Blar i ICES CM documents authored by IMR scientists (1949-2011) på forfatter "Røttingen, Ingolf"
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A quest for management objectives – case study on the Barents Sea Capelin
Røttingen, Ingolf; Tjelmeland, Sigurd (ICES CM documents;2008/O:08, Working paper, 2008)The Barents Sea capelin is a short lived arctic pelagic species and a shared Norwegian-Russian stock. Although the management objectives for Barents Sea capelin have not been explicitly stated, the management authorities ... -
A review of the process leading to the establishment of limit and precautionary reference points for the stock of Norwegian spring spawning herring
Røttingen, Ingolf (ICES CM Documents;2000/X:8, Working paper, 2000)The Coastal State Regional Management Organisation agreed in October 1999 on a on a long time strategy for Norwegian spring spawning herring. Limit and precautionary reference points are fundamental parts of this long ... -
Abundance estimation of Norwegian spring spawning herring wintering in the Vestfjord system, December 1996
Ostrowski, Marek; Foote, Kenneth G.; Røttingen, Ingolf; Slotte, Aril (ICES CM Documents;1997/FF:13, Working paper, 1997)The spawning stock of Norwegian spawning herring has been surveyed when wintering in the Vestfjord, Tysfjord, and Ofotfjord, in northem Norway in December 1996. The basic method is that of echo integration, with compensation ... -
Acoustic abundance estimates of the Icelandic stock of capelin, October 1978 - January 1980.
Vilhjálmsson, Hjálmar; Reynisson, Páll; Hamre, Johannes; Røttingen, Ingolf (ICES CM Documents;1980/H:63, Working paper, 1980)During the period October 1978 - January 1980 several estimates of the size and yearclass composition of the Icelandic capelin stock were obtained by the acoustic method. Surveying was carried out in October 1978, ... -
Acoustic abundance estimation of the Icelandic stock of capelin : 1978-1982
Vilhjálmsson, Hjálmar; Reynisson, Páll; Hamre, Johannes; Røttingen, Ingolf (Working paper, 1982)During the period October 1978 - february 1982 several abundance estimates and yearclass composition of the Icelandic capelin stock were obtained by acoustic methods. Surveying has been carried out in July-Agust, September, ... -
Acoustic abundance estimation of the stock of Norwegian spring spawning herring, winter 1995- 1996
Foote, Kenneth G.; Ostrowski, Marek; Røttingen, Ingolf; Engås, Arill; Hansen, Kaare A.; Hauge, Kjellrun Hiis; Skeide, Roar L.; Slotte, Aril; Torgersen, Øyvind (ICES CM Documents;1996/H:33, Working paper, 1996)Standard echo integration methodology has been applied to the stock of Norwegian spring spawning herring (Clupea harengus) wintering in the Ofotfjord-Tysfjord-Vestfjord system during late autumn 1995 and early winter ... -
Acoustic abundance estimation of wintering Norwegian spring spawning herring, with emphasis on methodological aspects
Røttingen, Ingolf; Foote, Kenneth G.; Huse, Ingvar; Ona, Egil (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 assessment of Norwegian spring spawning herring in the wintering area, December 1995 and January 1995
Foote, Kenneth G.; Røttingen, Ingolf (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 ... -
The agreed recovery plan in the management of Norwegian spring-spawning herring
Røttingen, Ingolf (ICES CM documents, Working paper, 2003)In October 2001 the management agency (Coastal States) for Norwegian spring spawning herring agreed to a recovery plan which will become operative if the spawning stock falls below Bpa. The main element in this recovery ... -
Angular distribution of overwintering Norwegian spring spawning herring
Huse, Ingvar; Foote, Kenneth G.; Ona, Egil; Røttingen, Ingolf (ICES CM documents, Working paper, 1994)When plankton production drops off in the fall, adult Norwegian spring spawning herring migrate to two fiords in northern Norway with stable water masses with low temperature and predation. In the wintering areas, the ... -
Data on the 1983 year class of Norwegian spring spawning herring from the period June 1985 -August 1986
Røttingen, Ingolf (ICES CM Documents;1986/H:19, Working paper, 1986)This paper considers the distribution, growth and migration of the 1983 year class of Norwegian spring spawning herring. There are, at present, two geographical components of this year class, one component with a nursery ... -
Diet and food availability for Northeast Atlantic minke whales Balaenoptera acutorostrata
Haug, Tore; Lindstrøm, Ulf; Nilssen, Kjell Tormod; Røttingen, Ingolf; Skaug, Hans Julius (ICES CM Documents;1995/N:19, Working paper, 1995)Ecological studies of the Northeast Atlantic minke whale (Balaenoptera acutorostra) were carried out during spring (mainly April-May), summer (June-July) and autumn (AugustSeptember) in 1993 and 1994. Four small-type ... -
Distribution and migration of the 1983 year class of Norwegian spring spawning herring in the period July 1987 - August 1988
Røttingen, Ingolf (ICES CM Documents;1988/H:41, Working paper, 1988)From ao wide distribution on the Norwegian coastal banks between 65°N and 69°N in June-July 1987 the herring of this year class accumulated in an area west of the Lofoten Island in August 1987, and migrated into the ... -
Evaluation of candidate management plans, with reference to North-East Arctic Cod
Skagen, Dankert W.; Bogstad, Bjarte; Sandberg, Per; Røttingen, Ingolf (ICES CM documents, Working paper, 2003)We here discuss the scope, nature and quality standards of simulation models that may be used in order to evaluate proposed or candidate management plans, including their parameters (reference points). A recently proposed ... -
Experiences using the ES-400, split-beam echo sounder, with special reference to the single-fish recognition criterion
Ona, Egil; Røttingen, Ingolf (ICES CM Documents;1986/B:38, Working paper, 1986)Realistic estimates of in situ target strength can be made when the fish concentrations are acoustically resolved into single individuals. In the split-beam echo sounder, as in all other systems available for in situ ... -
Feeding and migration of Norwegian spring spawning herring in the Norwegian Sea
Melle, Webjørn; Røttingen, Ingolf; Skjoldal, Hein Rune (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 intercalibrations of echo integrator systems
Røttingen, Ingolf (ICES CM Documents;1978/B:25, Working paper, 1978)The paper reviews intercalibrations of echo integrators carried out in 1975 - 1977 where Norwegian research vessels have participated. Analog and digital integrator performance is compared, and methods to make integrator ... -
Herring (Clupea harengus) as a key species in northeast Atlantic mink whale (Balaenoptera acutorostrata) diets
Lindstrøm, Ulf; Haug, Tore; Røttingen, Ingolf (ICES CM documents, Working paper, 1998) -
Indication of high natural mortality for juvenile herring from acoustic and tagging data.
Røttingen, Ingolf (ICES CM Documents;1980/H:62, Working paper, 1980)Natural mortality for juvenile herring (Norwegian Spring spawners) is discussed on the basis of following data: 1. Acoustic estimates of the 1975 and 1976 yearclasses of herring as 0-group and estimates from tagging ... -
Investigations on the 1983 year-class of Norwegian spring-spawning herring
Røttingen, Ingolf (ICES CM Documents;1984/H:39, Working paper, 1984)