Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments
Fishery inspector logbooks were used to estimate fishing gear interaction rates for humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries for herring from 2011 to 2020. Estimated rates were applied to fisheries data to estimate fleet-wide totals. Estim...
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Online Access: | https://hdl.handle.net/11250/3033067 https://doi.org/10.1111/mms.12985 |
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ftimr:oai:imr.brage.unit.no:11250/3033067 2023-05-15T17:10:47+02:00 Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments Bjørge, Arne Jostein Moan, André Ryeng, Kathrine Wiig, Jørgen Ree 2022 application/pdf https://hdl.handle.net/11250/3033067 https://doi.org/10.1111/mms.12985 eng eng Marine mammal science. 2022, . urn:issn:0824-0469 https://hdl.handle.net/11250/3033067 https://doi.org/10.1111/mms.12985 cristin:2069531 11 Marine mammal science Peer reviewed Journal article 2022 ftimr https://doi.org/10.1111/mms.12985 2022-11-23T23:43:05Z Fishery inspector logbooks were used to estimate fishing gear interaction rates for humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries for herring from 2011 to 2020. Estimated rates were applied to fisheries data to estimate fleet-wide totals. Estimates showed that in a 10-year period, a total of 78 humpback whales, 95% CI [41, 145] and 100 killer whales, 95% CI [63, 176] were entrapped in purse seines. Most whales were disentangled alive, with an estimated mortality of 5%, CV 0.69, 95% CI [0.0, 11.8] and 6%, CV 0.48, 95% CI [0.3, 11.9], respectively. The average yearly mortality over the study period was thus approximately 0.60 killer whales and 0.39 humpback whales corresponding to 0.008% and 0.007% of the respective abundance estimates for these whale species in Norwegian waters. Given the Potential Biological Removal sustainability limits of 98 humpbacks and 161 killer whales per year, it may be concluded that, by itself, the average yearly mortality incurred by these whale populations by Norwegian fisheries does not constitute a significant risk to either of these species, but bycatch in Norwegian purse seine fisheries may not be the only source of anthropogenic mortality. Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments publishedVersion Article in Journal/Newspaper Megaptera novaeangliae Orca Orcinus orca Institute for Marine Research: Brage IMR Marine Mammal Science |
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Open Polar |
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Institute for Marine Research: Brage IMR |
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ftimr |
language |
English |
description |
Fishery inspector logbooks were used to estimate fishing gear interaction rates for humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries for herring from 2011 to 2020. Estimated rates were applied to fisheries data to estimate fleet-wide totals. Estimates showed that in a 10-year period, a total of 78 humpback whales, 95% CI [41, 145] and 100 killer whales, 95% CI [63, 176] were entrapped in purse seines. Most whales were disentangled alive, with an estimated mortality of 5%, CV 0.69, 95% CI [0.0, 11.8] and 6%, CV 0.48, 95% CI [0.3, 11.9], respectively. The average yearly mortality over the study period was thus approximately 0.60 killer whales and 0.39 humpback whales corresponding to 0.008% and 0.007% of the respective abundance estimates for these whale species in Norwegian waters. Given the Potential Biological Removal sustainability limits of 98 humpbacks and 161 killer whales per year, it may be concluded that, by itself, the average yearly mortality incurred by these whale populations by Norwegian fisheries does not constitute a significant risk to either of these species, but bycatch in Norwegian purse seine fisheries may not be the only source of anthropogenic mortality. Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments publishedVersion |
format |
Article in Journal/Newspaper |
author |
Bjørge, Arne Jostein Moan, André Ryeng, Kathrine Wiig, Jørgen Ree |
spellingShingle |
Bjørge, Arne Jostein Moan, André Ryeng, Kathrine Wiig, Jørgen Ree Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments |
author_facet |
Bjørge, Arne Jostein Moan, André Ryeng, Kathrine Wiig, Jørgen Ree |
author_sort |
Bjørge, Arne Jostein |
title |
Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments |
title_short |
Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments |
title_full |
Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments |
title_fullStr |
Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments |
title_full_unstemmed |
Low anthropogenic mortality of humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries despite frequent entrapments |
title_sort |
low anthropogenic mortality of humpback (megaptera novaeangliae) and killer (orcinus orca) whales in norwegian purse seine fisheries despite frequent entrapments |
publishDate |
2022 |
url |
https://hdl.handle.net/11250/3033067 https://doi.org/10.1111/mms.12985 |
genre |
Megaptera novaeangliae Orca Orcinus orca |
genre_facet |
Megaptera novaeangliae Orca Orcinus orca |
op_source |
11 Marine mammal science |
op_relation |
Marine mammal science. 2022, . urn:issn:0824-0469 https://hdl.handle.net/11250/3033067 https://doi.org/10.1111/mms.12985 cristin:2069531 |
op_doi |
https://doi.org/10.1111/mms.12985 |
container_title |
Marine Mammal Science |
_version_ |
1766067437258670080 |