Population estimates of juvenile Atlantic salmon, Salmo salar, as indices of smolt production in the R. Scorff, Brittany
The numerical production of juvenile Atlantic salmon was estimated on an Armorican Massif river (Brittany), using habitat characteristics of the main stream and an annual electrofishing census from 1975 to 1983. This showed that (i) 0 + fish accounted for 79% of the production; (ii) there were large...
| Published in: | Journal of Fish Biology |
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| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Wiley
1986
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1111/j.1095-8649.1986.tb04962.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1095-8649.1986.tb04962.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1095-8649.1986.tb04962.x |
| Summary: | The numerical production of juvenile Atlantic salmon was estimated on an Armorican Massif river (Brittany), using habitat characteristics of the main stream and an annual electrofishing census from 1975 to 1983. This showed that (i) 0 + fish accounted for 79% of the production; (ii) there were larger annual variations of production in spite of some compensatory events depending on genetic and environmental factors; (iii) riffles and rapids (depth <40cm, current velocity > 40 cm s −1 ) were the more productive habitats, providing 86.4% of the production from 28% of the water area; (iv) the middle course of the river accounted for 57.6% of production, producing more 1 + individuals in a large area of rapids. Features of this method, their limitations and the value of the results are discussed in relation to the estimation of smolt production. |
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