Whale depredation in the South Georgia Patagonian toothfish (Dissostichus eleginoides) fishery in the South Atlantic: a comparison of estimation methods
Removal of fish from gear by marine predators, known as depredation, is a fishery dependent mortality that needs to be included in stock assessments for affected stocks to avoid misestimation of the assessed resource. Toothed whales engage regularly in depredation from longlines, and while in some r...
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2021
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Online Access: | https://archimer.ifremer.fr/doc/00749/86144/91377.pdf https://doi.org/10.1093/icesjms/fsab212 https://archimer.ifremer.fr/doc/00749/86144/ |
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ftarchimer:oai:archimer.ifremer.fr:86144 2023-05-15T17:54:43+02:00 Whale depredation in the South Georgia Patagonian toothfish (Dissostichus eleginoides) fishery in the South Atlantic: a comparison of estimation methods Earl, Timothy Macleod, Eleanor Soffker, Marta Gasco, Nico Massiot-granier, Felix Tixier, Paul Darby, Christopher 2021-12 application/pdf https://archimer.ifremer.fr/doc/00749/86144/91377.pdf https://doi.org/10.1093/icesjms/fsab212 https://archimer.ifremer.fr/doc/00749/86144/ eng eng Oxford Univ Press https://archimer.ifremer.fr/doc/00749/86144/91377.pdf doi:10.1093/icesjms/fsab212 https://archimer.ifremer.fr/doc/00749/86144/ info:eu-repo/semantics/openAccess restricted use Ices Journal Of Marine Science (1054-3139) (Oxford Univ Press), 2021-12 , Vol. 78 , N. 10 , P. 3817-3833 depredation longline marine mammal modelling odontocete South Atlantic South Georgia text Publication info:eu-repo/semantics/article 2021 ftarchimer https://doi.org/10.1093/icesjms/fsab212 2022-02-08T23:49:45Z Removal of fish from gear by marine predators, known as depredation, is a fishery dependent mortality that needs to be included in stock assessments for affected stocks to avoid misestimation of the assessed resource. Toothed whales engage regularly in depredation from longlines, and while in some regions they leave clear marks of depredation activity, in the longline fisheries in the Southern Ocean they often leave no trace of removal, making it necessary to estimate depredation through modelling approaches. Several modelling approaches have been developed over the past decade in affected Southern Ocean fisheries, and in this paper, we examine five applications of common CPUE model structures to the same dataset from the longline fishery around South Georgia. We then compare the estimates of depredation with those based on observed bycatch ratios. The different model structures estimated very similar annual depredation removals, with all approaches averaging around 5% of the catch removed throughout the entire fishery. While depredation varies spatially, the different modelling approaches consistently highlighted areas where the impact of depredation was highest. Article in Journal/Newspaper Patagonian Toothfish Southern Ocean toothed whales Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) Southern Ocean ICES Journal of Marine Science 78 10 3817 3833 |
institution |
Open Polar |
collection |
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) |
op_collection_id |
ftarchimer |
language |
English |
topic |
depredation longline marine mammal modelling odontocete South Atlantic South Georgia |
spellingShingle |
depredation longline marine mammal modelling odontocete South Atlantic South Georgia Earl, Timothy Macleod, Eleanor Soffker, Marta Gasco, Nico Massiot-granier, Felix Tixier, Paul Darby, Christopher Whale depredation in the South Georgia Patagonian toothfish (Dissostichus eleginoides) fishery in the South Atlantic: a comparison of estimation methods |
topic_facet |
depredation longline marine mammal modelling odontocete South Atlantic South Georgia |
description |
Removal of fish from gear by marine predators, known as depredation, is a fishery dependent mortality that needs to be included in stock assessments for affected stocks to avoid misestimation of the assessed resource. Toothed whales engage regularly in depredation from longlines, and while in some regions they leave clear marks of depredation activity, in the longline fisheries in the Southern Ocean they often leave no trace of removal, making it necessary to estimate depredation through modelling approaches. Several modelling approaches have been developed over the past decade in affected Southern Ocean fisheries, and in this paper, we examine five applications of common CPUE model structures to the same dataset from the longline fishery around South Georgia. We then compare the estimates of depredation with those based on observed bycatch ratios. The different model structures estimated very similar annual depredation removals, with all approaches averaging around 5% of the catch removed throughout the entire fishery. While depredation varies spatially, the different modelling approaches consistently highlighted areas where the impact of depredation was highest. |
format |
Article in Journal/Newspaper |
author |
Earl, Timothy Macleod, Eleanor Soffker, Marta Gasco, Nico Massiot-granier, Felix Tixier, Paul Darby, Christopher |
author_facet |
Earl, Timothy Macleod, Eleanor Soffker, Marta Gasco, Nico Massiot-granier, Felix Tixier, Paul Darby, Christopher |
author_sort |
Earl, Timothy |
title |
Whale depredation in the South Georgia Patagonian toothfish (Dissostichus eleginoides) fishery in the South Atlantic: a comparison of estimation methods |
title_short |
Whale depredation in the South Georgia Patagonian toothfish (Dissostichus eleginoides) fishery in the South Atlantic: a comparison of estimation methods |
title_full |
Whale depredation in the South Georgia Patagonian toothfish (Dissostichus eleginoides) fishery in the South Atlantic: a comparison of estimation methods |
title_fullStr |
Whale depredation in the South Georgia Patagonian toothfish (Dissostichus eleginoides) fishery in the South Atlantic: a comparison of estimation methods |
title_full_unstemmed |
Whale depredation in the South Georgia Patagonian toothfish (Dissostichus eleginoides) fishery in the South Atlantic: a comparison of estimation methods |
title_sort |
whale depredation in the south georgia patagonian toothfish (dissostichus eleginoides) fishery in the south atlantic: a comparison of estimation methods |
publisher |
Oxford Univ Press |
publishDate |
2021 |
url |
https://archimer.ifremer.fr/doc/00749/86144/91377.pdf https://doi.org/10.1093/icesjms/fsab212 https://archimer.ifremer.fr/doc/00749/86144/ |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Patagonian Toothfish Southern Ocean toothed whales |
genre_facet |
Patagonian Toothfish Southern Ocean toothed whales |
op_source |
Ices Journal Of Marine Science (1054-3139) (Oxford Univ Press), 2021-12 , Vol. 78 , N. 10 , P. 3817-3833 |
op_relation |
https://archimer.ifremer.fr/doc/00749/86144/91377.pdf doi:10.1093/icesjms/fsab212 https://archimer.ifremer.fr/doc/00749/86144/ |
op_rights |
info:eu-repo/semantics/openAccess restricted use |
op_doi |
https://doi.org/10.1093/icesjms/fsab212 |
container_title |
ICES Journal of Marine Science |
container_volume |
78 |
container_issue |
10 |
container_start_page |
3817 |
op_container_end_page |
3833 |
_version_ |
1766162530517909504 |