Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland
Abstract Holmes, S. J., Wright, P. J., and Fryer, R. J. 2008. Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland. – ICES Journal of Marine Science, 65: 206–215. Although cod (Gadus morhua) in the North Sea and ICES Division VIa are assessed as si...
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Online Access: | http://dx.doi.org/10.1093/icesjms/fsm192 http://academic.oup.com/icesjms/article-pdf/65/2/206/29129642/fsm192.pdf |
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croxfordunivpr:10.1093/icesjms/fsm192 2023-12-31T10:07:03+01:00 Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland Holmes, Steven J. Wright, Peter J. Fryer, Robert J. 2008 http://dx.doi.org/10.1093/icesjms/fsm192 http://academic.oup.com/icesjms/article-pdf/65/2/206/29129642/fsm192.pdf en eng Oxford University Press (OUP) ICES Journal of Marine Science volume 65, issue 2, page 206-215 ISSN 1095-9289 1054-3139 Ecology Aquatic Science Ecology, Evolution, Behavior and Systematics Oceanography journal-article 2008 croxfordunivpr https://doi.org/10.1093/icesjms/fsm192 2023-12-06T08:55:44Z Abstract Holmes, S. J., Wright, P. J., and Fryer, R. J. 2008. Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland. – ICES Journal of Marine Science, 65: 206–215. Although cod (Gadus morhua) in the North Sea and ICES Division VIa are assessed as single units, recent research suggests that the stocks consist of reproductively isolated subpopulations within a metapopulation. We investigate whether temporal trends in stock indicators are asynchronous across subpopulations, which would support the metapopulation hypothesis. First quarter trawl survey data for the years 1983–2005 were aggregated into putative areas of high spawner fidelity (three in VIa, seven in the North Sea) to obtain indices of spawning–stock biomass (SSB) and recruitment (numbers-at-age 1). Asynchrony was investigated by fitting a smoother to the data for each of the ten spawning areas and testing whether the smoothers were parallel. Trends in SSB differed between spawning areas in both VIa and the North Sea. In VIa, SSB collapsed in the most southwesterly area, but remained more constant elsewhere. In the North Sea, there was a general decline in SSB, but areas thought to contain resident inshore populations showed more rapid declines than those in adjacent offshore areas. Recruitment results offered less support for a metapopulation, although recruitment in the southern North Sea declined rapidly before any trend was seen for the North Sea as a whole. Article in Journal/Newspaper Gadus morhua Oxford University Press (via Crossref) ICES Journal of Marine Science 65 2 206 215 |
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Open Polar |
collection |
Oxford University Press (via Crossref) |
op_collection_id |
croxfordunivpr |
language |
English |
topic |
Ecology Aquatic Science Ecology, Evolution, Behavior and Systematics Oceanography |
spellingShingle |
Ecology Aquatic Science Ecology, Evolution, Behavior and Systematics Oceanography Holmes, Steven J. Wright, Peter J. Fryer, Robert J. Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland |
topic_facet |
Ecology Aquatic Science Ecology, Evolution, Behavior and Systematics Oceanography |
description |
Abstract Holmes, S. J., Wright, P. J., and Fryer, R. J. 2008. Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland. – ICES Journal of Marine Science, 65: 206–215. Although cod (Gadus morhua) in the North Sea and ICES Division VIa are assessed as single units, recent research suggests that the stocks consist of reproductively isolated subpopulations within a metapopulation. We investigate whether temporal trends in stock indicators are asynchronous across subpopulations, which would support the metapopulation hypothesis. First quarter trawl survey data for the years 1983–2005 were aggregated into putative areas of high spawner fidelity (three in VIa, seven in the North Sea) to obtain indices of spawning–stock biomass (SSB) and recruitment (numbers-at-age 1). Asynchrony was investigated by fitting a smoother to the data for each of the ten spawning areas and testing whether the smoothers were parallel. Trends in SSB differed between spawning areas in both VIa and the North Sea. In VIa, SSB collapsed in the most southwesterly area, but remained more constant elsewhere. In the North Sea, there was a general decline in SSB, but areas thought to contain resident inshore populations showed more rapid declines than those in adjacent offshore areas. Recruitment results offered less support for a metapopulation, although recruitment in the southern North Sea declined rapidly before any trend was seen for the North Sea as a whole. |
format |
Article in Journal/Newspaper |
author |
Holmes, Steven J. Wright, Peter J. Fryer, Robert J. |
author_facet |
Holmes, Steven J. Wright, Peter J. Fryer, Robert J. |
author_sort |
Holmes, Steven J. |
title |
Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland |
title_short |
Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland |
title_full |
Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland |
title_fullStr |
Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland |
title_full_unstemmed |
Evidence from survey data for regional variability in cod dynamics in the North Sea and West of Scotland |
title_sort |
evidence from survey data for regional variability in cod dynamics in the north sea and west of scotland |
publisher |
Oxford University Press (OUP) |
publishDate |
2008 |
url |
http://dx.doi.org/10.1093/icesjms/fsm192 http://academic.oup.com/icesjms/article-pdf/65/2/206/29129642/fsm192.pdf |
genre |
Gadus morhua |
genre_facet |
Gadus morhua |
op_source |
ICES Journal of Marine Science volume 65, issue 2, page 206-215 ISSN 1095-9289 1054-3139 |
op_doi |
https://doi.org/10.1093/icesjms/fsm192 |
container_title |
ICES Journal of Marine Science |
container_volume |
65 |
container_issue |
2 |
container_start_page |
206 |
op_container_end_page |
215 |
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1786839286047309824 |