Feeding, growth and nutritional status of restocked salmon parr along the longitudinal gradient of a large European river: the Allier

Aurélie Descroix (1) , Christian Desvilettes (1) , P. Martin (2) , O. Anneville (3) , Alexandre Bec (1) , Gilles Bourdier (1)

1 LMGE - Laboratoire Microorganismes : Génome et Environnement
2 Conservatoire National du Saumon Sauvage
3 CARRTEL - Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques

The feeding, growth and nutritional status of salmon parr (0+) released at fry stage in different riffles were studied in a large temperate river (Allier, France) throughout the active feeding period. Significant differences were observed along the upstream–downstream gradient. Parr growth performance and energy storage were higher in downstream riffles and low in the most upstream one. These longitudinal growth variations are discussed in the context of diet and food availability differences, habitat variables and intra- and inter-species competition. The most favourable site for optimum growth and nutritional status appeared to be the intermediary riffle located in the grayling zone.

Mots clés: feeding and growth; nutritional status; upstream–downstream gradient; large temperate river; Salmo salar L

Domaines: Sciences de l'environnement

Aurélie Descroix, Christian Desvilettes, P. Martin, O. Anneville, Alexandre Bec, et al.. Feeding, growth and nutritional status of restocked salmon parr along the longitudinal gradient of a large European river: the Allier. Ecology of Fresh Water Fish, 2009, 18 (2), pp.282-296. ⟨10.1111/j.1600-0633.2008.00345.x⟩. ⟨hal-00525872⟩