Timing of migration and changes in age structure of Atlantic salmon, Salmo salar L., in the River Frome, a Dorset chalk stream, over a 24‐year period
During the last 24 years, the number of Atlantic salmon, Salmo salar L., migrating up the River Frome has varied between < 1000 and > 4000 fish per annum. Most parr become smolts at age 1+ and there are three main sea ages of salmon returning to the river. Each sea age shows a bimodal pattern...
Published in: | Fisheries Management and Ecology |
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Language: | English |
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Online Access: | http://dx.doi.org/10.1046/j.1365-2400.1999.00166.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2400.1999.00166.x https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2400.1999.00166.x |
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crwiley:10.1046/j.1365-2400.1999.00166.x 2024-06-02T08:03:32+00:00 Timing of migration and changes in age structure of Atlantic salmon, Salmo salar L., in the River Frome, a Dorset chalk stream, over a 24‐year period Welton, J. S. Beaumont, W. R. C. Ladle, M. 1999 http://dx.doi.org/10.1046/j.1365-2400.1999.00166.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2400.1999.00166.x https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2400.1999.00166.x en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Fisheries Management and Ecology volume 6, issue 6, page 437-458 ISSN 0969-997X 1365-2400 journal-article 1999 crwiley https://doi.org/10.1046/j.1365-2400.1999.00166.x 2024-05-03T11:19:21Z During the last 24 years, the number of Atlantic salmon, Salmo salar L., migrating up the River Frome has varied between < 1000 and > 4000 fish per annum. Most parr become smolts at age 1+ and there are three main sea ages of salmon returning to the river. Each sea age shows a bimodal pattern of migration in the river. Primary migration times for 3‐sea‐winter (3SW) fish are spring and autumn, with 2SW fish and grilse (1SW) peaking in summer and autumn. Some 28.4% of 3SW and 6.9% of 2SW fish are previous spawners. Multi‐sea‐winter fish historically passed over the counter in all months of the year, but recently, their numbers have declined, as have total numbers of fish of all ages. There has been a fundamental change in the age structure of the population, with grilse increasing in proportion over the study period. Photographs of fish, taken for validation of the counter, showed a significant decrease in mean length of grilse, but an increase in mean length for 2SW and 3SW fish. Rod catch data support these findings. Article in Journal/Newspaper Atlantic salmon Salmo salar Wiley Online Library Fisheries Management and Ecology 6 6 437 458 |
institution |
Open Polar |
collection |
Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
description |
During the last 24 years, the number of Atlantic salmon, Salmo salar L., migrating up the River Frome has varied between < 1000 and > 4000 fish per annum. Most parr become smolts at age 1+ and there are three main sea ages of salmon returning to the river. Each sea age shows a bimodal pattern of migration in the river. Primary migration times for 3‐sea‐winter (3SW) fish are spring and autumn, with 2SW fish and grilse (1SW) peaking in summer and autumn. Some 28.4% of 3SW and 6.9% of 2SW fish are previous spawners. Multi‐sea‐winter fish historically passed over the counter in all months of the year, but recently, their numbers have declined, as have total numbers of fish of all ages. There has been a fundamental change in the age structure of the population, with grilse increasing in proportion over the study period. Photographs of fish, taken for validation of the counter, showed a significant decrease in mean length of grilse, but an increase in mean length for 2SW and 3SW fish. Rod catch data support these findings. |
format |
Article in Journal/Newspaper |
author |
Welton, J. S. Beaumont, W. R. C. Ladle, M. |
spellingShingle |
Welton, J. S. Beaumont, W. R. C. Ladle, M. Timing of migration and changes in age structure of Atlantic salmon, Salmo salar L., in the River Frome, a Dorset chalk stream, over a 24‐year period |
author_facet |
Welton, J. S. Beaumont, W. R. C. Ladle, M. |
author_sort |
Welton, J. S. |
title |
Timing of migration and changes in age structure of Atlantic salmon, Salmo salar L., in the River Frome, a Dorset chalk stream, over a 24‐year period |
title_short |
Timing of migration and changes in age structure of Atlantic salmon, Salmo salar L., in the River Frome, a Dorset chalk stream, over a 24‐year period |
title_full |
Timing of migration and changes in age structure of Atlantic salmon, Salmo salar L., in the River Frome, a Dorset chalk stream, over a 24‐year period |
title_fullStr |
Timing of migration and changes in age structure of Atlantic salmon, Salmo salar L., in the River Frome, a Dorset chalk stream, over a 24‐year period |
title_full_unstemmed |
Timing of migration and changes in age structure of Atlantic salmon, Salmo salar L., in the River Frome, a Dorset chalk stream, over a 24‐year period |
title_sort |
timing of migration and changes in age structure of atlantic salmon, salmo salar l., in the river frome, a dorset chalk stream, over a 24‐year period |
publisher |
Wiley |
publishDate |
1999 |
url |
http://dx.doi.org/10.1046/j.1365-2400.1999.00166.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2400.1999.00166.x https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2400.1999.00166.x |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_source |
Fisheries Management and Ecology volume 6, issue 6, page 437-458 ISSN 0969-997X 1365-2400 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1046/j.1365-2400.1999.00166.x |
container_title |
Fisheries Management and Ecology |
container_volume |
6 |
container_issue |
6 |
container_start_page |
437 |
op_container_end_page |
458 |
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1800748095189811200 |