dc.contributor.author | Aglen, Asgeir | |
dc.contributor.author | Engås, Arill | |
dc.contributor.author | Huse, Irene | |
dc.contributor.author | Michalsen, Kathrine | |
dc.contributor.author | Stensholt, Boonchai K. | |
dc.date.accessioned | 2008-07-24T11:35:12Z | |
dc.date.issued | 1997 | |
dc.identifier.isbn | 5-86349-048-9 | |
dc.identifier.uri | http://hdl.handle.net/11250/107467 | |
dc.description | Gear selection and sampling gears. Proceedings of the seventh IMR-PINRO Symposium. Murmansk, 23-24 June 1997. | en |
dc.description.abstract | 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. | en |
dc.format.extent | 9888538 bytes | |
dc.format.mimetype | application/pdf | |
dc.language.iso | eng | en |
dc.publisher | PINRO Press | |
dc.relation.ispartofseries | PINRO-IMR Symposium | en |
dc.relation.ispartofseries | 7 | en |
dc.title | Vertical distribution of cod, haddock and redfish; impact on bottom trawl and acoustic surveys in the Barents Sea | en |
dc.type | Conference object | en |
dc.subject.nsi | VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fisheries technology: 924 | |
dc.source.pagenumber | s. 77-92 | |