Norwegian acoustic survey of North East Arctic cod on the spawning grounds off Lofoten
An acoustic survey of the spawning stock of North East Arctic Cod off Lofoten has been performed annually in March-April since 1982. The estimates for 1985-1997 have been recalculated and mean length and weight at age are shown together with the abundance indices (both numbers and biomass). The abun...
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ftimr:oai:imr.brage.unit.no:11250/105785 2023-05-15T14:30:21+02:00 Norwegian acoustic survey of North East Arctic cod on the spawning grounds off Lofoten Korsbrekke, Knut 1997 application/pdf http://hdl.handle.net/11250/105785 eng eng ICES ICES CM Documents;1997/Y:18 This report is not to be cited without prior reference to the author http://hdl.handle.net/11250/105785 18 s. arctic cod arktisk torsk spawning areas gyteplasser acoustics akustikk stock assessment bestandsberegning VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Catch: 925 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fish health: 923 Working paper 1997 ftimr 2021-09-23T20:15:19Z An acoustic survey of the spawning stock of North East Arctic Cod off Lofoten has been performed annually in March-April since 1982. The estimates for 1985-1997 have been recalculated and mean length and weight at age are shown together with the abundance indices (both numbers and biomass). The abundance indices for each age are compared with VPA results from a reasonably converged part of the series. It is shown that the VPA tuning assumption of constant log catchability at age should not be used for this survey series. As the survey produces abundance indices for the mature part of the cod stock these indices should be corrected with proportions mature before they are used in traditional assessment methods estimating year class strength. Report Arctic cod Arctic Arktis* Lofoten Institute for Marine Research: Brage IMR Arctic Lofoten |
institution |
Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
arctic cod arktisk torsk spawning areas gyteplasser acoustics akustikk stock assessment bestandsberegning VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Catch: 925 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fish health: 923 |
spellingShingle |
arctic cod arktisk torsk spawning areas gyteplasser acoustics akustikk stock assessment bestandsberegning VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Catch: 925 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fish health: 923 Korsbrekke, Knut Norwegian acoustic survey of North East Arctic cod on the spawning grounds off Lofoten |
topic_facet |
arctic cod arktisk torsk spawning areas gyteplasser acoustics akustikk stock assessment bestandsberegning VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Catch: 925 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fish health: 923 |
description |
An acoustic survey of the spawning stock of North East Arctic Cod off Lofoten has been performed annually in March-April since 1982. The estimates for 1985-1997 have been recalculated and mean length and weight at age are shown together with the abundance indices (both numbers and biomass). The abundance indices for each age are compared with VPA results from a reasonably converged part of the series. It is shown that the VPA tuning assumption of constant log catchability at age should not be used for this survey series. As the survey produces abundance indices for the mature part of the cod stock these indices should be corrected with proportions mature before they are used in traditional assessment methods estimating year class strength. |
format |
Report |
author |
Korsbrekke, Knut |
author_facet |
Korsbrekke, Knut |
author_sort |
Korsbrekke, Knut |
title |
Norwegian acoustic survey of North East Arctic cod on the spawning grounds off Lofoten |
title_short |
Norwegian acoustic survey of North East Arctic cod on the spawning grounds off Lofoten |
title_full |
Norwegian acoustic survey of North East Arctic cod on the spawning grounds off Lofoten |
title_fullStr |
Norwegian acoustic survey of North East Arctic cod on the spawning grounds off Lofoten |
title_full_unstemmed |
Norwegian acoustic survey of North East Arctic cod on the spawning grounds off Lofoten |
title_sort |
norwegian acoustic survey of north east arctic cod on the spawning grounds off lofoten |
publisher |
ICES |
publishDate |
1997 |
url |
http://hdl.handle.net/11250/105785 |
geographic |
Arctic Lofoten |
geographic_facet |
Arctic Lofoten |
genre |
Arctic cod Arctic Arktis* Lofoten |
genre_facet |
Arctic cod Arctic Arktis* Lofoten |
op_source |
18 s. |
op_relation |
ICES CM Documents;1997/Y:18 This report is not to be cited without prior reference to the author http://hdl.handle.net/11250/105785 |
_version_ |
1766304198198034432 |