Early life history and recruitment dynamics of amphidromous goby Sicyopterus japonicus

• Main Authors: SHEN, KANG-NING, 沈康寧
• Other Authors: WANN-NIAN TZENG, YING-CHOU LEE
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/62622214731999357534

碩士 === 國立臺灣大學 === 漁業科學研究所 === 85 === Sicyopterus japonicus, a common species of amphidromous Gobiidae fish, widespread in the stream of eastern Taiwan. In this study we used theinformation achieved from otolith microstructure and microchemistry ( Sr:Ca ) of the fish collected in the Long-Long brook and its estuaryfrom September 1995 through April 1997 as well as environment factors to investigate the early life history and recruitment dynamics. Changes in otolithChanges in otolith microchemistry and microstructure suggest that metamorphosis check is deposited at the time approximately two weeks after migration from sea water into freshwater. The growth of otolith dramatically increasesafter metamorphosis. The change of jaw structure of the fish may contribute to the dramatic growth. The total lengths of Sicyopterus japonicus juvenilesat recruitment to the Shung-Chi River estuary were 33.95mm in average (range 30-38mm, n=384) and daily age were 163.72 days in average(range 125-212days,n=277). The timing of recruitment of the juvenile fish and their spawningseason back-calculated from sampling date are correlated with precipitationand water temperature. Both length and age of the juvenile at recruitment tothe estuary show a periodic change and the peak phase of change is reversebetween length and age. The periodic change in both length and age depends onthe seasonal change of productivity during their postlarval stage in the ocean.