Variation in acoustically measured abundance from repeated surveys of herring
A large concentration of wintering herring was surveys continuously with acoustics over 37 hours in a fjord in Northern Norway. 16 surveys of the same area were conducted. Total abundance and statistics were computed for each survey. Distribution graphs showd a clear diel variation, with deep daytim...
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1998
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ftimr:oai:imr.brage.unit.no:11250/100145 2023-05-15T17:43:23+02:00 Variation in acoustically measured abundance from repeated surveys of herring Huse, Ingvar Ostrowski, Marek 1998 1405891 bytes application/pdf http://hdl.handle.net/11250/100145 eng eng ICES CM documents 1998/J:18 http://hdl.handle.net/11250/100145 8 s. VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Working paper 1998 ftimr 2021-09-23T20:15:42Z A large concentration of wintering herring was surveys continuously with acoustics over 37 hours in a fjord in Northern Norway. 16 surveys of the same area were conducted. Total abundance and statistics were computed for each survey. Distribution graphs showd a clear diel variation, with deep daytime layers and more shallow night time distribution. Acoustically measured abundance at night was 50% of the daytime values. The results are discussed in terms of behaviour induced diel variation in acoustic backscattering, and potential influence on acoustic abundance measurements. Report Northern Norway Institute for Marine Research: Brage IMR Norway |
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Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 |
spellingShingle |
VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Huse, Ingvar Ostrowski, Marek Variation in acoustically measured abundance from repeated surveys of herring |
topic_facet |
VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 |
description |
A large concentration of wintering herring was surveys continuously with acoustics over 37 hours in a fjord in Northern Norway. 16 surveys of the same area were conducted. Total abundance and statistics were computed for each survey. Distribution graphs showd a clear diel variation, with deep daytime layers and more shallow night time distribution. Acoustically measured abundance at night was 50% of the daytime values. The results are discussed in terms of behaviour induced diel variation in acoustic backscattering, and potential influence on acoustic abundance measurements. |
format |
Report |
author |
Huse, Ingvar Ostrowski, Marek |
author_facet |
Huse, Ingvar Ostrowski, Marek |
author_sort |
Huse, Ingvar |
title |
Variation in acoustically measured abundance from repeated surveys of herring |
title_short |
Variation in acoustically measured abundance from repeated surveys of herring |
title_full |
Variation in acoustically measured abundance from repeated surveys of herring |
title_fullStr |
Variation in acoustically measured abundance from repeated surveys of herring |
title_full_unstemmed |
Variation in acoustically measured abundance from repeated surveys of herring |
title_sort |
variation in acoustically measured abundance from repeated surveys of herring |
publishDate |
1998 |
url |
http://hdl.handle.net/11250/100145 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Northern Norway |
genre_facet |
Northern Norway |
op_source |
8 s. |
op_relation |
ICES CM documents 1998/J:18 http://hdl.handle.net/11250/100145 |
_version_ |
1766145433608912896 |