Dive to survive: effects of capture depth on barotraumaand post-release survival of Atlantic cod (Gadus morhua)in recreational fisheries
- Atlantic cod (Gadus morhua) caught in recreational fisheries are commonly released, often with barotrauma after rapid decompression. Mouth-hooked, non-bleeding cod kept in a floating net pen showed mortalities ≥40% when angled from >50 m depth, likely because of cumulative stress from ongoing b...
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Oxford Journals
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Online Access: | http://hdl.handle.net/11250/284926 https://doi.org/10.1093/icesjms/fsv102 |
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ftimr:oai:imr.brage.unit.no:11250/284926 2023-05-15T15:27:24+02:00 Dive to survive: effects of capture depth on barotraumaand post-release survival of Atlantic cod (Gadus morhua)in recreational fisheries Ferter, Keno Weltersbach, Marc Simon Humborstad, Odd Børre Fjelldal, Per Gunnar Sambraus, Florian Strehlow, Harry Vincent Vølstad, Jon Helge 2015-06-09T21:00:05Z application/pdf http://hdl.handle.net/11250/284926 https://doi.org/10.1093/icesjms/fsv102 eng eng Oxford Journals Ferter, K., Weltersbach, M. S., Humborstad, O.-B., Fjelldal, P. G., Sambraus, F., Strehlow, H. V., & Vølstad, J. H. (2015). Dive to survive: effects of capture depth on barotrauma and post-release survival of Atlantic cod (Gadus morhua) in recreational fisheries. ICES Journal of Marine Science: Journal du Conseil. doi:10.1093/icesjms/fsv102 urn:issn:1095-9289 http://hdl.handle.net/11250/284926 https://doi.org/doi:10.1093/icesjms/fsv102 cristin:1247234 Navngivelse-IngenBearbeidelse 3.0 Norge http://creativecommons.org/licenses/by-nd/3.0/no/ CC-BY-ND 15 p. ICES Journal of Marine Science Journal article Peer reviewed 2015 ftimr https://doi.org/10.1093/icesjms/fsv102 2021-09-23T20:14:37Z - Atlantic cod (Gadus morhua) caught in recreational fisheries are commonly released, often with barotrauma after rapid decompression. Mouth-hooked, non-bleeding cod kept in a floating net pen showed mortalities ≥40% when angled from >50 m depth, likely because of cumulative stress from ongoing barotrauma and exposure to warm surface water. In a natural setting, however, cod have the opportunity to descend after release and are not restricted to the surface. In a follow-up study, 97.8% of similarly selected cod managed to dive following immediate release, whereas 2.2% were floaters. No mortality was observed for divers kept in cages, which were lowered to capture depth for 72 h. While the floaters would likely have died in a natural setting, no mortality was observed when they were recompressed and kept at capture depth for 72 h. The occurrence of swim bladder ruptures, swollen coelomic cavities, venous gas embolisms, and gas release around the anus was significantly influenced by capture depth (range 0–90 m). A supplementary radiology study showed inflated swim bladders in 87% of the cod after 72 h, and most barotrauma signs had disappeared after 1 month. This study encourages investigation of survival potential for physoclistous species when high mortalities are assumed but undocumented. Matching natural post-release and containment environment is essential in the experimental setup, as failure to do so may bias survival estimates, particularly when a thermocline is present. Assuming minimal predation, short-term mortality of cod experiencing barotrauma is negligible if cod submerge quickly by themselves and are otherwise not substantially injured. Survival of floaters may be increased by forced recompression to capture depth. Sublethal and long-term impacts of barotrauma remain to be studied. To ensure that cod have sufficient energy to submerge, anglers are encouraged to avoid fighting the fish to exhaustion and to minimize handling before release. Article in Journal/Newspaper atlantic cod Gadus morhua Institute for Marine Research: Brage IMR ICES Journal of Marine Science 72 8 2467 2481 |
institution |
Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
description |
