aphanopus carbo)
(Journal article; Peer reviewed, 2009-06)We developed 11 microsatellite loci primers in the bathypelagic black scabbardfish (Aphanopus carbo), a novelty for deep-sea fishes. All markers were obtained from partial genomic DNA libraries enriched for tetranucleotide ... -
Development of ten microsatellite loci in the marine fish ling (Molva molva)
(Journal article; Peer reviewed, 2009-09)We developed primers for two dinucleotide and eight tetranucleotide microsatellite loci in a marine fish, the ling (Molva molva). All markers were obtained from partial genomic DNA libraries and characterized in 55 unrelated ... -
Estimating tail-beat frequency using split-beam echosounders
(Journal article; Peer reviewed, 2009-02-04)Data from a standard split-beam echosounder are used to estimate tail-beat frequency within a dense herring (Clupea harengus L.) layer. The data were collected by lowering a horizontally projecting 38 kHz split-beam ... -
Fish avoidance of research vessels and the efficacy of noise-reduced vessels: a review
(Journal article; Peer reviewed, 2012-10-19)It has long been recognized that fish can avoid approaching vessels and that these behaviours can bias fishery surveys. Underwater noise is considered the primary stimulus, and standards for research vessel noise have been ... -
Lateral-aspect target strength measurements of in situ herring (Clupea harengus)
(Journal article; Peer reviewed, 2009-07)Surveys of schooling herring with the new multi-beam sonar (Simrad MS70) pose new challenges when converting the echo energy to estimates of biomass. Since the sonar projects horizontally, data and models of lateral-aspect ... -
Observations of cod reaction to trawling noise
(Working paper, 1988-04)Observations made from a stationary echo sounder, passed by a trawling vessel, clearly demonstrate the flight reaction of cod as a response to the noise from the vessel. Horizontal dispersal and downward swimming has been ... -
Observing the behavioral response of herring exposed to mid-frequency sonar signals. (A)
(Conference object, 2010-03)There is general concern on how mid-frequency military sonars might affect aquatic animals. Approaches used to investigate possible effects on Norwegian spring spawning herring (Clupea harengus) are presented. Experiments ... -
Simulations of multi-beam sonar echos from schooling individual fish in a quiet environment
(Journal article; Peer reviewed, 2012-12)A model is developed and demonstrated for simulating echosounder and sonar observations of fish schools with specified shapes and composed of individuals having specified target strengths and behaviors. The model emulates ... -
Size Selection of Antarctic Krill (Euphausia superba) in Trawls
(Journal article; Peer reviewed, 2014-08-08)Trawlers involved in the Antarctic krill (Euphausia superba) fishery use different trawl designs, and very little is known about the size selectivity of the various gears. Size selectivity quantifies a given trawl’s ability ... -
Stereological calibration of the profile method to quickly estimate atresia levels in fish
(Journal article; Peer reviewed, 2010-05)The (physical) ‘disector method’, a frequently cited stereological technique, has so far received little attention within fish fecundity studies, although it can be used to provide unbiased, assumption-free data on levels ... -
Thermal niche of Atlantic cod Gadus morhua: limits, tolerance and optima
(Journal article; Peer reviewed, 2010)Recent studies in the marine environment have suggested that the limited phenotypic plasticity of cold-adapted species such as Atlantic cod Gadus morhua L. will cause distributions to shift toward the poles in response to ...