Cette etude decrit les variations saisonnieres, interannuelles et spatiales de la taille et de l'age au debut de la metamorphose chez la sole, Solea solea. La taille au debut de la metamorphose est considerablement moins variable que lage et le poids: CV taille<CV age<CV poids (0.08, 0.2 et 0.25 respectivement). Taille et age au debut de la metamorphose ne sont pas significativement correles (r 2 =0.02). Les larves de sole commencent a se metamorphoser a une faille relativement constante 8.5 +/- 1.3 mm et les comparaisons saisonnieres, interannuelles et spatiales montrent que cette taille n'est pas significativement variable. Contrairement a la taille, les variations saisonnieres et interannuelles de lage au debut de la metamorphose sont elevees Elles dependent des differences du taux de croissance qui lui-meme est correlea l'evolution thermique et a la disponibilite en nourriture. La comparaison de la largeur moyenne des accroissements de la sagitta suggere que les differences entre larves a croissance lente et larves a croissance rapide s'etablissent principalement a partir du 10ieme jour apres le stade de l'ouverture de la bouche et qu'elles ont tendance a s'attenuer a la fin de la periode larvaire. Ces resultats sont discutes en regard de leurs implications sur la survie et le recrutement.
This study describes seasonal, interannual and spatial variations of size and age at the onset of metamorphosis of sole, Solea solea. Length at the onset of metamorphosis was significantly less variable than age and weight: coefficient of variation CV length<CV age<CV weight (0.08, 0.2, 0.25, respectively). Length and age at the onset of metamorphosis were not significantly correlated (r 2 =0.02). Sole larvae began metamorphosis at a relatively constant length 8.5 +/- 1.3 mm and seasonal, interannual and spatial comparisons showed that length was not significantly variable. Unlike length, seasonal and interannual variations of age at the onset of metamorphosis were high, and resulted from differences in growth rates which were influenced by both temperature and food availability. Analysis of otolith increment width suggest that these growth differences between slow-growing and fast-growing larvae occurred chiefly after the 10th day following the mouth-opening stage and seemed to diminish at the end of the larval period. These findings are discussed in terms of survival and recruitment variability.