- Atlantic cod (Gadus morhua) caught in recreational fisheries are commonly released, often with barotrauma after rapid decompression. Mouth-hooked, non-bleeding cod kept in a floating net pen showed mortalities ≥40% when angled from >50 m depth, likely because of cumulative stress from ongoing barotrauma and exposure to warm surface water. In a natural setting, however, cod have the opportunity to descend after release and are not restricted to the surface. In a follow-up study, 97.8% of similarly selected cod managed to dive following immediate release, whereas 2.2% were floaters. No mortality was observed for divers kept in cages, which were lowered to capture depth for 72 h. While the floaters would likely have died in a natural setting, no mortality was observed when they were recompressed and kept at capture depth for 72 h. The occurrence of swim bladder ruptures, swollen coelomic cavities, venous gas embolisms, and gas release around the anus was significantly influenced by capture depth (range 0–90 m). A supplementary radiology study showed inflated swim bladders in 87% of the cod after 72 h, and most barotrauma signs had disappeared after 1 month. This study encourages investigation of survival potential for physoclistous species when high mortalities are assumed but undocumented. Matching natural post-release and containment environment is essential in the experimental setup, as failure to do so may bias survival estimates, particularly when a thermocline is present. Assuming minimal predation, short-term mortality of cod experiencing barotrauma is negligible if cod submerge quickly by themselves and are otherwise not substantially injured. Survival of floaters may be increased by forced recompression to capture depth. Sublethal and long-term impacts of barotrauma remain to be studied. To ensure that cod have sufficient energy to submerge, anglers are encouraged to avoid fighting the fish to exhaustion and to minimize handling before release. |
format |
Article in Journal/Newspaper |
author |
Ferter, Keno Weltersbach, Marc Simon Humborstad, Odd Børre Fjelldal, Per Gunnar Sambraus, Florian Strehlow, Harry Vincent Vølstad, Jon Helge |
spellingShingle |
Ferter, Keno Weltersbach, Marc Simon Humborstad, Odd Børre Fjelldal, Per Gunnar Sambraus, Florian Strehlow, Harry Vincent Vølstad, Jon Helge Dive to survive: effects of capture depth on barotraumaand post-release survival of Atlantic cod (Gadus morhua)in recreational fisheries |
author_facet |
Ferter, Keno Weltersbach, Marc Simon Humborstad, Odd Børre Fjelldal, Per Gunnar Sambraus, Florian Strehlow, Harry Vincent Vølstad, Jon Helge |
author_sort |
Ferter, Keno |
title |
Dive to survive: effects of capture depth on barotraumaand post-release survival of Atlantic cod (Gadus morhua)in recreational fisheries |
title_short |
Dive to survive: effects of capture depth on barotraumaand post-release survival of Atlantic cod (Gadus morhua)in recreational fisheries |
title_full |
Dive to survive: effects of capture depth on barotraumaand post-release survival of Atlantic cod (Gadus morhua)in recreational fisheries |
title_fullStr |
Dive to survive: effects of capture depth on barotraumaand post-release survival of Atlantic cod (Gadus morhua)in recreational fisheries |
title_full_unstemmed |
Dive to survive: effects of capture depth on barotraumaand post-release survival of Atlantic cod (Gadus morhua)in recreational fisheries |
title_sort |
dive to survive: effects of capture depth on barotraumaand post-release survival of atlantic cod (gadus morhua)in recreational fisheries |
publisher |
Oxford Journals |
publishDate |
2015 |
url |
http://hdl.handle.net/11250/284926 https://doi.org/10.1093/icesjms/fsv102 |
genre |
atlantic cod Gadus morhua |
genre_facet |
atlantic cod Gadus morhua |
op_source |
15 p. ICES Journal of Marine Science |
op_relation |
Ferter, K., Weltersbach, M. S., Humborstad, O.-B., Fjelldal, P. G., Sambraus, F., Strehlow, H. V., & Vølstad, J. H. (2015). Dive to survive: effects of capture depth on barotrauma and post-release survival of Atlantic cod (Gadus morhua) in recreational fisheries. ICES Journal of Marine Science: Journal du Conseil. doi:10.1093/icesjms/fsv102 urn:issn:1095-9289 http://hdl.handle.net/11250/284926 https://doi.org/doi:10.1093/icesjms/fsv102 cristin:1247234 |
op_rights |
Navngivelse-IngenBearbeidelse 3.0 Norge http://creativecommons.org/licenses/by-nd/3.0/no/ |
op_rightsnorm |
CC-BY-ND |
op_doi |
https://doi.org/10.1093/icesjms/fsv102 |
container_title |
ICES Journal of Marine Science |
container_volume |
72 |
container_issue |
8 |
container_start_page |
2467 |
op_container_end_page |
2481 |
_version_ |
1766357843889356800 |