Role of Stock Biomass and Temperature in Recruitment of Southern Gulf of St. Lawrence Atlantic Cod, Gadus morhua
A multivariate approach was used to elucidate the simultaneous effects of temperature and estimated parent stock biomass on the recruitment mechanism of Gulf of St. Lawrence cod. The second order effects of temperature and estimated stock biomass were key factors in determining egg abundance levels....
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Canadian Science Publishing
1975
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Online Access: | http://dx.doi.org/10.1139/f75-187 http://www.nrcresearchpress.com/doi/pdf/10.1139/f75-187 |
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crcansciencepubl:10.1139/f75-187 2023-12-17T10:27:04+01:00 Role of Stock Biomass and Temperature in Recruitment of Southern Gulf of St. Lawrence Atlantic Cod, Gadus morhua Lett, P. F. Kohler, A. C. Fitzgerald, D. N. 1975 http://dx.doi.org/10.1139/f75-187 http://www.nrcresearchpress.com/doi/pdf/10.1139/f75-187 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Journal of the Fisheries Research Board of Canada volume 32, issue 9, page 1613-1627 ISSN 0015-296X General Medicine journal-article 1975 crcansciencepubl https://doi.org/10.1139/f75-187 2023-11-19T13:39:29Z A multivariate approach was used to elucidate the simultaneous effects of temperature and estimated parent stock biomass on the recruitment mechanism of Gulf of St. Lawrence cod. The second order effects of temperature and estimated stock biomass were key factors in determining egg abundance levels. In addition, egg abundance was closely related to the growth rate of cod. The numbers of larvae increased with the interaction of temperature with egg abundance but decreased with the interaction of egg abundance and time. The most important step in the recruitment mechanism occurs during the juvenile stage, the degree of density dependence being reliant on total biomass of the adult cod stock. A system simulation was constructed amalgamating the equations of early life history of cod with the effects of exploitation on stock biomass. Regular 12-yr oscillations were demonstrated at low levels of catch, while the population became more stable at higher fishing efforts in the absence of environmental effects. The optimal fishing mortality for the Gulf of St. Lawrence cod was found to be F 0.4 , with a maximum sustainable yield of 42,000 metric tons. Article in Journal/Newspaper atlantic cod Gadus morhua Canadian Science Publishing (via Crossref) Journal of the Fisheries Research Board of Canada 32 9 1613 1627 |
institution |
Open Polar |
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Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
General Medicine |
spellingShingle |
General Medicine Lett, P. F. Kohler, A. C. Fitzgerald, D. N. Role of Stock Biomass and Temperature in Recruitment of Southern Gulf of St. Lawrence Atlantic Cod, Gadus morhua |
topic_facet |
General Medicine |
description |
A multivariate approach was used to elucidate the simultaneous effects of temperature and estimated parent stock biomass on the recruitment mechanism of Gulf of St. Lawrence cod. The second order effects of temperature and estimated stock biomass were key factors in determining egg abundance levels. In addition, egg abundance was closely related to the growth rate of cod. The numbers of larvae increased with the interaction of temperature with egg abundance but decreased with the interaction of egg abundance and time. The most important step in the recruitment mechanism occurs during the juvenile stage, the degree of density dependence being reliant on total biomass of the adult cod stock. A system simulation was constructed amalgamating the equations of early life history of cod with the effects of exploitation on stock biomass. Regular 12-yr oscillations were demonstrated at low levels of catch, while the population became more stable at higher fishing efforts in the absence of environmental effects. The optimal fishing mortality for the Gulf of St. Lawrence cod was found to be F 0.4 , with a maximum sustainable yield of 42,000 metric tons. |
format |
Article in Journal/Newspaper |
author |
Lett, P. F. Kohler, A. C. Fitzgerald, D. N. |
author_facet |
Lett, P. F. Kohler, A. C. Fitzgerald, D. N. |
author_sort |
Lett, P. F. |
title |
Role of Stock Biomass and Temperature in Recruitment of Southern Gulf of St. Lawrence Atlantic Cod, Gadus morhua |
title_short |
Role of Stock Biomass and Temperature in Recruitment of Southern Gulf of St. Lawrence Atlantic Cod, Gadus morhua |
title_full |
Role of Stock Biomass and Temperature in Recruitment of Southern Gulf of St. Lawrence Atlantic Cod, Gadus morhua |
title_fullStr |
Role of Stock Biomass and Temperature in Recruitment of Southern Gulf of St. Lawrence Atlantic Cod, Gadus morhua |
title_full_unstemmed |
Role of Stock Biomass and Temperature in Recruitment of Southern Gulf of St. Lawrence Atlantic Cod, Gadus morhua |
title_sort |
role of stock biomass and temperature in recruitment of southern gulf of st. lawrence atlantic cod, gadus morhua |
publisher |
Canadian Science Publishing |
publishDate |
1975 |
url |
http://dx.doi.org/10.1139/f75-187 http://www.nrcresearchpress.com/doi/pdf/10.1139/f75-187 |
genre |
atlantic cod Gadus morhua |
genre_facet |
atlantic cod Gadus morhua |
op_source |
Journal of the Fisheries Research Board of Canada volume 32, issue 9, page 1613-1627 ISSN 0015-296X |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f75-187 |
container_title |
Journal of the Fisheries Research Board of Canada |
container_volume |
32 |
container_issue |
9 |
container_start_page |
1613 |
op_container_end_page |
1627 |
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1785578842610466816 |