Blar i Brage IMR på emneord "VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fisheries technology: 924"
Viser treff 41-60 av 725
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Assessing the effect of intra-haul correlation and variable density on population estimates from marine surveys
(ICES CM Documents;1991/D:14, Working paper, 1991)In a previous paper (Pennington and Vølstad, Biometrics 47, 1991) it was suggested that reducing the size of the sampling unit generally used in marine surveys could increase the precision of abundance estimates. But if ... -
Assessing trawl-survey estimates of frequency distributions
(ICES CM Documents;2000/K:23, Working paper, 2000)Marine trawl surveys catch a cluster of fish at each station and fish caught together tend to have more similar characteristics, such as length, age, stomach contents etc., than those in the entire population. When this ... -
Assigning values of target strength and equivalent beam angle in acoustic surveys of fish
(ICES CM Documents;1991/B:34, Working paper, 1991)Contrary to popular opinion, the equivalent beam angle (~) is not determined solely by the transducer directivity. Rather, like the target strength TS, it also depends on the scattering properties of the target fish, but ... -
Automatic calibration of the sensors used in a miniature STD instrument
(ICES CM Documents;1988/C:13, Working paper, 1988)The paper describes a system for simplified calibration of a new STD instrument. When measuring, the raw data from the instrument conductivity, temperature and pressure sensors are fed into a microprocessor inside the ... -
Automatic recording of fish heart rate on a personal computer
(ICES CM Documents;1988/B:34, Working paper, 1988)From acoustic tags operated into fish in a closed system, the heartbeat signals are sent via underwater telemetry and counted on a personal computer. The computer removes false pulses caused by noise, and calculates the ... -
Avoidance reactions of ultrasonic tagged cod during bottom trawling in shallow water
(ICES CM Documents;1991/B:41, Working paper, 1991)Introduction: Observations made by echo sounder (Ona 1988) have shown that cod (Gadus morhua L.) may avoid an approaching survey vessel horizontally and vertically. However, there has been a lack of information on the ... -
Bad-weather calibration of split-beam echo sounder systems
(ICES CM Documents;1990/B:22, Working paper, 1990)A condition for standard-target calibration is stability of the sonar platform and target rig. This condition cannot always be met, nor need it be when the transducer has a split-beam function. Since the position of ... -
Basic studies of Norwegian longline gear
(ICES CM Documents;1976/B:27, Working paper, 1976) -
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 ... -
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 ... -
Behaviour of Atlantic salmon (Salmo salar L.) recorded by data storage tags in the NE Atlantic – implications for interception by pelagic trawls
(ICES CM documents, Working paper, 2006)In a project carried out in the Nordic Seas (Northeast Atlantic) in 2002 - 2004, 413 Atlantic salmon (Salmo salar L.) were tagged with data storage tags (DST) either logging temperature and depth (StarOddi, Milli) or ... -
Behaviour of Norwegian spring spawning herring in relation to underwater light
(ICES CM Documents;1988/B:24, Working paper, 1988)The Norwegian coastal purse seiners, with shallow nets, have experienced difficulties in catching the herring due to their natura! behaviour being located too deep during day time and toe scattered during night time. ... -
Behaviour studies on fish reaction to long lines
(ICES CM Documents;1978/B:22, Working paper, 1978)This study is a continuation of a field investigation on the behaviour of fish towards long lines, started in 1976. The present paper gives an analysis of the effect of current and time of the day on the activity of whiting ... -
Bergen Echo Integrator: An Introduction
(ICES CM Documents;1989/B:9, Working paper, 1989)The design of a new echo integrator system is outlined. The B.E.I. is based on preprocessed data from the new SIMRAD EK500 scientific acoustic measurement system. Raw data are displayed and interpreted on a graphics ... -
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 ... -
Beste praksis for slipping fra not. Utvikling av standard slippemetode for makrell og sild i fiske med not
(Rapport fra Havforskningen;6-2017, Working paper, 2017)Ved en Workshop som ble avholdt på Gardermoen desember 2014 ble fiskere, forskere og forvaltning enige om et forslag til «Beste praksis for slipping fra not», dvs. et sett av retningslinjer som skulle beskrive en god ... -
Calibration reflector
(ICES CM Documents;1989/B:4, Working paper, 1989)Calibration of scientific echo sounders and integrators entails, inter alia, measurement of the dynamic range. This can be done by repeating on-axis measurements of echoes from each of two different standard targets. ... -
Can subjective evaluation of echograms improve correlation between bottom trawl and acoustic densities?
(ICES CM documents, Working paper, 2004)Direct comparison of acoustic densities and trawl catches involves fundamental difficulties related to species and size selectivity of the trawl and efficiency of the acoustic instrumentation. In some surveys, therefore, ...