Pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales
International audience Depredation is defined as the damage or removal of fish from fishing gear by predators, and is a crucial issue leading to negative impacts on both animals involved in depredation and fisheries. Depredation in longline pelagic fisheries targeting swordfish (Xiphias gladius) and...
Published in: | Journal of Experimental Marine Biology and Ecology |
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Online Access: | https://hal.science/hal-00759951 https://doi.org/10.1016/j.jembe.2012.07.004 |
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ftinraparis:oai:HAL:hal-00759951v1 2024-06-23T07:57:11+00:00 Pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales Rabearisoa, Njaratiana Bach, Pascal Tixier, Paul Guinet, Christophe Institut de Recherche pour le Développement (IRD Réunion ) Centre d'Études Biologiques de Chizé (CEBC) Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS) 2012-07-08 https://hal.science/hal-00759951 https://doi.org/10.1016/j.jembe.2012.07.004 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jembe.2012.07.004 hal-00759951 https://hal.science/hal-00759951 doi:10.1016/j.jembe.2012.07.004 ISSN: 0022-0981 Journal of Experimental Marine Biology and Ecology https://hal.science/hal-00759951 Journal of Experimental Marine Biology and Ecology, 2012, 432-433, pp.55-63. ⟨10.1016/j.jembe.2012.07.004⟩ Fishery interaction Globicephala macrorhynchus Physical protection Pseudorca crassidens Sock design Spider design [SDE]Environmental Sciences info:eu-repo/semantics/article Journal articles 2012 ftinraparis https://doi.org/10.1016/j.jembe.2012.07.004 2024-06-04T14:53:40Z International audience Depredation is defined as the damage or removal of fish from fishing gear by predators, and is a crucial issue leading to negative impacts on both animals involved in depredation and fisheries. Depredation in longline pelagic fisheries targeting swordfish (Xiphias gladius) and tuna (Thunnus spp.) involves short-finned pilot whales (Globicephala macrorhynchus), false killer whales (Pseudorca crassidens) and some pelagic sharks. Since no long-term solution could be found to date, we investigated fishing gear improvement by deploying a technology designed to physically protect the hooked fish by hiding it to predators: the DMD (depredation mitigation device). Two types of DMDs were designed: "spiders" and "socks". The efficiency of "spiders" was tested in November 2007 during a fishing trial of 26 longline fishing operations when 12,480 hooks and 1970 devices were set. The efficiency of "socks" was tested in October 2008 during a fishing trial of 32 longline fishing operations when 13,220 hooks and 339 devices were set. 117 and 24 fish were hooked on branchlines equipped with spiders and socks, respectively and among those devices, 87.3% versus 69.2% were correctly triggered and 80% versus 15% of the fish were correctly protected. A low entanglement rate of the spiders with the fishing gear was found (3.6%), but a higher one was associated to the socks (17.8%). Operational constraints to routinely deploy "spiders" were examined. The number of sets impacted by shark depredation was significantly greater than the number of sets involving toothed whale depredation. However, when depredation occurred, the proportion of fish damaged by toothed whales was significantly greater. While more trials should be carried out to deeply verify the efficiency of DMDs, we remain convinced that considerations of fishing gear technologies might be more actively investigated to propose innovative measures to mitigate toothed whale depredation in pelagic longlining. For this type of gear, innovative technology ... Article in Journal/Newspaper toothed whale toothed whales Institut National de la Recherche Agronomique: ProdINRA Journal of Experimental Marine Biology and Ecology 432-433 55 63 |
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Open Polar |
collection |
Institut National de la Recherche Agronomique: ProdINRA |
op_collection_id |
ftinraparis |
language |
English |
topic |
Fishery interaction Globicephala macrorhynchus Physical protection Pseudorca crassidens Sock design Spider design [SDE]Environmental Sciences |
spellingShingle |
Fishery interaction Globicephala macrorhynchus Physical protection Pseudorca crassidens Sock design Spider design [SDE]Environmental Sciences Rabearisoa, Njaratiana Bach, Pascal Tixier, Paul Guinet, Christophe Pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales |
topic_facet |
Fishery interaction Globicephala macrorhynchus Physical protection Pseudorca crassidens Sock design Spider design [SDE]Environmental Sciences |
description |
International audience Depredation is defined as the damage or removal of fish from fishing gear by predators, and is a crucial issue leading to negative impacts on both animals involved in depredation and fisheries. Depredation in longline pelagic fisheries targeting swordfish (Xiphias gladius) and tuna (Thunnus spp.) involves short-finned pilot whales (Globicephala macrorhynchus), false killer whales (Pseudorca crassidens) and some pelagic sharks. Since no long-term solution could be found to date, we investigated fishing gear improvement by deploying a technology designed to physically protect the hooked fish by hiding it to predators: the DMD (depredation mitigation device). Two types of DMDs were designed: "spiders" and "socks". The efficiency of "spiders" was tested in November 2007 during a fishing trial of 26 longline fishing operations when 12,480 hooks and 1970 devices were set. The efficiency of "socks" was tested in October 2008 during a fishing trial of 32 longline fishing operations when 13,220 hooks and 339 devices were set. 117 and 24 fish were hooked on branchlines equipped with spiders and socks, respectively and among those devices, 87.3% versus 69.2% were correctly triggered and 80% versus 15% of the fish were correctly protected. A low entanglement rate of the spiders with the fishing gear was found (3.6%), but a higher one was associated to the socks (17.8%). Operational constraints to routinely deploy "spiders" were examined. The number of sets impacted by shark depredation was significantly greater than the number of sets involving toothed whale depredation. However, when depredation occurred, the proportion of fish damaged by toothed whales was significantly greater. While more trials should be carried out to deeply verify the efficiency of DMDs, we remain convinced that considerations of fishing gear technologies might be more actively investigated to propose innovative measures to mitigate toothed whale depredation in pelagic longlining. For this type of gear, innovative technology ... |
author2 |
Institut de Recherche pour le Développement (IRD Réunion ) Centre d'Études Biologiques de Chizé (CEBC) Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Rabearisoa, Njaratiana Bach, Pascal Tixier, Paul Guinet, Christophe |
author_facet |
Rabearisoa, Njaratiana Bach, Pascal Tixier, Paul Guinet, Christophe |
author_sort |
Rabearisoa, Njaratiana |
title |
Pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales |
title_short |
Pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales |
title_full |
Pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales |
title_fullStr |
Pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales |
title_full_unstemmed |
Pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales |
title_sort |
pelagic longline fishing trials to shape a mitigation device of the depredation by toothed whales |
publisher |
HAL CCSD |
publishDate |
2012 |
url |
https://hal.science/hal-00759951 https://doi.org/10.1016/j.jembe.2012.07.004 |
genre |
toothed whale toothed whales |
genre_facet |
toothed whale toothed whales |
op_source |
ISSN: 0022-0981 Journal of Experimental Marine Biology and Ecology https://hal.science/hal-00759951 Journal of Experimental Marine Biology and Ecology, 2012, 432-433, pp.55-63. ⟨10.1016/j.jembe.2012.07.004⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jembe.2012.07.004 hal-00759951 https://hal.science/hal-00759951 doi:10.1016/j.jembe.2012.07.004 |
op_doi |
https://doi.org/10.1016/j.jembe.2012.07.004 |
container_title |
Journal of Experimental Marine Biology and Ecology |
container_volume |
432-433 |
container_start_page |
55 |
op_container_end_page |
63 |
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1802650710153625600 |