Time and size at seaward migration influence the sea survival of Salmo salar
Whether time of seaward migration of young Atlantic salmon Salmo salar influences their subsequent survival and growth was investigated in the River Imsa, south-western Norway. Salmo salar were tagged when moving downstream through a trap near the outlet between 1976 and 2010 and recaptured on their...
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Online Access: | http://hdl.handle.net/11250/2478316 https://doi.org/10.1111/jfb.12370 |
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ftninstnf:oai:brage.nina.no:11250/2478316 2023-05-15T15:33:02+02:00 Time and size at seaward migration influence the sea survival of Salmo salar Jonsson, Nina Jonsson, Bror 2014 application/octet-stream http://hdl.handle.net/11250/2478316 https://doi.org/10.1111/jfb.12370 eng eng Andre: Directorate for Nature Management Norges forskningsråd: 225014 Egen institusjon: NINA Journal of Fish Biology. 2014, 84 (5), 1457-1473. urn:issn:0022-1112 http://hdl.handle.net/11250/2478316 https://doi.org/10.1111/jfb.12370 cristin:1133183 1457-1473 84 Journal of Fish Biology 5 Peer reviewed Journal article 2014 ftninstnf https://doi.org/10.1111/jfb.12370 2021-12-23T07:17:10Z Whether time of seaward migration of young Atlantic salmon Salmo salar influences their subsequent survival and growth was investigated in the River Imsa, south-western Norway. Salmo salar were tagged when moving downstream through a trap near the outlet between 1976 and 2010 and recaptured on their adult return.Most descended as smolts in April and May, but some descended during the other months of the year. Annual variation in timing of the smolt migration was significantly correlated with variation in water temperature during spring. Mean total body length of the descending S. salar varied with month of seaward migration. The sea survival of S. salar emigrating from the River Imsa between January and May was 2⋅8 times higher than for those descending between June and December. The sea survival of the various cohorts decreased with increasing river temperature in April to May, prior to the smolt migration, and decreasing day number when the smolts moved to sea. The size of smolts descending the river between April and May did not affect the survival at sea as much as it affected the survival of migrants descending in any other month of the year. The majority of the downstream migrating S. salar were 2 years old, but proportionally, more 1 year olds moved downstream in the autumn than in the rest of the year.Mean duration between downstream migration of the young and the return migration of the grilse was shortest (12⋅7 months) for those descending in July and August and longest for those descending in October (21 months). Mean monthly specific growth rate was highest for those migrating downstream between May and July and lowest for those emigrating in September. Based on the present results, it was hypothesized that S. salar emigrating between April and August migrated directly out into the ocean, while those that emigrated between October and March stayed in the estuary until the subsequent spring. © 2014 The Fisheries Society of the British Isles post-smolts; recapture rate; sea growth; seasonal seaward migration; water temperature. acceptedVersion Article in Journal/Newspaper Atlantic salmon Salmo salar Norwegian Institute for Nature Research: Brage NINA Norway Journal of Fish Biology 84 5 1457 1473 |
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Open Polar |
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Norwegian Institute for Nature Research: Brage NINA |
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language |
English |
description |
Whether time of seaward migration of young Atlantic salmon Salmo salar influences their subsequent survival and growth was investigated in the River Imsa, south-western Norway. Salmo salar were tagged when moving downstream through a trap near the outlet between 1976 and 2010 and recaptured on their adult return.Most descended as smolts in April and May, but some descended during the other months of the year. Annual variation in timing of the smolt migration was significantly correlated with variation in water temperature during spring. Mean total body length of the descending S. salar varied with month of seaward migration. The sea survival of S. salar emigrating from the River Imsa between January and May was 2⋅8 times higher than for those descending between June and December. The sea survival of the various cohorts decreased with increasing river temperature in April to May, prior to the smolt migration, and decreasing day number when the smolts moved to sea. The size of smolts descending the river between April and May did not affect the survival at sea as much as it affected the survival of migrants descending in any other month of the year. The majority of the downstream migrating S. salar were 2 years old, but proportionally, more 1 year olds moved downstream in the autumn than in the rest of the year.Mean duration between downstream migration of the young and the return migration of the grilse was shortest (12⋅7 months) for those descending in July and August and longest for those descending in October (21 months). Mean monthly specific growth rate was highest for those migrating downstream between May and July and lowest for those emigrating in September. Based on the present results, it was hypothesized that S. salar emigrating between April and August migrated directly out into the ocean, while those that emigrated between October and March stayed in the estuary until the subsequent spring. © 2014 The Fisheries Society of the British Isles post-smolts; recapture rate; sea growth; seasonal seaward migration; water temperature. acceptedVersion |
format |
Article in Journal/Newspaper |
author |
Jonsson, Nina Jonsson, Bror |
spellingShingle |
Jonsson, Nina Jonsson, Bror Time and size at seaward migration influence the sea survival of Salmo salar |
author_facet |
Jonsson, Nina Jonsson, Bror |
author_sort |
Jonsson, Nina |
title |
Time and size at seaward migration influence the sea survival of Salmo salar |
title_short |
Time and size at seaward migration influence the sea survival of Salmo salar |
title_full |
Time and size at seaward migration influence the sea survival of Salmo salar |
title_fullStr |
Time and size at seaward migration influence the sea survival of Salmo salar |
title_full_unstemmed |
Time and size at seaward migration influence the sea survival of Salmo salar |
title_sort |
time and size at seaward migration influence the sea survival of salmo salar |
publishDate |
2014 |
url |
http://hdl.handle.net/11250/2478316 https://doi.org/10.1111/jfb.12370 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_source |
1457-1473 84 Journal of Fish Biology 5 |
op_relation |
Andre: Directorate for Nature Management Norges forskningsråd: 225014 Egen institusjon: NINA Journal of Fish Biology. 2014, 84 (5), 1457-1473. urn:issn:0022-1112 http://hdl.handle.net/11250/2478316 https://doi.org/10.1111/jfb.12370 cristin:1133183 |
op_doi |
https://doi.org/10.1111/jfb.12370 |
container_title |
Journal of Fish Biology |
container_volume |
84 |
container_issue |
5 |
container_start_page |
1457 |
op_container_end_page |
1473 |
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1766363507229458432 |