Can Atlantic cod ( Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada
The Atlantic cod (Gadus morhua) stock on the eastern Scotian Shelf collapsed in 1993. Over a decade later, in spite of a fisheries moratorium on cod fishing, this stock is at an all-time low. In parallel with the collapse of the cod stock, the abundance of large cod prey, including forage fish, shri...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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Online Access: | http://dx.doi.org/10.1139/f05-086 http://www.nrcresearchpress.com/doi/pdf/10.1139/f05-086 |
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crcansciencepubl:10.1139/f05-086 2024-04-28T08:12:58+00:00 Can Atlantic cod ( Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada Bundy, Alida Fanning, L Paul 2005 http://dx.doi.org/10.1139/f05-086 http://www.nrcresearchpress.com/doi/pdf/10.1139/f05-086 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 62, issue 7, page 1474-1489 ISSN 0706-652X 1205-7533 Aquatic Science Ecology, Evolution, Behavior and Systematics journal-article 2005 crcansciencepubl https://doi.org/10.1139/f05-086 2024-04-09T06:56:31Z The Atlantic cod (Gadus morhua) stock on the eastern Scotian Shelf collapsed in 1993. Over a decade later, in spite of a fisheries moratorium on cod fishing, this stock is at an all-time low. In parallel with the collapse of the cod stock, the abundance of large cod prey, including forage fish, shrimp, and snow crab, has greatly increased. The key question, which we explore using trophic mass-balance models, is what processes are preventing cod from recovering on the eastern Scotian Shelf? Cod were split into large and small cod. Modelling results indicate high predation pressure on small cod. In addition, small cod compete with the abundant forage fish for decreasing prey, and are in below-average condition. Large cod incur high, but unidentified, mortality that we suggest is derived from the poor condition of small cod carried through to adulthood. As a consequence of the removal of cod by fishing and an ensusing trophic cascade, eastern Scotian Shelf cod are trapped in a vicious circle: their abundance is being kept low by predation, causing an abundance so low that cod cannot compete for prey with their exceptionally abundant competitors. Furthermore, these competitors may also prey on younger stages of cod. Article in Journal/Newspaper atlantic cod Gadus morhua Snow crab Canadian Science Publishing Canadian Journal of Fisheries and Aquatic Sciences 62 7 1474 1489 |
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Open Polar |
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Canadian Science Publishing |
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crcansciencepubl |
language |
English |
topic |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
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Aquatic Science Ecology, Evolution, Behavior and Systematics Bundy, Alida Fanning, L Paul Can Atlantic cod ( Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada |
topic_facet |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
description |
The Atlantic cod (Gadus morhua) stock on the eastern Scotian Shelf collapsed in 1993. Over a decade later, in spite of a fisheries moratorium on cod fishing, this stock is at an all-time low. In parallel with the collapse of the cod stock, the abundance of large cod prey, including forage fish, shrimp, and snow crab, has greatly increased. The key question, which we explore using trophic mass-balance models, is what processes are preventing cod from recovering on the eastern Scotian Shelf? Cod were split into large and small cod. Modelling results indicate high predation pressure on small cod. In addition, small cod compete with the abundant forage fish for decreasing prey, and are in below-average condition. Large cod incur high, but unidentified, mortality that we suggest is derived from the poor condition of small cod carried through to adulthood. As a consequence of the removal of cod by fishing and an ensusing trophic cascade, eastern Scotian Shelf cod are trapped in a vicious circle: their abundance is being kept low by predation, causing an abundance so low that cod cannot compete for prey with their exceptionally abundant competitors. Furthermore, these competitors may also prey on younger stages of cod. |
format |
Article in Journal/Newspaper |
author |
Bundy, Alida Fanning, L Paul |
author_facet |
Bundy, Alida Fanning, L Paul |
author_sort |
Bundy, Alida |
title |
Can Atlantic cod ( Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada |
title_short |
Can Atlantic cod ( Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada |
title_full |
Can Atlantic cod ( Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada |
title_fullStr |
Can Atlantic cod ( Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada |
title_full_unstemmed |
Can Atlantic cod ( Gadus morhua) recover? Exploring trophic explanations for the non-recovery of the cod stock on the eastern Scotian Shelf, Canada |
title_sort |
can atlantic cod ( gadus morhua) recover? exploring trophic explanations for the non-recovery of the cod stock on the eastern scotian shelf, canada |
publisher |
Canadian Science Publishing |
publishDate |
2005 |
url |
http://dx.doi.org/10.1139/f05-086 http://www.nrcresearchpress.com/doi/pdf/10.1139/f05-086 |
genre |
atlantic cod Gadus morhua Snow crab |
genre_facet |
atlantic cod Gadus morhua Snow crab |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 62, issue 7, page 1474-1489 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f05-086 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
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62 |
container_issue |
7 |
container_start_page |
1474 |
op_container_end_page |
1489 |
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1797579656834056192 |