Blar i ICES CM documents authored by IMR scientists (1949-2011) på emneord "VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fisheries technology: 924"
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1999 ICES coordinated acoustic survey of ICES Divisions IIIa, IVa, IVb and VIa
(ICES CM Documents;2000/K:39, Working paper, 2000)Five surveys were carried out during late June and July covering most of the continental shelf north of 54°N in the North Sea and Ireland to the west of Scotland to a northern limit of 62°N. The eastern edge of the survey ... -
A field intercomparison between a miniature CTD and the Neil Brown serial 1223 CTD- profiler
(ICES CM Documents;1989/C:24, Working paper, 1989)During a survey in Lofoten in may 1989 a new miniature CTD which is being developed at the Inst. of Marine Research was mounted to the ship`s ordinary serial 1223 CTD- profiler on 10 different CTD- stations. Using the ... -
A field intercomparison between an acoustic current profiler / ADCP and two Savonius type current meters
(ICES CM Documents;1990/C:30, Working paper, 1990)During an introductory experiment in Lofoten May 1990 data from a vessel mounted ADCP on an anchored research vessel were intercompared with corresponding data from two anchored rotor current meters in a region where the ... -
A method to reduce survey bottom trawl variability
(ICES CM Documents;1991/B:39, Working paper, 1991)A technique for limiting the variability of trawl doorspread is described. In addition, modifications of trawling technique which enable the doors to stay upright and maintain constant ground contact under different ... -
A new miniature instrument for in situ measuring, processing, recording and display of oceanographic properties
(ICES CM Documents;1987/C:6, Working paper, 1987)The paper describes the design philosophy and functions of a new general purpose oceanographic instrument which is presently being tested as a prototype. The instrument combines established oceanic sensors with ... -
A new radio link telemetry positioning system, experiences from tracking of fish and crustaceans
(ICES CM Documents;1993/B:23, Working paper, 1993)Telemetry positioning systems based on hydrophone arrays have been used for different tracking applications. The main improvement of this new system is the wire-less transmission of signals from hydrophone - radio buoys ... -
A new system for automatic STD data acquisition from randomly positioned observers
(ICES CM Documents;1991/C:21, Working paper, 1991)The Inst. of Marine Researche in Bergen has since 1935 on a regulary basis acquired data from fixed hydrographic stations on the Norwegian coast. The data are collected by local residents via water samplers and reversing ... -
A PC-based echo integrator system appliable for school structure analyzis
(ICES CM Documents;1991/B:43, Working paper, 1991)A low cost system for integration of echo signals on a PC has been developed. The system calculates the area backscattering strength in surface and bottom layers, and is designed both for the purpose of conventional ... -
A preliminary Investigation on Shelf Edge and Deepwater Fixed Net Fisheries to the West and North of Great Britain, Ireland, around Rockall and Hatton Bank.
(ICES CM documents;2005/ N:07, Working paper, 2005)Since the mid-1990s, a fleet of up to 50 vessels have been conducting a gillnet fishery on the continental slopes to the West of the British Isles, North of Shetland, at Rockall and Hatton bank. These vessels, though ... -
A stripping method for Atlantic halibut (Hippoglossus hippoglossus L.)
(ICES CM Documents;1987/F:40, Working paper, 1987)A stripping-board was built and tested on a broodstock of halibut ranging from 8 to 150 kg body weight. The smooth surface of the neophrene mattress minimized the loss of mucus and reduced the stripping stress ... -
A vessel specific bias in echo sounder recordings during trawling
(ICES CM Documents;2004/R:35, Working paper, 2004) -
Absorption of acoustic energy in dense herring schools studied by the attenuation in the bottom echo signal
(ICES CM Documents;1990/B:2, Working paper, 1990)The absorption of acoustic energy in herring schools is studied by echo integration of the bottom signal under various densities of herring. The investigations were carried out in a fjord in northern Norway, where large ... -
Abundance estimation of pelagic fish stocks by acoustic surveying
(ICES CM Documents;1991/B:33, Working paper, 1991)The echo integration technique is outlined. Weaknesses are identified and remedies described. While the technique is adequate for surveying some stocks, improvements are necessary for its proper application to others. ... -
Abundance estimation of schools using a fisheries sonar
(ICES CM Documents;1991/B:35, Working paper, 1991)An attempt of abundance estimation of fish schooling close to surface using sonar was conducted in Eastern North Sea - Skagerrak in September 1990. The method is based on measurements of the school area by the Furuno ... -
Acoustic abundance estimation of wintering Norwegian spring spawning herring, with emphasis on methodological aspects
(ICES CM Documents;1994/(B+D+G+H):1, Working paper, 1994)The spawning component and part of the juvenile stock of Norwegian spring spawning herring have been wintering in a fjord system in northern Norway in recent years. Conditions for measuring the stock size have been ... -
Acoustic and Bottom Trawl Surveys; How Much Information Do They Provide for Assessing the Northeast Arctic Cod Stock?
(ICES CM documents, Working paper, 1999)Acoustic and bottom trawl surveys of the Northeast Arctic cod stock provide fishery independent estimates of trends in abundance and population characteristics. Given the recent uncertainties in the catch based assessment ... -
Acoustic assessment of Norwegian spring spawning herring in the wintering area, December 1995 and January 1995
(ICES CM Documents;1995/H:9, Working paper, 1995)The abundance of the mature component of the stock of Norwegian spring spawning herring has been estimated based on a series of echo integration surveys. These were performed in the wintering area of Ofotfjord, Tysfjord, and ... -
Acoustic backscatter from zooplankton and fish explored through an optimized model framework
(ICES CM Documents;2004/R:39, Working paper, 2004)The purpose of this work has been to test complementary methods in order to classify marine organisms, with particularly attention to zooplankton and fish. Algorithms to separate fish and zooplankton have been developed ... -
Acoustic extinction in dense herring layers, measured from a bottom-mounted transducer
(ICES CM documents, Working paper, 2006)Herring is often found in dense aggregations or schools, and acoustic shadowing is thus a problem in acoustic survey estimates. Knowledge of the attenuated echo intensity in herring aggregations is essential for correcting ... -
Acoustic measurements of schooling herring. Estimation of school biomass and target strength
(ICES CM Documents;1988/B:26, Working paper, 1988)The connections between reflected echo energy and dimensions of fatty herring schools were studied by a combination of multibeam sonar and a calibrated echo integration unit. A relation between the area and the biomass ...