Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines
The Greenland Shark (Somniosus microcephalus) is the most common bycatch in the Greenland halibut (Reinhardtius hippoglossoides) bottom longline fishery in Cumberland Sound, Canada. Historically, this inshore fishery has been prosecuted through the ice during winter but winter storms and unpredictab...
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ftdoajarticles:oai:doaj.org/article:ac3d2323ac1941408318312c2a273e8b 2024-01-07T09:42:52+01:00 Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines Scott M. Grant Rennie Sullivan Kevin J. Hedges 2018-05-01T00:00:00Z https://doi.org/10.7717/peerj.4751 https://doaj.org/article/ac3d2323ac1941408318312c2a273e8b EN eng PeerJ Inc. https://peerj.com/articles/4751.pdf https://peerj.com/articles/4751/ https://doaj.org/toc/2167-8359 doi:10.7717/peerj.4751 2167-8359 https://doaj.org/article/ac3d2323ac1941408318312c2a273e8b PeerJ, Vol 6, p e4751 (2018) Greenland shark Longlines Shark deterrent technology Bycatch mitigation Inertial suction Feeding behavior Medicine R Biology (General) QH301-705.5 article 2018 ftdoajarticles https://doi.org/10.7717/peerj.4751 2023-12-10T01:52:30Z The Greenland Shark (Somniosus microcephalus) is the most common bycatch in the Greenland halibut (Reinhardtius hippoglossoides) bottom longline fishery in Cumberland Sound, Canada. Historically, this inshore fishery has been prosecuted through the ice during winter but winter storms and unpredictable landfast ice conditions since the mid-1990s have led to interest in developing a summer fishery during the ice-free season. However, bycatch of Greenland shark was found to increase substantially with 570 sharks captured during an experimental Greenland halibut summer fishery (i.e., mean of 6.3 sharks per 1,000 hooks set) and mortality was reported to be about 50% due in part to fishers killing sharks that were severely entangled in longline gear. This study investigated whether the SMART (Selective Magnetic and Repellent-Treated) hook technology is a practical deterrent to Greenland shark predation and subsequent bycatch on bottom longlines. Greenland shark feeding behavior, feeding kinematics, and variables affecting entanglement/disentanglement and release are also described. The SMART hook failed to deter Greenland shark predation, i.e., all sharks were captured on SMART hooks, some with more than one SMART hook in their jaw. Moreover, recently captured Greenland sharks did not exhibit a behavioral response to SMART hooks. In situ observations of Greenland shark feeding show that this species uses a powerful inertial suction mode of feeding and was able to draw bait into the mouth from a distance of 25–35 cm. This method of feeding is suggested to negate the potential deterrent effects of electropositive metal and magnetic alloy substitutions to the SMART hook technology. The number of hooks entangled by a Greenland shark and time to disentangle and live-release a shark was found to increase with body length. Article in Journal/Newspaper Cumberland Sound Greenland Somniosus microcephalus Directory of Open Access Journals: DOAJ Articles Canada Greenland Cumberland Sound ENVELOPE(-66.014,-66.014,65.334,65.334) PeerJ 6 e4751 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Greenland shark Longlines Shark deterrent technology Bycatch mitigation Inertial suction Feeding behavior Medicine R Biology (General) QH301-705.5 |
spellingShingle |
Greenland shark Longlines Shark deterrent technology Bycatch mitigation Inertial suction Feeding behavior Medicine R Biology (General) QH301-705.5 Scott M. Grant Rennie Sullivan Kevin J. Hedges Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines |
topic_facet |
Greenland shark Longlines Shark deterrent technology Bycatch mitigation Inertial suction Feeding behavior Medicine R Biology (General) QH301-705.5 |
description |
The Greenland Shark (Somniosus microcephalus) is the most common bycatch in the Greenland halibut (Reinhardtius hippoglossoides) bottom longline fishery in Cumberland Sound, Canada. Historically, this inshore fishery has been prosecuted through the ice during winter but winter storms and unpredictable landfast ice conditions since the mid-1990s have led to interest in developing a summer fishery during the ice-free season. However, bycatch of Greenland shark was found to increase substantially with 570 sharks captured during an experimental Greenland halibut summer fishery (i.e., mean of 6.3 sharks per 1,000 hooks set) and mortality was reported to be about 50% due in part to fishers killing sharks that were severely entangled in longline gear. This study investigated whether the SMART (Selective Magnetic and Repellent-Treated) hook technology is a practical deterrent to Greenland shark predation and subsequent bycatch on bottom longlines. Greenland shark feeding behavior, feeding kinematics, and variables affecting entanglement/disentanglement and release are also described. The SMART hook failed to deter Greenland shark predation, i.e., all sharks were captured on SMART hooks, some with more than one SMART hook in their jaw. Moreover, recently captured Greenland sharks did not exhibit a behavioral response to SMART hooks. In situ observations of Greenland shark feeding show that this species uses a powerful inertial suction mode of feeding and was able to draw bait into the mouth from a distance of 25–35 cm. This method of feeding is suggested to negate the potential deterrent effects of electropositive metal and magnetic alloy substitutions to the SMART hook technology. The number of hooks entangled by a Greenland shark and time to disentangle and live-release a shark was found to increase with body length. |
format |
Article in Journal/Newspaper |
author |
Scott M. Grant Rennie Sullivan Kevin J. Hedges |
author_facet |
Scott M. Grant Rennie Sullivan Kevin J. Hedges |
author_sort |
Scott M. Grant |
title |
Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines |
title_short |
Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines |
title_full |
Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines |
title_fullStr |
Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines |
title_full_unstemmed |
Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines |
title_sort |
greenland shark (somniosus microcephalus) feeding behavior on static fishing gear, effect of smart (selective magnetic and repellent-treated) hook deterrent technology, and factors influencing entanglement in bottom longlines |
publisher |
PeerJ Inc. |
publishDate |
2018 |
url |
https://doi.org/10.7717/peerj.4751 https://doaj.org/article/ac3d2323ac1941408318312c2a273e8b |
long_lat |
ENVELOPE(-66.014,-66.014,65.334,65.334) |
geographic |
Canada Greenland Cumberland Sound |
geographic_facet |
Canada Greenland Cumberland Sound |
genre |
Cumberland Sound Greenland Somniosus microcephalus |
genre_facet |
Cumberland Sound Greenland Somniosus microcephalus |
op_source |
PeerJ, Vol 6, p e4751 (2018) |
op_relation |
https://peerj.com/articles/4751.pdf https://peerj.com/articles/4751/ https://doaj.org/toc/2167-8359 doi:10.7717/peerj.4751 2167-8359 https://doaj.org/article/ac3d2323ac1941408318312c2a273e8b |
op_doi |
https://doi.org/10.7717/peerj.4751 |
container_title |
PeerJ |
container_volume |
6 |
container_start_page |
e4751 |
_version_ |
1787424125028925440 |