Abundance, seasonality and size of Atlantic salmon smolts entrained on power station intake screens in the Severn Estuary
Atlantic salmon smolts were sampled from the intake screens of the Oldbury power station in the inner Severn Estuary at weekly intervals between July 1972 and June 1977. These catches, and those taken over nearly three years from the nearby Berkeley power station, demonstrated that the abundance of...
Published in: | Journal of the Marine Biological Association of the United Kingdom |
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Language: | English |
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Cambridge University Press (CUP)
1994
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Online Access: | http://dx.doi.org/10.1017/s0025315400047640 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0025315400047640 |
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crcambridgeupr:10.1017/s0025315400047640 2024-03-03T08:42:49+00:00 Abundance, seasonality and size of Atlantic salmon smolts entrained on power station intake screens in the Severn Estuary Claridge, P.N. Potter, I.C. 1994 http://dx.doi.org/10.1017/s0025315400047640 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0025315400047640 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Journal of the Marine Biological Association of the United Kingdom volume 74, issue 3, page 527-534 ISSN 0025-3154 1469-7769 Aquatic Science journal-article 1994 crcambridgeupr https://doi.org/10.1017/s0025315400047640 2024-02-08T08:24:49Z Atlantic salmon smolts were sampled from the intake screens of the Oldbury power station in the inner Severn Estuary at weekly intervals between July 1972 and June 1977. These catches, and those taken over nearly three years from the nearby Berkeley power station, demonstrated that the abundance of smolts in the estuary peaked in autumn (October) and, to a far greater extent, in spring (April and May). However, small numbers of smolts were occasionally found in all other months of the year except July. Standard length-frequency distributions of smolts remained unimodal throughout the year. Lengths ranged from 76 to 187 mm, mean 130·2 ±1·87 mm (95% CL), and wet weights ranged from 5·4 to 68·0 g, mean 26·9 ±1·17 g. The mean monthly standard length of smolts increased slightly between the autumn of one year and the spring/early summer of the next year, suggesting that, on average, the former were six months younger than the latter. The condition factor was significantly greater in autumn (1·40) than in spring (1·23). It is estimated that the total number of salmon smolts entrained annually on the screens at Oldbury during the five years ranged from 92 to 791, with a mean of 405. Total estimated numbers at Berkeley ranged from 196 to 788 per annum. The numbers at Oldbury are lower than those estimated for the downstream migrants of the Twaite shad, another anadromous species, and far lower than those of the most abundant of the marine fish species that use the Severn Estuary as a nursery area. Article in Journal/Newspaper Atlantic salmon Cambridge University Press Journal of the Marine Biological Association of the United Kingdom 74 3 527 534 |
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Cambridge University Press |
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language |
English |
topic |
Aquatic Science |
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Aquatic Science Claridge, P.N. Potter, I.C. Abundance, seasonality and size of Atlantic salmon smolts entrained on power station intake screens in the Severn Estuary |
topic_facet |
Aquatic Science |
description |
Atlantic salmon smolts were sampled from the intake screens of the Oldbury power station in the inner Severn Estuary at weekly intervals between July 1972 and June 1977. These catches, and those taken over nearly three years from the nearby Berkeley power station, demonstrated that the abundance of smolts in the estuary peaked in autumn (October) and, to a far greater extent, in spring (April and May). However, small numbers of smolts were occasionally found in all other months of the year except July. Standard length-frequency distributions of smolts remained unimodal throughout the year. Lengths ranged from 76 to 187 mm, mean 130·2 ±1·87 mm (95% CL), and wet weights ranged from 5·4 to 68·0 g, mean 26·9 ±1·17 g. The mean monthly standard length of smolts increased slightly between the autumn of one year and the spring/early summer of the next year, suggesting that, on average, the former were six months younger than the latter. The condition factor was significantly greater in autumn (1·40) than in spring (1·23). It is estimated that the total number of salmon smolts entrained annually on the screens at Oldbury during the five years ranged from 92 to 791, with a mean of 405. Total estimated numbers at Berkeley ranged from 196 to 788 per annum. The numbers at Oldbury are lower than those estimated for the downstream migrants of the Twaite shad, another anadromous species, and far lower than those of the most abundant of the marine fish species that use the Severn Estuary as a nursery area. |
format |
Article in Journal/Newspaper |
author |
Claridge, P.N. Potter, I.C. |
author_facet |
Claridge, P.N. Potter, I.C. |
author_sort |
Claridge, P.N. |
title |
Abundance, seasonality and size of Atlantic salmon smolts entrained on power station intake screens in the Severn Estuary |
title_short |
Abundance, seasonality and size of Atlantic salmon smolts entrained on power station intake screens in the Severn Estuary |
title_full |
Abundance, seasonality and size of Atlantic salmon smolts entrained on power station intake screens in the Severn Estuary |
title_fullStr |
Abundance, seasonality and size of Atlantic salmon smolts entrained on power station intake screens in the Severn Estuary |
title_full_unstemmed |
Abundance, seasonality and size of Atlantic salmon smolts entrained on power station intake screens in the Severn Estuary |
title_sort |
abundance, seasonality and size of atlantic salmon smolts entrained on power station intake screens in the severn estuary |
publisher |
Cambridge University Press (CUP) |
publishDate |
1994 |
url |
http://dx.doi.org/10.1017/s0025315400047640 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0025315400047640 |
genre |
Atlantic salmon |
genre_facet |
Atlantic salmon |
op_source |
Journal of the Marine Biological Association of the United Kingdom volume 74, issue 3, page 527-534 ISSN 0025-3154 1469-7769 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0025315400047640 |
container_title |
Journal of the Marine Biological Association of the United Kingdom |
container_volume |
74 |
container_issue |
3 |
container_start_page |
527 |
op_container_end_page |
534 |
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1792498278461341696 |