| Titre : | Variation of life traits of glass eels of Anguilla anguilla (L.) during the colonization of Rios Naln and Minho estuaries (northwestern Iberian Peninsula) |
| Auteurs : | Tania Iglesias, Auteur ; Javier Lobon-Cervia, Auteur ; Sergia Costa Dias, Auteur ; Carlos Antunes, Auteur |
| Type de document : | Article |
| Dans : | Hydrobiologia (651(1) SEP 2010) |
| Article en page(s) : | 213-223 |
| Résumé : | Analyses of the pigmentation stages and the size of glass eels during the arrival period to two northwestern Iberian estuaries (Rios Naln and Minho) and comparison of the patterns elucidated in this study with those reported for other geographical locations of the Atlantic and Mediterranean ranges showed nine pigmentation stages ranging from practically transparent to fully pigmented in the two-first locations. Overall, stage V-B was predominant but within a broad variance across rivers and seasons. Consistent with previous studies, pigmentation stages tended to increase when the season progressed whilst, for a given individual length, mass tended to be higher during the early months of arrival. Moreover, both mass and condition factor were lower in individuals of advanced stages. Whilst we found no significant differences on glass eels length among pigmentation stages, both mass and condition factor were lower in more pigmented individuals. Given that larger glass eels with better physical condition may reveal greater energy content implying improved upstream migration earlier individuals may be better migrants than latter individuals. |



