Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea
Gear selection and sampling gears. Proceedings of the seventh IMR-PINRO Symposium. Murmansk, 23-24 June 1997. At a selected location in the Barents Sea acoustic observations, bottom- and pelagic trawl catch data were collected over a 10 day period. A large proportion of the fish were in the acoustic...
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ftimr:oai:imr.brage.unit.no:11250/107467 2023-05-15T15:38:43+02:00 Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea Aglen, Asgeir Engås, Arill Huse, Irene Michalsen, Kathrine Stensholt, Boonchai K. 1997 9888538 bytes application/pdf http://hdl.handle.net/11250/107467 eng eng PINRO Press PINRO-IMR Symposium 7 urn:isbn:5-86349-048-9 http://hdl.handle.net/11250/107467 s. 77-92 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fisheries technology: 924 Conference object 1997 ftimr 2021-09-23T20:16:17Z Gear selection and sampling gears. Proceedings of the seventh IMR-PINRO Symposium. Murmansk, 23-24 June 1997. At a selected location in the Barents Sea acoustic observations, bottom- and pelagic trawl catch data were collected over a 10 day period. A large proportion of the fish were in the acoustic dead zone during the sampling period. Only during a few hours in the daytime high acoustic values were obtained. According to the pelagic trawl hauls these recordings consisted of large haddock ascending from the bottom, while small haddock and small redfish dominated the acoustic recordings at night. The bottom trawl catches showed higher variability and higher average catch rates during the day than at night, but the diurnal variations were relatively less pronounced than those of the acoustic recordings. The largest reduction in catch rates from day to night was observed for small haddock and redfish. This is consistent with the observation that these were found pelagicly during night. The acoustic observations and the bottom trawl catch rates were found to be correlated with diurnal cycles in observed light level and semidiurnal cycles in current speed. The results are interpreted in terms of variable catchability of the bottom trawl and variable availability for the echo sounder. Conference Object Barents Sea Institute for Marine Research: Brage IMR Barents Sea Murmansk |
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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::Fisheries technology: 924 |
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VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fisheries technology: 924 Aglen, Asgeir Engås, Arill Huse, Irene Michalsen, Kathrine Stensholt, Boonchai K. Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea |
topic_facet |
VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fisheries technology: 924 |
description |
Gear selection and sampling gears. Proceedings of the seventh IMR-PINRO Symposium. Murmansk, 23-24 June 1997. At a selected location in the Barents Sea acoustic observations, bottom- and pelagic trawl catch data were collected over a 10 day period. A large proportion of the fish were in the acoustic dead zone during the sampling period. Only during a few hours in the daytime high acoustic values were obtained. According to the pelagic trawl hauls these recordings consisted of large haddock ascending from the bottom, while small haddock and small redfish dominated the acoustic recordings at night. The bottom trawl catches showed higher variability and higher average catch rates during the day than at night, but the diurnal variations were relatively less pronounced than those of the acoustic recordings. The largest reduction in catch rates from day to night was observed for small haddock and redfish. This is consistent with the observation that these were found pelagicly during night. The acoustic observations and the bottom trawl catch rates were found to be correlated with diurnal cycles in observed light level and semidiurnal cycles in current speed. The results are interpreted in terms of variable catchability of the bottom trawl and variable availability for the echo sounder. |
format |
Conference Object |
author |
Aglen, Asgeir Engås, Arill Huse, Irene Michalsen, Kathrine Stensholt, Boonchai K. |
author_facet |
Aglen, Asgeir Engås, Arill Huse, Irene Michalsen, Kathrine Stensholt, Boonchai K. |
author_sort |
Aglen, Asgeir |
title |
Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea |
title_short |
Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea |
title_full |
Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea |
title_fullStr |
Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea |
title_full_unstemmed |
Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea |
title_sort |
vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the barents sea |
publisher |
PINRO Press |
publishDate |
1997 |
url |
http://hdl.handle.net/11250/107467 |
geographic |
Barents Sea Murmansk |
geographic_facet |
Barents Sea Murmansk |
genre |
Barents Sea |
genre_facet |
Barents Sea |
op_source |
s. 77-92 |
op_relation |
PINRO-IMR Symposium 7 urn:isbn:5-86349-048-9 http://hdl.handle.net/11250/107467 |
_version_ |
1766369987234103296 |