|
|
Acolas, M; Veron, V; Jourdan, H; Begout, Marie-laure; Sabatie, M; Bagliniere, J.l.. |
The characteristics and activity of adult allis shad [Alosa alosa (L.)] were analysed during the last part of their upstream migration in the L'Aulne, a small river in Brittany, and during reproduction on a unique spawning ground downstream of an insurmountable dam. The age of the spawners ranged front three to seven years, females being larger and older than males. Population-level migration and reproduction were studied by counting the number of migrating fish, by estimating the sex ratio, and by counting the number of nocturnal spawning acts for three consecutive years starting in 2000. The influence of the environment, especially water temperature and discharge, was highlighted: temperature during migration may supplant the influence of water flow,... |
Tipo: Text |
Palavras-chave: Small river; Reproduction; Biological features; Anadromous migration; Allis shad. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1214.pdf |
| |