Growth, condition, and environmental relationships in Atlantic cod ( Gadus morhua) in the northern Gulf of St. Lawrence and implications for management strategies in the Northwest Atlantic
Northern Gulf of St. Lawrence Atlantic cod (Gadus morhua) is one of several stocks that collapsed in eastern Canada following a long period of intensive exploitation. Surplus and net production per capita became nil or negative in the mid-1980s so that any level of exploitation would have caused a d...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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1999
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Online Access: | http://dx.doi.org/10.1139/f99-140 http://www.nrcresearchpress.com/doi/pdf/10.1139/f99-140 |
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crcansciencepubl:10.1139/f99-140 2024-09-15T17:55:27+00:00 Growth, condition, and environmental relationships in Atlantic cod ( Gadus morhua) in the northern Gulf of St. Lawrence and implications for management strategies in the Northwest Atlantic Dutil, J -D Castonguay, M Gilbert, D Gascon, D 1999 http://dx.doi.org/10.1139/f99-140 http://www.nrcresearchpress.com/doi/pdf/10.1139/f99-140 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 56, issue 10, page 1818-1831 ISSN 0706-652X 1205-7533 journal-article 1999 crcansciencepubl https://doi.org/10.1139/f99-140 2024-08-22T04:08:44Z Northern Gulf of St. Lawrence Atlantic cod (Gadus morhua) is one of several stocks that collapsed in eastern Canada following a long period of intensive exploitation. Surplus and net production per capita became nil or negative in the mid-1980s so that any level of exploitation would have caused a decline of the stock. This was partly explained by a marked decline in growth production and is consistent with smaller sizes-at-age but also lower condition factor values during the same period. Correlations between size-at-age and temperature were not significant when corrected for autocorrelation, but slopes were always positive, suggesting higher growth rates at higher temperatures. Smaller sizes-at-age in the 1980s were not associated with changes in the fishery or increased fishing mortality, nor were they consistent with the density-dependence hypothesis. Lengths at age 8 decreased by more than 10 cm as the stock decreased 10-fold in abundance. While size-at-age and temperature covary in cod when all stocks are examined, size-temperature relationships are not as clear if the analysis is restricted to cold-water stocks, possibly because of differences in food availability. Biological production varies from year to year and among stocks and should be taken into consideration when managing fisheries in variable or extreme environments. Article in Journal/Newspaper atlantic cod Gadus morhua Northwest Atlantic Canadian Science Publishing Canadian Journal of Fisheries and Aquatic Sciences 56 10 1818 1831 |
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Open Polar |
collection |
Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
Northern Gulf of St. Lawrence Atlantic cod (Gadus morhua) is one of several stocks that collapsed in eastern Canada following a long period of intensive exploitation. Surplus and net production per capita became nil or negative in the mid-1980s so that any level of exploitation would have caused a decline of the stock. This was partly explained by a marked decline in growth production and is consistent with smaller sizes-at-age but also lower condition factor values during the same period. Correlations between size-at-age and temperature were not significant when corrected for autocorrelation, but slopes were always positive, suggesting higher growth rates at higher temperatures. Smaller sizes-at-age in the 1980s were not associated with changes in the fishery or increased fishing mortality, nor were they consistent with the density-dependence hypothesis. Lengths at age 8 decreased by more than 10 cm as the stock decreased 10-fold in abundance. While size-at-age and temperature covary in cod when all stocks are examined, size-temperature relationships are not as clear if the analysis is restricted to cold-water stocks, possibly because of differences in food availability. Biological production varies from year to year and among stocks and should be taken into consideration when managing fisheries in variable or extreme environments. |
format |
Article in Journal/Newspaper |
author |
Dutil, J -D Castonguay, M Gilbert, D Gascon, D |
spellingShingle |
Dutil, J -D Castonguay, M Gilbert, D Gascon, D Growth, condition, and environmental relationships in Atlantic cod ( Gadus morhua) in the northern Gulf of St. Lawrence and implications for management strategies in the Northwest Atlantic |
author_facet |
Dutil, J -D Castonguay, M Gilbert, D Gascon, D |
author_sort |
Dutil, J -D |
title |
Growth, condition, and environmental relationships in Atlantic cod ( Gadus morhua) in the northern Gulf of St. Lawrence and implications for management strategies in the Northwest Atlantic |
title_short |
Growth, condition, and environmental relationships in Atlantic cod ( Gadus morhua) in the northern Gulf of St. Lawrence and implications for management strategies in the Northwest Atlantic |
title_full |
Growth, condition, and environmental relationships in Atlantic cod ( Gadus morhua) in the northern Gulf of St. Lawrence and implications for management strategies in the Northwest Atlantic |
title_fullStr |
Growth, condition, and environmental relationships in Atlantic cod ( Gadus morhua) in the northern Gulf of St. Lawrence and implications for management strategies in the Northwest Atlantic |
title_full_unstemmed |
Growth, condition, and environmental relationships in Atlantic cod ( Gadus morhua) in the northern Gulf of St. Lawrence and implications for management strategies in the Northwest Atlantic |
title_sort |
growth, condition, and environmental relationships in atlantic cod ( gadus morhua) in the northern gulf of st. lawrence and implications for management strategies in the northwest atlantic |
publisher |
Canadian Science Publishing |
publishDate |
1999 |
url |
http://dx.doi.org/10.1139/f99-140 http://www.nrcresearchpress.com/doi/pdf/10.1139/f99-140 |
genre |
atlantic cod Gadus morhua Northwest Atlantic |
genre_facet |
atlantic cod Gadus morhua Northwest Atlantic |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 56, issue 10, page 1818-1831 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f99-140 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
container_volume |
56 |
container_issue |
10 |
container_start_page |
1818 |
op_container_end_page |
1831 |
_version_ |
1810431733983608832 |