Inshore migration of a tropical eel, Anguilla marmorata, from Taiwanese and Japanese coasts

The otolith microstructure and microchemistry of a tropical eel, Anguilla marmorata, were examined in glass eels collected from Taiwanese and Japanese coasts. Ages at metamorphosis (onset of metamorphosis) and recruitment, respectively, were 114 +- 13.8 (mean +- SD) days and 144 +- 15.7 days in Taiwanese stock, and 123 +- 13.9 days and 154 +- 17.3 days in Japanese stock. No significant differences were found in ages between the two stocks. The duration of metamorphosis estimated from otolith microstructure was 10-24 days, which is the same in the different stocks. For both stocks examined, close linear relationships were found between ages at metamorphosis and recruitment, suggesting that individuals that metamorphosed earlier were recruited to the coasts at a younger age.