Preliminary reports of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 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 surveys are considered. The acoustic survey showed an average 1982 year class and...
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ftimr:oai:imr.brage.unit.no:11250/100265 2023-05-15T15:38:40+02:00 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 1984 853679 bytes application/pdf http://hdl.handle.net/11250/100265 eng eng ICES ICES CM documents 1984/G:44 This report is not to be quoted without prior consultation with the General Secretary. http://hdl.handle.net/11250/100265 26 s. VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 Working paper 1984 ftimr 2021-09-23T20:15:36Z 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 surveys are considered. The acoustic survey showed an average 1982 year class and a strong 1983 yearclass of cod, which is in good agreement with previous estimates. The estimates of the year classes 1979-1981 were increased. For haddock, the acoustic survey confirmed that the year classes 1982 and 1983 are strong, and the estimates of the year classes 1980 and 1981 increased. In the bottom trawl survey, the index of year - old cod (1983 yearclass) is lower than in the acoustic survey. A decrease was observed in the indices of the 1979 year class of cod and the 1980 year class of haddock. Discrepancies with the 1983 survey results and the differences between the results from the acoustic and the bottom trawl surves are discussed. Variation in the availability of different site groups of fish for the bottom trawl is a major factor. Report Barents Sea Institute for Marine Research: Brage IMR Barents Sea |
institution |
Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 |
spellingShingle |
VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 Nakken, Odd Dalen, John Hylen, Arvid Randa, Kjell Jakobsen, Tore Preliminary reports of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1984 |
topic_facet |
VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 |
description |
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 surveys are considered. The acoustic survey showed an average 1982 year class and a strong 1983 yearclass of cod, which is in good agreement with previous estimates. The estimates of the year classes 1979-1981 were increased. For haddock, the acoustic survey confirmed that the year classes 1982 and 1983 are strong, and the estimates of the year classes 1980 and 1981 increased. In the bottom trawl survey, the index of year - old cod (1983 yearclass) is lower than in the acoustic survey. A decrease was observed in the indices of the 1979 year class of cod and the 1980 year class of haddock. Discrepancies with the 1983 survey results and the differences between the results from the acoustic and the bottom trawl surves are discussed. Variation in the availability of different site groups of fish for the bottom trawl is a major factor. |
format |
Report |
author |
Nakken, Odd Dalen, John Hylen, Arvid Randa, Kjell Jakobsen, Tore |
author_facet |
Nakken, Odd Dalen, John Hylen, Arvid Randa, Kjell Jakobsen, Tore |
author_sort |
Nakken, Odd |
title |
Preliminary reports of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1984 |
title_short |
Preliminary reports of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1984 |
title_full |
Preliminary reports of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1984 |
title_fullStr |
Preliminary reports of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1984 |
title_full_unstemmed |
Preliminary reports of the Norwegian investigations on young cod and haddock in the Barents Sea during the winter 1984 |
title_sort |
preliminary reports of the norwegian investigations on young cod and haddock in the barents sea during the winter 1984 |
publisher |
ICES |
publishDate |
1984 |
url |
http://hdl.handle.net/11250/100265 |
geographic |
Barents Sea |
geographic_facet |
Barents Sea |
genre |
Barents Sea |
genre_facet |
Barents Sea |
op_source |
26 s. |
op_relation |
ICES CM documents 1984/G:44 This report is not to be quoted without prior consultation with the General Secretary. http://hdl.handle.net/11250/100265 |
_version_ |
1766369892883234816 |