Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study
The threat of population declines caused by pelagic longline fisheries in the Atlantic has increased the concern to find strategies that minimize the bycatch and mortality of non-target marine animals. Gear modification, such as the use of circle hooks instead of conventional J-hooks, has been ident...
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Online Access: | http://hdl.handle.net/10400.12/9647 https://doi.org/10.1371/journal.pone.0292727 |
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ftispalisboa:oai:repositorio.ispa.pt:10400.12/9647 2024-09-15T18:24:20+00:00 Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study Lima, Françoise Parra, Hugo Alves, Rita B. Santos, Marco A. R. Bjorndal, Karen Bolten, Alan B. Vandeperre, Frederic 2024-03-05T16:37:26Z http://hdl.handle.net/10400.12/9647 https://doi.org/10.1371/journal.pone.0292727 eng eng Public Library of Science Lima FD, Parra H, Alves RB, Santos MAR, Bjorndal KA, Bolten AB, et al. (2023) Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study. PLoS ONE 18(10): e0292727. https://doi.org/10.1371/journal. pone.0292727 19326203 http://hdl.handle.net/10400.12/9647 doi:10.1371/journal.pone.0292727 openAccess http://creativecommons.org/licenses/by/4.0/ article 2024 ftispalisboa https://doi.org/10.1371/journal.pone.029272710.1371/journal 2024-08-20T03:31:59Z The threat of population declines caused by pelagic longline fisheries in the Atlantic has increased the concern to find strategies that minimize the bycatch and mortality of non-target marine animals. Gear modification, such as the use of circle hooks instead of conventional J-hooks, has been identified as an effective bycatch reduction strategy in different pelagic longline fisheries around the world. This study aimed to verify the effectiveness of the use of circle hooks by quantifying catch rates, relative size selectivity, and anatomical hooking position for the most common target species (swordfish, Xiphias gladius, and blue shark, Prionace glauca), and some bycatch species (loggerhead sea turtles, Caretta caretta, and shortfin mako, Isurus oxyrinchus) caught by the Azorean longline fishing fleet. The trial was conducted for five consecutive years (2000–2004) using eight different types of hooks. In general, the blue shark catches using circle hooks were significantly higher compared to J (Mustad 9/0). The circle hooks also showed high probabilities of catching juvenile blue sharks. Conversely, the circle hooks were efficient in reducing the loggerhead sea turtle bycatch and were related to fewer catches of small sea turtle individuals. The use of circle hooks was also associated with reduced swordfish catches compared to J (Mustad 9/0), and the effect of hook types on length at capture was only significant for Circle (L. & P. 18/0 —CLP18) and Ringed Tuna (RT). No significant differences were observed comparing hook type to either catch rates or size selectivity for shortfin mako. Additionally, circle hooks were more likely to lodge in the mouth than in deeper anatomical positions, when compared to J (Mustad 9/0), for the four species analysed. The present study demonstrated that the use of circle hooks could mitigate the impact of the pelagic longline fisheries in the Azores by decreasing the bycatch of sea turtles and reducing animal injuries caused by deep hooking. ... Article in Journal/Newspaper North Atlantic Instituto Universitário de Ciências Psicológicas, Sociais e da Vida: Repositório do ISPA |
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Open Polar |
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Instituto Universitário de Ciências Psicológicas, Sociais e da Vida: Repositório do ISPA |
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ftispalisboa |
language |
English |
description |
The threat of population declines caused by pelagic longline fisheries in the Atlantic has increased the concern to find strategies that minimize the bycatch and mortality of non-target marine animals. Gear modification, such as the use of circle hooks instead of conventional J-hooks, has been identified as an effective bycatch reduction strategy in different pelagic longline fisheries around the world. This study aimed to verify the effectiveness of the use of circle hooks by quantifying catch rates, relative size selectivity, and anatomical hooking position for the most common target species (swordfish, Xiphias gladius, and blue shark, Prionace glauca), and some bycatch species (loggerhead sea turtles, Caretta caretta, and shortfin mako, Isurus oxyrinchus) caught by the Azorean longline fishing fleet. The trial was conducted for five consecutive years (2000–2004) using eight different types of hooks. In general, the blue shark catches using circle hooks were significantly higher compared to J (Mustad 9/0). The circle hooks also showed high probabilities of catching juvenile blue sharks. Conversely, the circle hooks were efficient in reducing the loggerhead sea turtle bycatch and were related to fewer catches of small sea turtle individuals. The use of circle hooks was also associated with reduced swordfish catches compared to J (Mustad 9/0), and the effect of hook types on length at capture was only significant for Circle (L. & P. 18/0 —CLP18) and Ringed Tuna (RT). No significant differences were observed comparing hook type to either catch rates or size selectivity for shortfin mako. Additionally, circle hooks were more likely to lodge in the mouth than in deeper anatomical positions, when compared to J (Mustad 9/0), for the four species analysed. The present study demonstrated that the use of circle hooks could mitigate the impact of the pelagic longline fisheries in the Azores by decreasing the bycatch of sea turtles and reducing animal injuries caused by deep hooking. ... |
format |
Article in Journal/Newspaper |
author |
Lima, Françoise Parra, Hugo Alves, Rita B. Santos, Marco A. R. Bjorndal, Karen Bolten, Alan B. Vandeperre, Frederic |
spellingShingle |
Lima, Françoise Parra, Hugo Alves, Rita B. Santos, Marco A. R. Bjorndal, Karen Bolten, Alan B. Vandeperre, Frederic Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study |
author_facet |
Lima, Françoise Parra, Hugo Alves, Rita B. Santos, Marco A. R. Bjorndal, Karen Bolten, Alan B. Vandeperre, Frederic |
author_sort |
Lima, Françoise |
title |
Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study |
title_short |
Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study |
title_full |
Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study |
title_fullStr |
Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study |
title_full_unstemmed |
Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study |
title_sort |
effects of gear modifications in a north atlantic pelagic longline fishery: a multiyear study |
publisher |
Public Library of Science |
publishDate |
2024 |
url |
http://hdl.handle.net/10400.12/9647 https://doi.org/10.1371/journal.pone.0292727 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
Lima FD, Parra H, Alves RB, Santos MAR, Bjorndal KA, Bolten AB, et al. (2023) Effects of gear modifications in a North Atlantic pelagic longline fishery: A multiyear study. PLoS ONE 18(10): e0292727. https://doi.org/10.1371/journal. pone.0292727 19326203 http://hdl.handle.net/10400.12/9647 doi:10.1371/journal.pone.0292727 |
op_rights |
openAccess http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1371/journal.pone.029272710.1371/journal |
_version_ |
1810464661618819072 |