Gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet
Fishermen make repeated choices with respect to when, where, and how to catch their target species. While these targeting tactics—and the factors shaping them—are known to fishers and some experts, knowledge about them is largely informal and not well utilized for management purposes. To formalize i...
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Online Access: | https://hdl.handle.net/11250/3044047 https://doi.org/10.1093/icesjms/fsac207 |
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ftimr:oai:imr.brage.unit.no:11250/3044047 2023-05-15T15:27:36+02:00 Gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet Liu, Xiaozi Nedreaas, Kjell Harald Stockhausen, Hagen Heino, Mikko Petteri 2022 application/pdf https://hdl.handle.net/11250/3044047 https://doi.org/10.1093/icesjms/fsac207 eng eng Norges forskningsråd: 288037 Norges forskningsråd: 314248 Norges forskningsråd: 324159 Norges forskningsråd: 288192 ICES Journal of Marine Science. 2022, 79 (10), 2709-2727. urn:issn:1054-3139 https://hdl.handle.net/11250/3044047 https://doi.org/10.1093/icesjms/fsac207 cristin:2082404 2709-2727 79 ICES Journal of Marine Science 10 Peer reviewed Journal article 2022 ftimr https://doi.org/10.1093/icesjms/fsac207 2023-01-18T23:43:45Z Fishermen make repeated choices with respect to when, where, and how to catch their target species. While these targeting tactics—and the factors shaping them—are known to fishers and some experts, knowledge about them is largely informal and not well utilized for management purposes. To formalize information on targeting tactics, we propose a set of methods combining model-based classification of target species with generalized linear models. We apply these methods to Norwegian coastal fishing vessels that caught Atlantic cod (Gadus morhua) as a part of their catch portfolio in 2019. The data contains nearly 32000 fishing trips by 761 vessels. Gaussian mixture models identify eight latent targeting tactics. Cod contributes significantly to three of the tactics. The Herfindahl–Hirschman Index, a measure of vessel-level diversity of tactics, shows that one quarter of the vessels had a specialized strategy (targeting cod plus at most one additional tactic). While cod is often studied as a single-species fishery, we show that cod-catching vessels can be engaged in relatively pure fisheries during some fishing trips but switch to different, often more mixed targets during other trips. We term this as “sequential mixed fisheries”. This is both a challenge and an opportunity for the fisheries management. publishedVersion Article in Journal/Newspaper atlantic cod Gadus morhua Institute for Marine Research: Brage IMR ICES Journal of Marine Science 79 10 2709 2727 |
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Institute for Marine Research: Brage IMR |
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English |
description |
Fishermen make repeated choices with respect to when, where, and how to catch their target species. While these targeting tactics—and the factors shaping them—are known to fishers and some experts, knowledge about them is largely informal and not well utilized for management purposes. To formalize information on targeting tactics, we propose a set of methods combining model-based classification of target species with generalized linear models. We apply these methods to Norwegian coastal fishing vessels that caught Atlantic cod (Gadus morhua) as a part of their catch portfolio in 2019. The data contains nearly 32000 fishing trips by 761 vessels. Gaussian mixture models identify eight latent targeting tactics. Cod contributes significantly to three of the tactics. The Herfindahl–Hirschman Index, a measure of vessel-level diversity of tactics, shows that one quarter of the vessels had a specialized strategy (targeting cod plus at most one additional tactic). While cod is often studied as a single-species fishery, we show that cod-catching vessels can be engaged in relatively pure fisheries during some fishing trips but switch to different, often more mixed targets during other trips. We term this as “sequential mixed fisheries”. This is both a challenge and an opportunity for the fisheries management. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Liu, Xiaozi Nedreaas, Kjell Harald Stockhausen, Hagen Heino, Mikko Petteri |
spellingShingle |
Liu, Xiaozi Nedreaas, Kjell Harald Stockhausen, Hagen Heino, Mikko Petteri Gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet |
author_facet |
Liu, Xiaozi Nedreaas, Kjell Harald Stockhausen, Hagen Heino, Mikko Petteri |
author_sort |
Liu, Xiaozi |
title |
Gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet |
title_short |
Gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet |
title_full |
Gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet |
title_fullStr |
Gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet |
title_full_unstemmed |
Gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet |
title_sort |
gaussian mixture models reveal highly diverse targeting tactics in a coastal fishing fleet |
publishDate |
2022 |
url |
https://hdl.handle.net/11250/3044047 https://doi.org/10.1093/icesjms/fsac207 |
genre |
atlantic cod Gadus morhua |
genre_facet |
atlantic cod Gadus morhua |
op_source |
2709-2727 79 ICES Journal of Marine Science 10 |
op_relation |
Norges forskningsråd: 288037 Norges forskningsråd: 314248 Norges forskningsråd: 324159 Norges forskningsråd: 288192 ICES Journal of Marine Science. 2022, 79 (10), 2709-2727. urn:issn:1054-3139 https://hdl.handle.net/11250/3044047 https://doi.org/10.1093/icesjms/fsac207 cristin:2082404 |
op_doi |
https://doi.org/10.1093/icesjms/fsac207 |
container_title |
ICES Journal of Marine Science |
container_volume |
79 |
container_issue |
10 |
container_start_page |
2709 |
op_container_end_page |
2727 |
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1766358016956825600 |