Atlantic salmon return rate increases with smolt length
Abstract Recent declines in Atlantic salmon Salmo salar populations are generally attributed to factors in their marine life-phase. However, it is postulated that factors affecting their freshwater life-phase might impact their marine survival, such as the influence of body size. While larger smolts...
Published in: | ICES Journal of Marine Science |
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Oxford University Press (OUP)
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Online Access: | http://dx.doi.org/10.1093/icesjms/fsz066 http://academic.oup.com/icesjms/article-pdf/76/6/1702/31247370/fsz066.pdf |
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croxfordunivpr:10.1093/icesjms/fsz066 2024-10-06T13:47:20+00:00 Atlantic salmon return rate increases with smolt length Gregory, Stephen D Ibbotson, Anton T Riley, William D Nevoux, Marie Lauridsen, Rasmus B Russell, Ian C Britton, J Robert Gillingham, Phillipa K Simmons, Olivia M Rivot, Etienne Durif, Caroline European Regional Development Fund Interreg Channel VA Programme U.K. Government’s Department for Environment, Food and Rural Affairs 2019 http://dx.doi.org/10.1093/icesjms/fsz066 http://academic.oup.com/icesjms/article-pdf/76/6/1702/31247370/fsz066.pdf en eng Oxford University Press (OUP) https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model ICES Journal of Marine Science volume 76, issue 6, page 1702-1712 ISSN 1054-3139 1095-9289 journal-article 2019 croxfordunivpr https://doi.org/10.1093/icesjms/fsz066 2024-09-10T04:15:01Z Abstract Recent declines in Atlantic salmon Salmo salar populations are generally attributed to factors in their marine life-phase. However, it is postulated that factors affecting their freshwater life-phase might impact their marine survival, such as the influence of body size. While larger smolts are widely hypothesized to have higher marine survival rates, empirical support remains scant, in part due to inadequate data and ambiguous statistical analyses. Here, we test the influence of smolt body size on marine return rates, a proxy for marine survival, using a 12-year dataset of 3688 smolts tagged with passive integrated transponders in the River Frome, Southern England. State-space models describe the probability of smolts surviving their marine phase to return as 1 sea-winter (1SW) or multi-sea-winter adults as a function of their length, while accounting for imperfect detection and missing data. Models predicted that larger smolts had higher return rates; the most parsimonious model included the effect of length on 1SW return rate. This prediction is concerning, as freshwater juvenile salmon are decreasing in size on the River Frome, and elsewhere. Thus, to maximize adult returns, restoration efforts should focus on freshwater life-stages, and maximize both the number and the size of emigrating smolts. Article in Journal/Newspaper Atlantic salmon Salmo salar Oxford University Press ICES Journal of Marine Science 76 6 1702 1712 |
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Open Polar |
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Oxford University Press |
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croxfordunivpr |
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English |
description |
Abstract Recent declines in Atlantic salmon Salmo salar populations are generally attributed to factors in their marine life-phase. However, it is postulated that factors affecting their freshwater life-phase might impact their marine survival, such as the influence of body size. While larger smolts are widely hypothesized to have higher marine survival rates, empirical support remains scant, in part due to inadequate data and ambiguous statistical analyses. Here, we test the influence of smolt body size on marine return rates, a proxy for marine survival, using a 12-year dataset of 3688 smolts tagged with passive integrated transponders in the River Frome, Southern England. State-space models describe the probability of smolts surviving their marine phase to return as 1 sea-winter (1SW) or multi-sea-winter adults as a function of their length, while accounting for imperfect detection and missing data. Models predicted that larger smolts had higher return rates; the most parsimonious model included the effect of length on 1SW return rate. This prediction is concerning, as freshwater juvenile salmon are decreasing in size on the River Frome, and elsewhere. Thus, to maximize adult returns, restoration efforts should focus on freshwater life-stages, and maximize both the number and the size of emigrating smolts. |
author2 |
Durif, Caroline European Regional Development Fund Interreg Channel VA Programme U.K. Government’s Department for Environment, Food and Rural Affairs |
format |
Article in Journal/Newspaper |
author |
Gregory, Stephen D Ibbotson, Anton T Riley, William D Nevoux, Marie Lauridsen, Rasmus B Russell, Ian C Britton, J Robert Gillingham, Phillipa K Simmons, Olivia M Rivot, Etienne |
spellingShingle |
Gregory, Stephen D Ibbotson, Anton T Riley, William D Nevoux, Marie Lauridsen, Rasmus B Russell, Ian C Britton, J Robert Gillingham, Phillipa K Simmons, Olivia M Rivot, Etienne Atlantic salmon return rate increases with smolt length |
author_facet |
Gregory, Stephen D Ibbotson, Anton T Riley, William D Nevoux, Marie Lauridsen, Rasmus B Russell, Ian C Britton, J Robert Gillingham, Phillipa K Simmons, Olivia M Rivot, Etienne |
author_sort |
Gregory, Stephen D |
title |
Atlantic salmon return rate increases with smolt length |
title_short |
Atlantic salmon return rate increases with smolt length |
title_full |
Atlantic salmon return rate increases with smolt length |
title_fullStr |
Atlantic salmon return rate increases with smolt length |
title_full_unstemmed |
Atlantic salmon return rate increases with smolt length |
title_sort |
atlantic salmon return rate increases with smolt length |
publisher |
Oxford University Press (OUP) |
publishDate |
2019 |
url |
http://dx.doi.org/10.1093/icesjms/fsz066 http://academic.oup.com/icesjms/article-pdf/76/6/1702/31247370/fsz066.pdf |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_source |
ICES Journal of Marine Science volume 76, issue 6, page 1702-1712 ISSN 1054-3139 1095-9289 |
op_rights |
https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model |
op_doi |
https://doi.org/10.1093/icesjms/fsz066 |
container_title |
ICES Journal of Marine Science |
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76 |
container_issue |
6 |
container_start_page |
1702 |
op_container_end_page |
1712 |
_version_ |
1812175558475251712 |