Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock
A full-scale fishing experiment on north-east Arctic cod ( Gadus morhua ) and haddock ( Melanogrammus aeglefinus ), involving a trawler, a longliner and a gillnetter was conducted in order to determine how the length distributions and life history parameters of the catches were affected by gear type...
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fthighwire:oai:open-archive.highwire.org:icesjms:57/4/1271 2023-05-15T14:30:32+02:00 Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock Huse, Irene Løkkeborg, Svein Soldal, Aud Vold 2000-08-01 00:00:00.0 text/html http://icesjms.oxfordjournals.org/cgi/content/short/57/4/1271 https://doi.org/10.1006/jmsc.2000.0813 en eng Oxford University Press http://icesjms.oxfordjournals.org/cgi/content/short/57/4/1271 http://dx.doi.org/10.1006/jmsc.2000.0813 Copyright (C) 2000, International Council for the Exploration of the Sea/Conseil International pour l'Exploration de la Mer Articles TEXT 2000 fthighwire https://doi.org/10.1006/jmsc.2000.0813 2013-05-27T04:57:43Z A full-scale fishing experiment on north-east Arctic cod ( Gadus morhua ) and haddock ( Melanogrammus aeglefinus ), involving a trawler, a longliner and a gillnetter was conducted in order to determine how the length distributions and life history parameters of the catches were affected by gear type. Relative selectivity was analysed for catches taken when the boats fished simultaneously in the same area, and when the skippers were allowed to fish under conditions as close as possible to commercial operation. Trawl and longline-caught cod had similar length distributions, but cod caught by trawl were on average 2.3 cm smaller than longline-caught cod. Cod caught by longline had a lower condition factor and length at age. The longliner caught smaller haddock than the trawler when the boats fished in the same area. When the skippers were allowed to change fishing ground, the mean length of cod increased in the trawl catches and became larger than the mean length in the longline catches. The mean length of haddock in the longline catches increased by 2.8 cm and became larger than that of the trawl catches. Gillnet catches consisted almost solely of large cod. Mean length of gillnet caught fish in 186 mm nets decreased from 86.2 cm to 82.3 cm even if the boat did not change area. Separate selectivity experiments for trawl and gillnet were conducted, and the parameters for the mesh selection are presented. To find the functional form of the longline selectivity we used relative catch proportion in each 5 cm length-group for longline compared to trawl and gillnet, whose selectivities were assumed to be known. When compared to that of the gillnet, the plots indicate that the longline selectivity curve takes the form of a unimodal distribution. When longline catches was compared to trawl catches none of the suggested models seemed to fit, and to conclude anything about the form of the longline selection curve is not possible. Text Arctic cod Arctic Gadus morhua HighWire Press (Stanford University) Arctic Fishing Ground ENVELOPE(-55.848,-55.848,49.550,49.550) ICES Journal of Marine Science 57 4 1271 1282 |
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HighWire Press (Stanford University) |
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Articles Huse, Irene Løkkeborg, Svein Soldal, Aud Vold Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock |
topic_facet |
Articles |
description |
A full-scale fishing experiment on north-east Arctic cod ( Gadus morhua ) and haddock ( Melanogrammus aeglefinus ), involving a trawler, a longliner and a gillnetter was conducted in order to determine how the length distributions and life history parameters of the catches were affected by gear type. Relative selectivity was analysed for catches taken when the boats fished simultaneously in the same area, and when the skippers were allowed to fish under conditions as close as possible to commercial operation. Trawl and longline-caught cod had similar length distributions, but cod caught by trawl were on average 2.3 cm smaller than longline-caught cod. Cod caught by longline had a lower condition factor and length at age. The longliner caught smaller haddock than the trawler when the boats fished in the same area. When the skippers were allowed to change fishing ground, the mean length of cod increased in the trawl catches and became larger than the mean length in the longline catches. The mean length of haddock in the longline catches increased by 2.8 cm and became larger than that of the trawl catches. Gillnet catches consisted almost solely of large cod. Mean length of gillnet caught fish in 186 mm nets decreased from 86.2 cm to 82.3 cm even if the boat did not change area. Separate selectivity experiments for trawl and gillnet were conducted, and the parameters for the mesh selection are presented. To find the functional form of the longline selectivity we used relative catch proportion in each 5 cm length-group for longline compared to trawl and gillnet, whose selectivities were assumed to be known. When compared to that of the gillnet, the plots indicate that the longline selectivity curve takes the form of a unimodal distribution. When longline catches was compared to trawl catches none of the suggested models seemed to fit, and to conclude anything about the form of the longline selection curve is not possible. |
format |
Text |
author |
Huse, Irene Løkkeborg, Svein Soldal, Aud Vold |
author_facet |
Huse, Irene Løkkeborg, Svein Soldal, Aud Vold |
author_sort |
Huse, Irene |
title |
Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock |
title_short |
Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock |
title_full |
Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock |
title_fullStr |
Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock |
title_full_unstemmed |
Relative selectivity in trawl, longline and gillnet fisheries for cod and haddock |
title_sort |
relative selectivity in trawl, longline and gillnet fisheries for cod and haddock |
publisher |
Oxford University Press |
publishDate |
2000 |
url |
http://icesjms.oxfordjournals.org/cgi/content/short/57/4/1271 https://doi.org/10.1006/jmsc.2000.0813 |
long_lat |
ENVELOPE(-55.848,-55.848,49.550,49.550) |
geographic |
Arctic Fishing Ground |
geographic_facet |
Arctic Fishing Ground |
genre |
Arctic cod Arctic Gadus morhua |
genre_facet |
Arctic cod Arctic Gadus morhua |
op_relation |
http://icesjms.oxfordjournals.org/cgi/content/short/57/4/1271 http://dx.doi.org/10.1006/jmsc.2000.0813 |
op_rights |
Copyright (C) 2000, International Council for the Exploration of the Sea/Conseil International pour l'Exploration de la Mer |
op_doi |
https://doi.org/10.1006/jmsc.2000.0813 |
container_title |
ICES Journal of Marine Science |
container_volume |
57 |
container_issue |
4 |
container_start_page |
1271 |
op_container_end_page |
1282 |
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1766304364322881536 |