Forage fish and the factors governing recovery of Atlantic cod ( Gadus morhua) on the eastern Scotian Shelf
The stock of Atlantic cod ( Gadus morhua ) on the eastern Scotian Shelf (ESS) collapsed in the early 1990s and showed no sign of recovery during a 15-year fishing moratorium, but has recently increased in abundance. Both the prolonged lack of recovery and the recent improvement have been attributed...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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Canadian Science Publishing
2012
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Online Access: | http://dx.doi.org/10.1139/f2012-045 http://www.nrcresearchpress.com/doi/full-xml/10.1139/f2012-045 http://www.nrcresearchpress.com/doi/pdf/10.1139/f2012-045 |
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crcansciencepubl:10.1139/f2012-045 2024-09-15T17:55:24+00:00 Forage fish and the factors governing recovery of Atlantic cod ( Gadus morhua) on the eastern Scotian Shelf Swain, Douglas P. Mohn, Robert K. Marshall, C. Tara 2012 http://dx.doi.org/10.1139/f2012-045 http://www.nrcresearchpress.com/doi/full-xml/10.1139/f2012-045 http://www.nrcresearchpress.com/doi/pdf/10.1139/f2012-045 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 69, issue 6, page 997-1001 ISSN 0706-652X 1205-7533 journal-article 2012 crcansciencepubl https://doi.org/10.1139/f2012-045 2024-07-11T04:12:01Z The stock of Atlantic cod ( Gadus morhua ) on the eastern Scotian Shelf (ESS) collapsed in the early 1990s and showed no sign of recovery during a 15-year fishing moratorium, but has recently increased in abundance. Both the prolonged lack of recovery and the recent improvement have been attributed to changes in the biomass of forage fishes through effects of predation and competition by these fishes on early life stages of cod. An examination of the relationships between forage fish biomass and the population dynamics of ESS cod provided no support for this hypothesis. Contrary to expectations under this hypothesis, cod recruitment rate was unrelated to forage fish biomass. The main factor delaying recovery was high natural mortality (M) of adult cod. The recent improvement in ESS cod is due to the strong 2004 year class and a decline in M. These factors cannot be attributed to an effect of forage fishes. Both the delay in recovery and recent improvement of the ESS cod stock appear to be due to factors other than interactions with forage fishes. Article in Journal/Newspaper atlantic cod Gadus morhua Canadian Science Publishing Canadian Journal of Fisheries and Aquatic Sciences 69 6 997 1001 |
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Open Polar |
collection |
Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
The stock of Atlantic cod ( Gadus morhua ) on the eastern Scotian Shelf (ESS) collapsed in the early 1990s and showed no sign of recovery during a 15-year fishing moratorium, but has recently increased in abundance. Both the prolonged lack of recovery and the recent improvement have been attributed to changes in the biomass of forage fishes through effects of predation and competition by these fishes on early life stages of cod. An examination of the relationships between forage fish biomass and the population dynamics of ESS cod provided no support for this hypothesis. Contrary to expectations under this hypothesis, cod recruitment rate was unrelated to forage fish biomass. The main factor delaying recovery was high natural mortality (M) of adult cod. The recent improvement in ESS cod is due to the strong 2004 year class and a decline in M. These factors cannot be attributed to an effect of forage fishes. Both the delay in recovery and recent improvement of the ESS cod stock appear to be due to factors other than interactions with forage fishes. |
author2 |
Marshall, C. Tara |
format |
Article in Journal/Newspaper |
author |
Swain, Douglas P. Mohn, Robert K. |
spellingShingle |
Swain, Douglas P. Mohn, Robert K. Forage fish and the factors governing recovery of Atlantic cod ( Gadus morhua) on the eastern Scotian Shelf |
author_facet |
Swain, Douglas P. Mohn, Robert K. |
author_sort |
Swain, Douglas P. |
title |
Forage fish and the factors governing recovery of Atlantic cod ( Gadus morhua) on the eastern Scotian Shelf |
title_short |
Forage fish and the factors governing recovery of Atlantic cod ( Gadus morhua) on the eastern Scotian Shelf |
title_full |
Forage fish and the factors governing recovery of Atlantic cod ( Gadus morhua) on the eastern Scotian Shelf |
title_fullStr |
Forage fish and the factors governing recovery of Atlantic cod ( Gadus morhua) on the eastern Scotian Shelf |
title_full_unstemmed |
Forage fish and the factors governing recovery of Atlantic cod ( Gadus morhua) on the eastern Scotian Shelf |
title_sort |
forage fish and the factors governing recovery of atlantic cod ( gadus morhua) on the eastern scotian shelf |
publisher |
Canadian Science Publishing |
publishDate |
2012 |
url |
http://dx.doi.org/10.1139/f2012-045 http://www.nrcresearchpress.com/doi/full-xml/10.1139/f2012-045 http://www.nrcresearchpress.com/doi/pdf/10.1139/f2012-045 |
genre |
atlantic cod Gadus morhua |
genre_facet |
atlantic cod Gadus morhua |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 69, issue 6, page 997-1001 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f2012-045 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
container_volume |
69 |
container_issue |
6 |
container_start_page |
997 |
op_container_end_page |
1001 |
_version_ |
1810431691549835264 |