Blar i ICES CM documents authored by IMR scientists (1949-2011) på forfatter "Nakken, Odd"
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Maturation in North-East-Arctic Haddock.
Eikeseth, Helen; Nakken, Odd (ICES CM documents, Working paper, 1999)Maturation in north-east-arctic haddock was studied in relation to fish age; length, weight and condition factor using data from scientific surveys in 1989-1998. In order to investigate the reliability of the maturity ... -
Monitoring ecosystems using research surveys: Maximizing information and minimizing cost
Nakken, Odd; Pennington, Michael (ICES CM documents, Working paper, 2001)Indices or estimates of abundance generated by research vessel surveys are becoming ever more important for assessing marine resources. Most often survey abundance indices are used in conjunction with commercial catch data ... -
Monitoring ecosystems using research surveys; maximizing information and minimizing cost
Nakken, Odd; Pennington, Michael (ICES CM Documents;2002/J:5, Working paper, 2002)Indices or estimates of abundance generated by research vessel surveys are becoming ever more important for assessing marine resources. Most often survey abundance indices are used in conjunction with commercial catch data ... -
Mortality of herring during the larval stage
Dragesund, Olav; Nakken, Odd (ICES CM Documents;1968/Sy:4, Working paper, 1968) -
Norwegian combined acoustic and bottom trawl surveys for demersal fish in the Barents Sea during winter
Jakobsen, Tore; Korsbrekke, Knut; Mehl, Sigbjørn; Nakken, Odd (ICES CM documents, Working paper, 1997)A combined acoustic and bottom trawl survey for demersal fish in the Barents Sea has been conducted annually since 1981. The main aim is to map the spatial distribution and obtain indices of abundance (numbers at age) ... -
Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1982
Dalen, John; Hylen, Arvid; Nakken, Odd; Randa, Kjell; Smedstad, Odd M. (ICES CM documents, Working paper, 1982)An acoustic survey and a bottom trawl survey were carried out in the Barents Sea during winter 1982. Both surveys showed that there has been a reduction in the total number of cod of about 50% and about 75% for haddock in ... -
On acoustic identification, sizing and abundance estimation of fish
Nakken, Odd; Midttun, Lars (ICES CM documents, Working paper, 1970) -
On the application of the echointegration method
Dalen, John; Nakken, Odd (ICES CM documents;1983/B:19, Working paper, 1983)The echo integration method used by the Institute of Marine Research is described. The model which are used to convert acoustic abundance indices into fish densities using length and species dependant conversion factors, ... -
On the geographical distribution of arctic cod in relation to the distribution of bottom temperatures in the Barents Sea, 1977-1984
Nakken, Odd; Raknes, Askjell (ICES CM documents, Working paper, 1984)The results from acoustic-trawl surveys in January-March were analysed together with observations of bottom temperatures at the same cruises. Distributions of fish abundance for each age group of cod on temperature were ... -
On the problem of determining the relationship between integrated echo intensity and fish density
Nakken, Odd (ICES CM documents, Working paper, 1975) -
On the relation between ‘true’ numbers of Northeast Arctic cod and VPA- or survey-based abundance estimates
Nakken, Odd; Pennington, Michael (ICES CM documents, Working paper, 2001)When assessing Northeast Arctic cod it is assumed that the estimates of numbers at age generated by a converged VPA type analysis are equal, on average, to the true numbers at age. Based on fishery independent survey ... -
Preliminary report of the Norwegian investigations on young cod and haddock in the Barents Sea
Nakken, Odd; Hylen, Arvid; Jakobsen, Tore; Nedreaas, Kjell Harald (ICES CM documents, Working paper, 1986)An acoustic survey and a bottom trawl survey for cod and haddock were carried out in the Barents Sea during the winter 1986. As a result of strong improvement in the recruitment for both species, most of the echo abundance ... -
Preliminary report of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1982
Nakken, Odd; Dalen, John; Hylen, Arvid; Randa, Kjell; Smedstad, Odd M. (ICES CM documents, Working paper, 1983)An acoustic survey and a bottow trawl survey for cod and haddock were carried out in the Barents Sea during the winter 1983. The two surveys gave different results. The acoustic survey showed a 50 % reduction from 1982 for ... -
Preliminary report of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1985
Nakken, Odd; Hylen, Arvid; Sunnanå, Knut; Jakobsen, Tore (ICES CM documents, Working paper, 1985)An acoustic survey and a bottom trawl survey for cod and haddock were carried out in the Barents Sea during the winter 1985. The acoustic data and the biological data from trawl stations were combined in two different ways, ... -
Preliminary reports of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1984
Nakken, Odd; Dalen, John; Hylen, Arvid; Randa, Kjell; Jakobsen, Tore (ICES CM documents, Working paper, 1984)An acoustic survey and a bottom trawl survey for cod and haddock were carried out in the Barents Sea during the winter 1984. The two surveys gave different results, both in absolute terms and when changes from the 1983 ... -
A regression model for recruitment of 3-year-old NEA cod based on capelin biomass, survey index and climate
Stiansen, Jan Erik; Aglen, Asgeir; Bogstad, Bjarte; Mehl, Sigbjørn; Nakken, Odd (Working paper, 2003) -
Relationship of parent stock size and year-class strength in Norwegian spring spawning herring
Dragesund, Olav; Nakken, Odd (ICES CM Documents;1970/Sy:20, Working paper, 1970) -
Spatial distribution of variables in marine environmental and fisheries research Part II: Distribution and length of 0-group fish in relation to environmental factors
Stensholt, Boonchai K.; Nakken, Odd (ICES CM documents, Working paper, 1998)Each year in August-September joint Norwegian-Russian 0-group surveys are carried out in the Barents Sea and adjacent waters. Based on data from these surveys, the ambient temperature and salinity for several species were ... -
Stock size of north-east arctic cod estimated from acoustic survey data 1982
Nakken, Odd; Hylen, Arvid (ICES CM documents, Working paper, 1982)Assessments of the total stock and spawning stock of North East Arctic cod were carried out on the basis of Norwegian survey data and commercial landings. The total stock, i.e. fish which was 3 years old and older at 1 ... -
Stock size of north-east arctic cod, estimates from survey data 1982/83
Nakken, Odd; Hylen, Arvid (ICES CM documents, Working paper, 1983)Assessments of the total stock and spawning stock sizes of North-East Arctic cod were carried out on the basis of Norwegian survey data and commercial landings. The total stock at 1 January 1983, fish which was 2 years old ...