Growth potential can affect timing of maturity in a long-lived semelparous fish

• Published in: Biology Letters
• Main Authors: Yokouchi, K., Daverat, F., Fukuda, N., Sudo, R., Miller, M. J., Tsukamoto, K., Elie, P., Poole, R.
• Other Authors: NATIONAL RESEARCH INSTITUTE OF FISHERIES SCIENCE YOKOSUKA JAP, IRSTEA BORDEAUX UR EABX FRA, NATIONAL RESEARCH INSTITUTE OF AQUACULTURE MINAMI ISE JAP, NIHON UNIVERSITY FUJISAWA JAP, MARINE INSTITUTE NEWPORT IRL
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2018
• Subjects: ANGUILLA ANGUILLA; OTOLITHE; MATURATION; DYNAMIQUE DE POPULATION; statoliths; population dynamics; Anguilla anguilla; European eel
• Online Access: https://irsteadoc.irstea.fr/cemoa/PUB00059706

Many diadromous fishes such as salmon and eels that move between freshwater and the ocean have evolved semelparous reproductive strategies, but both groups display considerable plasticity in characteristics. Factors such as population density and growth, predation risk or reproduction cost have been found to influence timing of maturation. We investigated the relationship between female size at maturity and individual growth trajectories of the long-lived semelparous European eel, Anguilla anguilla. A Bayesian model was applied to 338 individual growth trajectories of maturing migration-stage female silver eels from France, Ireland, the Netherlands and Hungary. The results clearly showed that when growth rates declined, the onset of maturation was triggered, and the eels left their growth habitats and migrated to the spawning area. Therefore, female eels tended to attain larger body size when the growth conditions were good enough to risk spending extra time in their growth habitats. This flexible maturation strategy is likely related to the ability to use diverse habitats with widely ranging growth and survival potentials in the catadromous life-history across its wide species range